CN116676630A - Phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, preparation method and application thereof - Google Patents
Phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, preparation method and application thereof Download PDFInfo
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 101
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 99
- 239000002131 composite material Substances 0.000 title claims abstract description 89
- 239000002105 nanoparticle Substances 0.000 title claims abstract description 76
- 238000002360 preparation method Methods 0.000 title claims abstract description 23
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 69
- 239000001257 hydrogen Substances 0.000 claims abstract description 69
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 69
- 238000006243 chemical reaction Methods 0.000 claims abstract description 32
- 238000010438 heat treatment Methods 0.000 claims abstract description 29
- 239000002243 precursor Substances 0.000 claims abstract description 26
- 238000000197 pyrolysis Methods 0.000 claims abstract description 24
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 22
- 238000000034 method Methods 0.000 claims abstract description 21
- -1 ammonium ions Chemical class 0.000 claims abstract description 16
- 239000004094 surface-active agent Substances 0.000 claims abstract description 15
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 14
- 239000011574 phosphorus Substances 0.000 claims abstract description 14
- 229910052751 metal Inorganic materials 0.000 claims abstract description 13
- 239000002184 metal Substances 0.000 claims abstract description 13
- 238000004108 freeze drying Methods 0.000 claims abstract description 12
- 229910044991 metal oxide Inorganic materials 0.000 claims abstract description 12
- 150000004706 metal oxides Chemical class 0.000 claims abstract description 12
- 239000011259 mixed solution Substances 0.000 claims abstract description 7
- 238000002156 mixing Methods 0.000 claims abstract description 7
- 239000003054 catalyst Substances 0.000 claims description 49
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 41
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical group [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 claims description 31
- 229910052757 nitrogen Inorganic materials 0.000 claims description 19
- AMWVZPDSWLOFKA-UHFFFAOYSA-N phosphanylidynemolybdenum Chemical compound [Mo]#P AMWVZPDSWLOFKA-UHFFFAOYSA-N 0.000 claims description 19
- 229910052750 molybdenum Inorganic materials 0.000 claims description 17
- WHNWPMSKXPGLAX-UHFFFAOYSA-N N-Vinyl-2-pyrrolidone Chemical group C=CN1CCCC1=O WHNWPMSKXPGLAX-UHFFFAOYSA-N 0.000 claims description 14
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 13
- 239000011733 molybdenum Substances 0.000 claims description 13
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 13
- 229910052721 tungsten Inorganic materials 0.000 claims description 13
- 239000011780 sodium chloride Substances 0.000 claims description 12
- CBOJBBMQJBVCMW-BTVCFUMJSA-N (2r,3r,4s,5r)-2-amino-3,4,5,6-tetrahydroxyhexanal;hydrochloride Chemical compound Cl.O=C[C@H](N)[C@@H](O)[C@H](O)[C@H](O)CO CBOJBBMQJBVCMW-BTVCFUMJSA-N 0.000 claims description 11
- MSWZFWKMSRAUBD-UHFFFAOYSA-N beta-D-galactosamine Natural products NC1C(O)OC(CO)C(O)C1O MSWZFWKMSRAUBD-UHFFFAOYSA-N 0.000 claims description 11
- 229960001911 glucosamine hydrochloride Drugs 0.000 claims description 11
- 239000010937 tungsten Substances 0.000 claims description 10
- 229920003081 Povidone K 30 Polymers 0.000 claims description 9
- KWSLGOVYXMQPPX-UHFFFAOYSA-N 5-[3-(trifluoromethyl)phenyl]-2h-tetrazole Chemical group FC(F)(F)C1=CC=CC(C2=NNN=N2)=C1 KWSLGOVYXMQPPX-UHFFFAOYSA-N 0.000 claims description 7
- 229910001379 sodium hypophosphite Inorganic materials 0.000 claims description 7
- QWMFKVNJIYNWII-UHFFFAOYSA-N 5-bromo-2-(2,5-dimethylpyrrol-1-yl)pyridine Chemical compound CC1=CC=C(C)N1C1=CC=C(Br)C=N1 QWMFKVNJIYNWII-UHFFFAOYSA-N 0.000 claims description 6
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 claims description 6
- 239000012298 atmosphere Substances 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- UYDPQDSKEDUNKV-UHFFFAOYSA-N phosphanylidynetungsten Chemical compound [W]#P UYDPQDSKEDUNKV-UHFFFAOYSA-N 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 4
- MEFBJEMVZONFCJ-UHFFFAOYSA-N molybdate Chemical compound [O-][Mo]([O-])(=O)=O MEFBJEMVZONFCJ-UHFFFAOYSA-N 0.000 claims description 4
- LDDMACCNBZAMSG-BDVNFPICSA-N (2r,3r,4s,5r)-3,4,5,6-tetrahydroxy-2-(methylamino)hexanal Chemical compound CN[C@@H](C=O)[C@@H](O)[C@H](O)[C@H](O)CO LDDMACCNBZAMSG-BDVNFPICSA-N 0.000 claims description 3
- MSWZFWKMSRAUBD-GASJEMHNSA-N 2-amino-2-deoxy-D-galactopyranose Chemical compound N[C@H]1C(O)O[C@H](CO)[C@H](O)[C@@H]1O MSWZFWKMSRAUBD-GASJEMHNSA-N 0.000 claims description 3
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 3
- 229910052700 potassium Inorganic materials 0.000 claims description 3
- 239000011591 potassium Substances 0.000 claims description 3
- 239000001103 potassium chloride Substances 0.000 claims description 3
- 235000011164 potassium chloride Nutrition 0.000 claims description 3
- 235000015393 sodium molybdate Nutrition 0.000 claims description 3
- 239000011684 sodium molybdate Substances 0.000 claims description 3
- TVXXNOYZHKPKGW-UHFFFAOYSA-N sodium molybdate (anhydrous) Chemical compound [Na+].[Na+].[O-][Mo]([O-])(=O)=O TVXXNOYZHKPKGW-UHFFFAOYSA-N 0.000 claims description 3
- OVRNDRQMDRJTHS-UHFFFAOYSA-N N-acelyl-D-glucosamine Natural products CC(=O)NC1C(O)OC(CO)C(O)C1O OVRNDRQMDRJTHS-UHFFFAOYSA-N 0.000 claims description 2
- OVRNDRQMDRJTHS-FMDGEEDCSA-N N-acetyl-beta-D-glucosamine Chemical compound CC(=O)N[C@H]1[C@H](O)O[C@H](CO)[C@@H](O)[C@@H]1O OVRNDRQMDRJTHS-FMDGEEDCSA-N 0.000 claims description 2
- MBLBDJOUHNCFQT-LXGUWJNJSA-N N-acetylglucosamine Natural products CC(=O)N[C@@H](C=O)[C@@H](O)[C@H](O)[C@H](O)CO MBLBDJOUHNCFQT-LXGUWJNJSA-N 0.000 claims description 2
- AAQNGTNRWPXMPB-UHFFFAOYSA-N dipotassium;dioxido(dioxo)tungsten Chemical compound [K+].[K+].[O-][W]([O-])(=O)=O AAQNGTNRWPXMPB-UHFFFAOYSA-N 0.000 claims description 2
- 229950006780 n-acetylglucosamine Drugs 0.000 claims description 2
- 230000001681 protective effect Effects 0.000 claims description 2
- 239000010411 electrocatalyst Substances 0.000 abstract description 36
- 230000000694 effects Effects 0.000 abstract description 18
- 230000008569 process Effects 0.000 abstract description 10
- 239000000463 material Substances 0.000 description 19
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 18
- 230000005540 biological transmission Effects 0.000 description 16
- 239000003575 carbonaceous material Substances 0.000 description 16
- 238000002441 X-ray diffraction Methods 0.000 description 15
- 230000002776 aggregation Effects 0.000 description 13
- 238000005054 agglomeration Methods 0.000 description 12
- 238000001228 spectrum Methods 0.000 description 12
- 102000020897 Formins Human genes 0.000 description 10
- 108091022623 Formins Proteins 0.000 description 10
- XYFCBTPGUUZFHI-UHFFFAOYSA-N Phosphine Chemical compound P XYFCBTPGUUZFHI-UHFFFAOYSA-N 0.000 description 10
- QXYJCZRRLLQGCR-UHFFFAOYSA-N dioxomolybdenum Chemical compound O=[Mo]=O QXYJCZRRLLQGCR-UHFFFAOYSA-N 0.000 description 10
- 238000005868 electrolysis reaction Methods 0.000 description 10
- 239000007788 liquid Substances 0.000 description 10
- DZKDPOPGYFUOGI-UHFFFAOYSA-N tungsten(iv) oxide Chemical compound O=[W]=O DZKDPOPGYFUOGI-UHFFFAOYSA-N 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- 239000003792 electrolyte Substances 0.000 description 9
- 230000010287 polarization Effects 0.000 description 9
- 229920000036 polyvinylpyrrolidone Polymers 0.000 description 9
- 235000013855 polyvinylpyrrolidone Nutrition 0.000 description 9
- MSWZFWKMSRAUBD-IVMDWMLBSA-N 2-amino-2-deoxy-D-glucopyranose Chemical compound N[C@H]1C(O)O[C@H](CO)[C@@H](O)[C@@H]1O MSWZFWKMSRAUBD-IVMDWMLBSA-N 0.000 description 8
- FZHXIRIBWMQPQF-UHFFFAOYSA-N Glc-NH2 Natural products O=CC(N)C(O)C(O)C(O)CO FZHXIRIBWMQPQF-UHFFFAOYSA-N 0.000 description 8
- 238000001816 cooling Methods 0.000 description 8
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 8
- 238000004321 preservation Methods 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- AFCARXCZXQIEQB-UHFFFAOYSA-N N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CCNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 AFCARXCZXQIEQB-UHFFFAOYSA-N 0.000 description 6
- 239000008367 deionised water Substances 0.000 description 6
- 229910021641 deionized water Inorganic materials 0.000 description 6
- 238000011065 in-situ storage Methods 0.000 description 6
- 230000014759 maintenance of location Effects 0.000 description 6
- 230000003197 catalytic effect Effects 0.000 description 5
- 239000013078 crystal Substances 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 229910000073 phosphorus hydride Inorganic materials 0.000 description 5
- 230000002829 reductive effect Effects 0.000 description 5
- 230000000630 rising effect Effects 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- 238000000026 X-ray photoelectron spectrum Methods 0.000 description 3
- 229910001873 dinitrogen Inorganic materials 0.000 description 3
- 238000005087 graphitization Methods 0.000 description 3
- 238000000227 grinding Methods 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- MGRWKWACZDFZJT-UHFFFAOYSA-N molybdenum tungsten Chemical compound [Mo].[W] MGRWKWACZDFZJT-UHFFFAOYSA-N 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 230000009257 reactivity Effects 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- 150000001721 carbon Chemical class 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000002425 crystallisation Methods 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 238000002484 cyclic voltammetry Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000001747 exhibiting effect Effects 0.000 description 2
- 230000000977 initiatory effect Effects 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 229910000510 noble metal Inorganic materials 0.000 description 2
- 238000000643 oven drying Methods 0.000 description 2
- 230000036961 partial effect Effects 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 239000001267 polyvinylpyrrolidone Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 230000002194 synthesizing effect Effects 0.000 description 2
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- DSVGQVZAZSZEEX-UHFFFAOYSA-N [C].[Pt] Chemical compound [C].[Pt] DSVGQVZAZSZEEX-UHFFFAOYSA-N 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- AAMATCKFMHVIDO-UHFFFAOYSA-N azane;1h-pyrrole Chemical compound N.C=1C=CNC=1 AAMATCKFMHVIDO-UHFFFAOYSA-N 0.000 description 1
- DLGYNVMUCSTYDQ-UHFFFAOYSA-N azane;pyridine Chemical compound N.C1=CC=NC=C1 DLGYNVMUCSTYDQ-UHFFFAOYSA-N 0.000 description 1
- 239000013590 bulk material Substances 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000003795 desorption Methods 0.000 description 1
- ZOMNIUBKTOKEHS-UHFFFAOYSA-L dimercury dichloride Chemical class Cl[Hg][Hg]Cl ZOMNIUBKTOKEHS-UHFFFAOYSA-L 0.000 description 1
- 238000003411 electrode reaction Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 229910021397 glassy carbon Inorganic materials 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 238000007709 nanocrystallization Methods 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 125000004437 phosphorous atom Chemical group 0.000 description 1
- 229910052573 porcelain Inorganic materials 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- PBYZMCDFOULPGH-UHFFFAOYSA-N tungstate Chemical compound [O-][W]([O-])(=O)=O PBYZMCDFOULPGH-UHFFFAOYSA-N 0.000 description 1
- 238000001132 ultrasonic dispersion Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
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- Catalysts (AREA)
Abstract
The application provides a preparation method of a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, which comprises the following steps: a) Mixing a template agent, a surfactant, a carbon source capable of ionizing ammonium ions and a metal source, and freeze-drying the obtained mixed solution to obtain a precursor; b) Carrying out pyrolysis treatment on the precursor to obtain a nitrogen-doped three-dimensional carbon network composite material loaded with metal oxide nano particles; c) And carrying out heat treatment on the nitrogen-doped three-dimensional carbon network composite material and a phosphorus source to obtain the nitrogen-doped three-dimensional carbon network composite material loaded with phosphide nano particles. The application also provides a composite material and application. The preparation method of the composite material provided by the application has stable, safe and controllable process, does not need harsh reaction conditions such as high pressure, vacuum and the like, can be used for preparing hydrogen evolution electrocatalyst in a large scale, and particularly has higher activity and stability when being used as the hydrogen evolution electrocatalyst.
Description
Technical Field
The application relates to the technical field of novel energy material synthesis agent electrocatalyst, in particular to a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, a preparation method and application thereof.
Background
Compared with the traditional thermochemical hydrogen production, the water electrolysis hydrogen production technology is more direct, efficient and environment-friendly, and in the large background of the current energy conversion, the technology is also getting more attention and importance. For the cathode end of the electrolytic water reaction, the electrocatalytic Hydrogen Evolution Reaction (HER) is a direct hydrogen related reduction half reaction, and if the energy consumption of the whole total electrolysis reaction is to be reduced, the choice of an electrocatalyst capable of significantly reducing the reaction overpotential is a key factor. At present, noble metal-based materials (such as 20wt percent Pt/C) show excellent electrocatalytic hydrogen evolution activity, but the defects of extremely low crust abundance, overhigh cost and the like limit the large-scale application of the noble metal-based materials. Therefore, it is important to develop electrocatalysts with abundant resources, low cost, stable properties and high activity.
In recent years, moS 2 、Mo x C、Mo x N、MoP x Molybdenum-based hydrogen evolution catalysts are favored by researchers. Wherein molybdenum phosphide (MoP x ) Can exhibit a higher degree of performance than others in industrial applicationsMolybdenum-based compound (MoS) 2 With M% C x ) Better hydrodesulfurization activity, so that MoP can be inferred x Has stronger action on hydrogen atoms and is also more advantageous in the application of electrocatalytic hydrogen evolution. The first principle calculation shows that the P atoms on the surface of MoP can induce a small amount of negative charge to capture protons and can be hydrogen molecules (H 2 ) Provides higher activity for formation and desorption, avoids H in the system 2 Too high coverage results in reduced catalyst activity. Therefore, from theoretical analysis, moP can reach the level of an excellent hydrogen evolution electrocatalyst, and related researches prove that molybdenum phosphide MoP and WP with similar properties have excellent electrocatalytic hydrogen evolution performance.
In order to further improve the electrochemical performance, nanocrystallization of phosphide (MoP, WP) and introduction of carbon-based materials are all indispensable, so that the overall conductivity of the material can be improved, and the electrode reaction kinetics can be accelerated. The conventional preparation method of the MoP and carbon-based material composite hydrogen evolution electrocatalyst mainly comprises the steps of directly mixing and homogenizing a molybdenum (tungsten) source, a phosphorus source and a carbon source through a solid phase, and then sintering the mixture in one step to obtain a composite material. Although the preparation process is simple, the uneven mixing can cause the active components (MoP and WP) to agglomerate and not be completely coated by the carbon material, thereby reducing the electrocatalytic hydrogen evolution activity. Therefore, the universal preparation method of the phosphide/carbon-based material composite hydrogen evolution electrocatalyst with regular morphology, uniform compounding and excellent activity and industrial application prospect is developed, and has important practical significance for numerous clean energy conversion and storage equipment such as water electrolysis hydrogen production and the like.
Disclosure of Invention
The application solves the technical problem of providing a preparation method of a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, the prepared composite material overcomes the problems of active substance agglomeration and disordered morphology, and the prepared composite material has excellent electrocatalytic hydrogen evolution performance as an electrocatalytic hydrogen evolution catalyst.
In view of the above, the application provides a method for preparing a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, which comprises the following steps:
a) Mixing a template agent, a surfactant, a carbon source capable of ionizing ammonium ions and a metal source, and freeze-drying the obtained mixed solution to obtain a precursor; the metal source is selected from a tungsten source or a molybdenum source;
b) Carrying out pyrolysis treatment on the precursor to obtain a nitrogen-doped three-dimensional carbon network composite material loaded with metal oxide nano particles;
c) And carrying out heat treatment on the nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nano particles and a phosphorus source to obtain the nitrogen-doped three-dimensional carbon network composite material loaded with the phosphide nano particles.
Preferably, the template agent is selected from sodium chloride or potassium chloride, the surfactant is selected from PVP-K30, the molybdenum source is selected from one or more of ammonium heptamolybdate tetrahydrate, sodium molybdate and potassium molybdate, the tungsten source is selected from one or more of potassium tungstate, ammonium tungstate and sodium tungstate dihydrate, the carbon source is selected from one or more of glucosamine hydrochloride, N-methyl-D-glucosamine, D-galactosamine and N-acetamido glucose, and the phosphorus source is selected from anhydrous sodium hypophosphite.
Preferably, the mass ratio of the carbon source to the metal source is 1: (0.5-2), wherein the mass ratio of the template agent, the surfactant and the carbon source is 10: (0.1-0.5): (0.5-2); the mass ratio of the nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nano particles to the phosphorus source is 0.05: (10-20).
Preferably, in step B), the pyrolysis treatment is performed under a protective atmosphere, which is high purity nitrogen.
Preferably, in the step B), the pyrolysis treatment is carried out at a temperature of 500-1000 ℃ for 4-10 hours.
Preferably, in the step C), the heating rate of the heat treatment is 2-10 ℃/min, the temperature is 600-1000 ℃ and the time is 1-5 h.
The application also provides a nitrogen-doped three-dimensional carbon network composite material loaded with phosphide nano particles, which is prepared by the preparation method and comprises a nitrogen-doped three-dimensional carbon network and phosphide nano particles loaded on the surface of the nitrogen-doped three-dimensional carbon network, wherein the phosphide nano particles are selected from molybdenum phosphide or tungsten phosphide.
Preferably, the particle size of the phosphide nano particles is 10-100 nm.
Preferably, the mass percentages of the elements in the composite material are as follows: 25-40% of C, 1-5% of N, 5-10% of O, 30-50% of Mo or W and 10-20% of P.
The application also provides an application of the phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material prepared by the preparation method or used as a catalyst in electrocatalytic hydrogen evolution reaction.
The application provides a preparation method of a nitrogen-doped three-dimensional carbon network composite material loaded with phosphide nanoparticles, which adopts a template agent and is assisted by heat treatment through freeze drying, so that the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum dioxide or tungsten dioxide nanoparticles is prepared, and can be converted into the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum (tungsten) nanoparticles in situ through phosphating treatment, so that the three-dimensional porous morphology of the composite material is well reserved, the problem of material catalytic activity reduction caused by material agglomeration in the process of synthesizing hydrogen evolution electrocatalyst is solved, and phosphide is loaded on a nitrogen-doped three-dimensional carbon network skeleton in situ, therefore, the phosphide nanoparticles are not easy to fall off in the process of participating in electrocatalytic hydrogen evolution reaction, and the long-acting stability of the composite material as a catalyst is ensured.
Experimental results show that the characteristic overpotential of the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum phosphide nano particles, which is prepared by the application, used as a catalyst for electrocatalytic hydrogen evolution reaction is 130mV, is 61mV lower than that of a bulk molybdenum phosphide bulk hydrogen evolution electrocatalyst, and shows excellent electrocatalytic hydrogen evolution activity; the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum phosphide nano particles has excellent long-acting stability as an electrocatalyst, and after a hydrogen evolution reaction electrocatalyst test which lasts for 3000 cycles, the overpotential is only increased by 6mV; after constant potential electrolysis for 20 hours, the output current density retention rate of the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum phosphide nano particles is up to 88%, so that the electrochemical stability of the molybdenum phosphide hydrogen evolution electrocatalyst is improved; the nitrogen-doped three-dimensional carbon network composite material loaded with the tungsten phosphide nano particles is used as the characteristic overpotential 217mV of the electrocatalyst, and after 10h of constant potential electrolysis, the output current density retention rate of the nitrogen-doped three-dimensional carbon network hydrogen evolution electrocatalyst loaded with the molybdenum phosphide nano particles is 75%, and the nitrogen-doped three-dimensional carbon network hydrogen evolution electrocatalyst shows excellent electrocatalytic hydrogen evolution activity and long-acting stability.
Drawings
FIG. 1 shows MoO obtained in example 1 2 X-ray diffraction (XRD) pattern of/NC;
FIG. 2 shows MoO obtained in example 1 2 Scanning Electron Microscope (SEM) photographs (a) and Transmission Electron Microscope (TEM) photographs (b), (c) and High Resolution Transmission Electron Microscope (HRTEM) photographs (d) of the NC composite material;
FIG. 3 is an X-ray diffraction (XRD) spectrum of a sample of the Mo-P/NC-600, moP/NC, mo-P/NC-800 catalyst prepared in examples 2 to 4;
FIG. 4 is a Scanning Electron Microscope (SEM) photograph of the Mo-P/NC-600 and Mo-P/NC-800 catalyst samples prepared in examples 2 and 4;
FIG. 5 is an X-ray diffraction (XRD) spectrum of a MoP/NC catalyst sample prepared in examples 2 and 4;
FIG. 6 is a Scanning Electron Microscope (SEM) photograph (a) and a Transmission Electron Microscope (TEM) photograph (b), (c) and a High Resolution Transmission Electron Microscope (HRTEM) photograph (d) of the MoP/NC catalyst sample prepared in example 3;
FIG. 7 is an X-ray photoelectron spectrum (XPS) of the N element in the MoP/NC catalyst sample prepared in example 3;
FIG. 8 is an X-ray diffraction (XRD) spectrum of MoP bulk and NC catalyst samples prepared in examples 5 to 6;
FIG. 9 is a Scanning Electron Microscope (SEM) photograph of MoP bulk and NC catalyst samples prepared in examples 5-6;
FIG. 10 is a diagram of WO prepared in example 7 2 X-ray diffraction (XRD) pattern of/NC;
FIG. 11 shows MoO obtained in example 7 2 Transmission Electron Microscope (TEM) photographs (a), (b) and High Resolution Transmission Electron Microscope (HRTEM) photograph (c) of the NC composite material;
FIG. 12 is an X-ray diffraction (XRD) spectrum of a sample of the WP/NC catalyst prepared in example 8;
FIG. 13 is a Transmission Electron Microscope (TEM) photograph (a), (b) and a High Resolution Transmission Electron Microscope (HRTEM) photograph (c) of the WP/NC catalyst sample prepared in example 3;
FIG. 14 is a graph showing the polarization curves of the electrocatalytic hydrogen evolution reactions of the Mo-P/NC-600, moP/NC, and Mo-P/NC-800 catalyst samples prepared in examples 2-4 in 0.5M dilute sulfuric acid electrolyte;
FIG. 15 is a graph comparing polarization curves of electrocatalytic hydrogen evolution reactions of MoP/NC, moP bulk, NC and 20wt% Pt/C catalyst samples prepared in examples 2, 5, 6, 9 in 0.5M dilute sulfuric acid electrolyte;
FIG. 16 is a graph showing the comparison of the long-cycle cyclic voltammetry (a) and potentiostatic electrolytic stability (b) of hydrogen evolution reactions in 0.5M dilute sulfuric acid electrolyte for MoP/NC prepared in example 2 and MoP bulk prepared in example 5;
FIG. 17 is a graph of polarization of electrocatalytic hydrogen evolution reaction (a) and a graph of potentiostatic electrolytic stability (b) of the WP/NC catalyst sample prepared in example 8 in 0.5M dilute sulfuric acid electrolyte;
FIG. 18 is an exemplary flow chart for preparing a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material in accordance with the present application.
Detailed Description
For a further understanding of the present application, preferred embodiments of the application are described below in conjunction with the examples, but it should be understood that these descriptions are merely intended to illustrate further features and advantages of the application, and are not limiting of the claims of the application.
In view of the problems of agglomeration of active components and the like in the prior art, which affect the electrocatalytic performance of a phosphide-loaded carbon-based material as an electrocatalyst, the application provides a preparation method of a phosphide-nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, which leads to complete retention of three-dimensional porous morphology and avoids falling and agglomeration of phosphide by introducing a template agent and loading in situ, thereby leading to excellent electrocatalytic hydrogen evolution activity and long-term stability of the composite material as an electrocatalyst hydrogen evolution catalyst. Specifically, the embodiment of the application discloses a preparation method of a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material, which comprises the following steps:
a) Mixing a template agent, a surfactant, a carbon source capable of ionizing ammonium ions and a metal source, and freeze-drying the obtained mixed solution to obtain a precursor; the metal source is selected from a tungsten source or a molybdenum source;
b) Carrying out pyrolysis treatment on the precursor to obtain a nitrogen-doped three-dimensional carbon network composite material loaded with metal oxide nano particles;
c) And carrying out heat treatment on the nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nano particles and a phosphorus source to obtain the nitrogen-doped three-dimensional carbon network composite material loaded with the phosphide nano particles.
In the preparation process of the nitrogen-doped three-dimensional carbon network composite material loaded with phosphide nano particles, the preparation method comprises the steps of firstly mixing a template agent, a surfactant, a carbon source capable of ionizing ammonium ions and a metal source, and freeze-drying the obtained mixed solution to obtain a precursor; in this process, the template agent is selected from sodium chloride or potassium chloride, the surfactant is selected from PVP-K30, the molybdenum source is selected from one or more of ammonium heptamolybdate tetrahydrate, sodium molybdate and potassium molybdate, and the tungsten source is selected from one or more of potassium tungstate dihydrate, ammonium tungstate and sodium tungstate dihydrate; the carbon source is selected from one or more of glucosamine hydrochloride, N-methyl-D-glucosamine, D-galactosamine and N-acetylglucosamine; in a specific embodiment, the templating agent is selected from sodium chloride, the molybdenum source is selected from ammonium heptamolybdate tetrahydrate, the tungsten source is selected from sodium tungstate dihydrate, and the carbon source is selected from glucosamine hydrochloride. The mass ratio of the carbon source to the metal source is 1 (0.5-2), and the mass ratio of the template agent to the surfactant to the carbon source is 10 (0.1-0.5) (0.5-2); specifically, the mass ratio of the carbon source to the metal source is 1 (1.0-1.5), and the mass ratio of the template agent to the surfactant to the carbon source is 10 (0.2-0.3) to 1.0-1.5. The application specifically adopts liquid nitrogen to freeze the mixed solution.
In the process of preparing the precursor, positively charged ammonium ions formed by ionization of negatively charged molybdate ions (tungstate ions) and a carbon source are stably combined with a template agent through electrostatic action, the template agent is in a body-centered cubic structure, tiny cubes are formed on microcosmic scale after freeze drying crystallization, and the surfactant PVP-K30 can play roles in reducing the size of the template agent and inhibiting agglomeration; the mixed solution is subjected to freeze drying to remove the solvent, so that a uniform and stable precursor on a microscopic scale is formed.
The precursor is subjected to pyrolysis treatment to obtain the nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nano particles; in the process, along with the rise of the pyrolysis temperature, molybdate or tungstate is heated and decomposed into molybdenum dioxide or tungsten dioxide, simultaneously, a carbon source and a surfactant are heated and decomposed into a carbon skeleton and are distributed around a template agent, and ammonium ions carried by the carbon source are doped into the carbon skeleton in situ in the form of nitrogen elements to form a nitrogen doped carbon skeleton; meanwhile, as the elements in the precursor are uniformly distributed, the molybdenum dioxide or tungsten dioxide is not agglomerated due to the finite field effect of the carbon skeleton, but is dispersed in the whole material in the form of tiny nano particles; and the template agent is used as a rigid hard template, and the template is removed after the material obtained after pyrolysis treatment is washed and centrifuged by clear water, so that the three-dimensional nitrogen-doped carbon network can be obtained, and the three-dimensional nitrogen-doped carbon network is uniformly loaded with fine molybdenum dioxide or tungsten dioxide nano particles. The pyrolysis treatment of the application specifically comprises the following steps: heating the precursor to 500-1000 ℃ at a heating rate of 2-10 ℃/min, preserving heat for 4-10 h, and cooling; the pyrolysis treatment is always carried out in high-purity nitrogen, and the flow rate is 20-100 cc/min; in a specific embodiment, the heating rate is specifically 4-8 ℃/min, the temperature is 500-800 ℃, the temperature is kept for 6-8 h, and the flow rate is 30-80 cc/min.
Finally, carrying out heat treatment on the obtained nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nanoparticles and a phosphorus source to obtain the nitrogen-doped three-dimensional carbon network composite material loaded with the phosphide nanoparticles. The phosphorus source can be specifically selected from anhydrous sodium hypophosphite; the mass ratio of the nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nano particles to the phosphoric acid is 0.05: (10-20). In order to avoid that other phosphorus sources influence the morphology of the composite material in the step, the application adopts sodium hypophosphite which is easy to decompose phosphine gas as the phosphorus source, and the excellent morphology of the nitrogen-doped three-dimensional carbon network composite material loaded with nano particles is well maintained through gas-solid reaction. The heating rate of the heat treatment is 2-10 ℃/min, the temperature is 600-1000 ℃ and the time is 1-5 h; specifically, the heating rate of the heat treatment is 5-8 ℃/min, the temperature is 700-1000 ℃ and the time is 2-5 h. For the molybdenum and tungsten-based precursors, at least 700 ℃ is needed to convert the molybdenum and tungsten-based precursors into corresponding phosphide, and phosphine gas starts to be decomposed from sodium hypophosphite at 200 ℃, if the temperature does not reach 700 ℃ by adopting flowing inert atmosphere, the sodium hypophosphite is likely to be decomposed, and no phosphine gas participates in the reaction along with the discharge of the flowing gas; therefore, the temperature of the heat treatment is preferably higher than 700 ℃, and the heat treatment must be performed in a closed inert atmosphere (nitrogen or argon).
The template agent is selected from sodium chloride, the molybdenum source is selected from ammonium heptamolybdate tetrahydrate, the tungsten source is selected from sodium tungstate dihydrate, the carbon source is selected from glucosamine hydrochloride, the surfactant is PVP-30K, the phosphorus source is anhydrous sodium hypophosphite, and the preparation flow diagram of the composite material is shown in figure 18.
The application also provides a phosphide nano-particle-loaded nitrogen-doped three-dimensional carbon network composite material prepared by the method, which comprises a nitrogen-doped three-dimensional carbon network and phosphide nano-particles loaded on the surface of the nitrogen-doped three-dimensional carbon network, wherein the phosphide nano-particles are selected from molybdenum phosphide or tungsten phosphide.
In the composite material, the particle size of the phosphide is 10-100 nm. The composite material comprises the following elements in percentage by mass: 25-40% of C, 1-5% of N, 5-10% of O, 30-50% of Mo or W and 10-20% of P.
The application also provides application of the phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material as a catalyst in electrocatalytic hydrogen evolution reaction. The electrocatalytic hydrogen evolution reaction is not particularly limited and may be carried out in a manner well known to those skilled in the art.
The nitrogen-doped three-dimensional carbon network composite material loaded with nitride nano particles has the following advantages:
(1) The application introduces a hard template and can prepare the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum dioxide (tungsten dioxide) nano particles by freeze drying and pyrolysis treatment; the obtained composite material can be in-situ converted into a nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum (tungsten) phosphide nano particles through phosphating treatment, the three-dimensional porous morphology of the composite material is well reserved, and the problem of reduced catalytic activity of the material caused by material agglomeration in the process of synthesizing the hydrogen evolution electrocatalyst is solved;
(2) In the phosphide nano-particle-loaded nitrogen-doped three-dimensional carbon network composite material prepared by the application, phosphide nano-particles are loaded on a nitrogen-doped three-dimensional carbon network framework in situ in the pyrolysis process of the composite material; therefore, phosphide nano particles are not easy to fall off in the process of participating in electrocatalytic hydrogen evolution reaction, and the long-acting stability of the catalyst is ensured;
(3) The characteristic overpotential of the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum phosphide nano particles, which is prepared by the application, is 130mV lower than the characteristic overpotential of the bulk molybdenum phosphide bulk hydrogen evolution electrocatalyst by 61mV, and the nitrogen-doped three-dimensional carbon network composite material loaded with molybdenum phosphide nano particles shows excellent electrocatalytic hydrogen evolution activity;
(4) The nitrogen-doped three-dimensional carbon network hydrogen evolution electrocatalyst loaded with molybdenum phosphide nano particles prepared by the application has excellent long-term stability, and after a continuous 3000-cycle hydrogen evolution reaction electrocatalyst test, the overpotential is increased by 6mV; after constant potential electrolysis for 20 hours, the output current density retention rate of the nitrogen-doped three-dimensional carbon network compound loaded with molybdenum phosphide nano particles as an electrocatalyst is up to 88%, so that the electrochemical stability of the molybdenum phosphide hydrogen evolution electrocatalyst is improved;
(5) The nitrogen-doped three-dimensional carbon network composite material loaded with the tungsten phosphide nano particles prepared by the application is used as the characteristic overpotential 217mV of an electrocatalyst, and after 10h of constant potential electrolysis, the output current density retention rate of the nitrogen-doped three-dimensional carbon network loaded with the molybdenum phosphide nano particles is 75%, and the nitrogen-doped three-dimensional carbon network composite material shows excellent electrocatalytic hydrogen evolution activity and long-acting stability;
(6) The material is prepared from cheap and low-toxicity raw materials, has low cost and no pollution, and the glucosamine hydrochloride can simultaneously provide a carbon source and a nitrogen source, so that the utilization efficiency of the raw materials is improved.
In order to further understand the present application, the nitrogen-doped three-dimensional carbon network composite material loaded with phosphide nanoparticles, the preparation method and the application thereof provided by the present application are described in detail below with reference to examples, and the scope of protection of the present application is not limited by the following examples.
Example 1
White precursor GlcN/Mo 7 O 24 6- The mass of glucosamine hydrochloride, ammonium heptamolybdate tetrahydrate, polyvinylpyrrolidone PVP-K30 and sodium chloride in PVP@NaCl is respectively 1g, 0.25g and 10g, the heat treatment temperature is 650 ℃, the heat preservation time is 6h, and the MoO is prepared 2 NC composite material
(1) 1.0g (NH) 4 ) 6 Mo 7 O 24 ·4H 2 O, 0.25g PVP-K30, 1.0g glucosamine hydrochloride and 10.0g NaCl are completely dissolved in 40mL deionized water; then, a sufficient amount of liquid nitrogen was poured into the above colorless solution to rapidly cool it, at which time a white bubble-like precursor (designated as GlcN/Mo was observed 7 O 24 6- PVP@NaCl) to precipitate; after the liquid nitrogen is volatilized completely, freeze-drying is carried out on the liquid nitrogen immediately, the temperature is set to be-50 ℃, and the heat preservation time is 2 days;
(2) Taking out the white bubble precursor GlcN/Mo 7 O 24 6- Grinding PVP@NaCl into fine powder, and performing pyrolysis treatment under high-purity nitrogen gas flow (flow rate of 30cc min -1 ) The temperature is set to 650 ℃, the heat preservation time is set to 6 hours, and the temperature rising rate is set to 5 ℃ for min -1 The method comprises the steps of carrying out a first treatment on the surface of the Collecting the product obtained after pyrolysis, washing with deionized water and absolute ethyl alcohol to completely remove sodium chloride template, oven drying, and recording the black solid as MoO 2 /NC。
FIG. 1 shows MoO obtained in this example 2 XRD spectrum of NC material sample; as can be seen from FIG. 1, a broader peak appears near the diffraction angle of 26 DEG, indicating that carbon material is generated during pyrolysis of the composite material, and other diffraction peaks are all similar to MoO 2 One-to-one correspondence to indicate MoO 2 Successful synthesis of composites with carbon materials. FIG. 2 shows MoO obtained in this example 2 Scanning Electron Microscope (SEM) photographs (a), transmission Electron Microscope (TEM) photographs (b), (c) and High Resolution Transmission Electron Microscope (HRTEM) photographs (d) of NC material samples; as shown in FIG. 2, the MoO was prepared 2 The NC material sample shows a good three-dimensional porous network structure, and MoO with the grain diameter of about 5nm is uniformly distributed in the three-dimensional network structure 2 Nanoparticles, and no obvious agglomeration; the lattice fringe spacing of the nanoparticles was about 0.244nm, which is comparable to MoO 2 The (200) crystal face corresponds to, further corroborates that the nanoparticle phase is MoO 2 。
Example 2
MoO prepared in example 1 2 And (3) phosphating the NC composite material to obtain the electrocatalyst at 600 ℃.
(1) 50mg of MoO prepared in example 1 was taken 2 NC with 1.5g NaH 2 PO 2 Respectively placing the two elongated burning boats in a tube furnace, wherein the interval is about 10cm;
(2) Setting the temperature to 600 ℃, keeping the temperature for 2 hours, and heating the mixture at a temperature rising rate of 5 ℃ for min -1 ；
(3) After natural cooling, the obtained sample was collected, washed and dried, and the obtained product was designated Mo-P/NC-600.
FIG. 3 is an XRD spectrum of a sample of the Mo-P/NC-600 catalyst prepared in this example; as can be seen from FIG. 3, at 600℃of the phosphating temperature, only a large broad peak around 26℃was observed for the Mo-P/NC-600 catalyst sample in the range of 10 to 80℃of the diffraction angle, which is comparable to MoO 2 The XRD pattern of NC corresponds to the broad diffraction peak of the carbon material, but no other distinct diffraction peak was found, indicating that amorphous molybdenum phosphide may be produced at this temperature. FIG. 4 is a Scanning Electron Microscope (SEM) photograph (a) of a sample of the Mo-P/NC-600 catalyst prepared in the example(b); as shown in FIG. 4, since the phosphating temperature is 600 ℃ lower than the pyrolysis temperature of the previous step, the morphology of Mo-P/NC-600 is well maintained, and the morphology of Mo-P/NC-600 is still maintained 2 And (3) a three-dimensional porous network structure similar to NC, and no obvious aggregation exists.
Example 3
MoO prepared in example 1 2 And (3) phosphating the NC composite material to obtain the electrocatalyst at 700 ℃.
(1) 50mg of MoO prepared in example 1 was taken 2 NC with 1.5g NaH 2 PO 2 Respectively placing the two elongated burning boats in a tube furnace, wherein the interval is about 10cm;
(2) Setting the temperature to 700 ℃, keeping the temperature for 2 hours, and heating the temperature for 5 ℃ for min -1 ；
(3) After natural cooling, the obtained sample was collected, washed and dried, and the obtained product was designated as MoP/NC.
FIG. 5 is an XRD spectrum of a MoP/NC catalyst sample prepared in this example; as can be seen from FIG. 5, the phosphated product has a more pronounced peak around the diffraction angle of 26℃which also indicates an enhanced degree of graphitization of the carbon in the phosphated product, and other diffraction peaks are uniform-corresponding to MoP standard cards, indicating MoO 2 MoO in NC 2 The components have been completely converted to MoP components and the phosphating products remain in the form of carbon composites. Fig. 6 is a Scanning Electron Microscope (SEM) photograph (a), transmission Electron Microscope (TEM) photographs (b), (c) and High Resolution Transmission Electron Microscope (HRTEM) photograph (d) of the MoP/NC material sample prepared in this example; as shown in FIG. 6, moP/NC retains MoO 2 The three-dimensional porous network structure of/NC, the MoP nano-particle size is about 10nm, no obvious agglomeration phenomenon exists, the lattice fringe spacing of the nano-particle is about 0.279nm, which corresponds to the MoP (100) crystal face and indicates MoO 2 Has been completely converted into MoP.
Fig. 7 is an XPS spectrum of N element in the MoP/NC catalyst sample prepared in this example, and as can be seen from fig. 7, three existing forms of nitrogen in the MoP/NC catalyst are pyridine nitrogen, pyrrole nitrogen and graphitized nitrogen, respectively.
Example 4
MoO prepared in example 1 2 /NCAnd phosphating the composite material to obtain the electrocatalyst at 800 ℃.
(1) 50mg of MoO prepared in example 1 was taken 2 NC with 1.5g NaH 2 PO 2 Respectively placing the two elongated burning boats in a tube furnace, wherein the interval is about 10cm;
(2) Setting the temperature to 800 ℃, keeping the temperature for 2 hours, and heating the mixture at a temperature rising rate of 5 ℃ for min -1 ；
(3) After natural cooling, the obtained sample was collected, washed and dried, and the obtained product was designated Mo-P/NC-800.
FIG. 3 is an XRD spectrum of a sample of the Mo-P/NC-800 catalyst prepared in this example; as can be seen from FIG. 3, the diffraction peaks of the Mo-P/NC-800 catalyst sample at 800℃for the phosphating temperature were uniform-corresponding to the MoP standard card, indicating MoO 2 MoO in NC 2 The composition had been completely converted to a MoP composition and the diffraction peak corresponding to the carbon material around 26 ° became smaller, indicating a decrease in the carbon material content at 800 ℃. FIG. 4 is a Scanning Electron Microscope (SEM) photograph (c) and (d) of a sample of the Mo-P/NC-600 catalyst prepared in the example; as shown in FIG. 4, when the phosphating temperature reached 800 ℃, mo-P/NC-800 exhibited an imperfect three-dimensional porous network structure accompanied by particle agglomeration and collapse of the material.
Example 5
MoO prepared in example 1 2 And (3) carrying out heat treatment on the NC composite material in air at 500 ℃, and then carrying out phosphating treatment on the obtained product to obtain the electrocatalyst.
(1) 100mg of MoO prepared in example 1 was taken 2 Placing NC in a square porcelain boat, transferring into a muffle furnace, setting the temperature in air atmosphere at 500 deg.C, keeping the temperature for 10h, and heating at 5 deg.C for min -1 ；
(2) Naturally cooling, collecting the obtained sample, washing and drying to obtain the product which is named MoO 2 bulk；
(3) Taking 50mg of the obtained MoO 2 bulk with 1.5g NaH 2 PO 2 Respectively placing the two elongated burning boats in a tube furnace, wherein the interval is about 10cm;
(4) Setting the temperature to 700 ℃, keeping the temperature for 2 hours, and heating the temperature for 5 ℃ for min -1 。
(5) After natural cooling, the resulting sample was collected, washed and dried, and the resulting product was designated as MoP bulk.
FIG. 8 is an XRD spectrum of a MoP bulk catalyst sample prepared in this example; as can be seen from FIG. 8, the diffraction peaks of the MoP bulk catalyst samples were uniform-corresponding to the MoP standard card, indicating MoO 2 The component had been completely converted to MoP component and no carbon material peak around 26℃indicating MoO at 500 ℃C 2 The carbon material in the NC composite material is completely removed. Fig. 9 is Scanning Electron Microscope (SEM) photographs (a), (b) of the MoP bulk catalyst samples prepared in this example. As shown in fig. 9, the MoP bulk material exhibited a micron-sized bulk structure due to the significant agglomeration of the molybdenum component caused by the lack of support and confinement of the carbon material.
Example 6
Similar to the preparation method of MoP/NC, the precursor solution is prepared without adding a molybdenum source, and the rest is kept unchanged, so that the prepared electrocatalyst is prepared.
(1) 0.25g PVP-K30, 1.0g glucosamine hydrochloride, and 10.0g NaCl were completely dissolved in 40mL deionized water; then, a sufficient amount of liquid nitrogen was poured into the above colorless precursor solution to rapidly cool it, at which time a white bubble-like precursor (noted GlcN/pvp@nacl) was observed to precipitate; after the liquid nitrogen is volatilized completely, freeze-drying is carried out on the liquid nitrogen immediately, the temperature is set to be-50 ℃, and the heat preservation time is 2 days;
(2) Taking out, grinding the white bubble precursor GlcN/PVP@NaCl into fine powder, and performing pyrolysis treatment under high-purity nitrogen gas flow (flow rate of 30cc min) -1 ) The temperature is set to 650 ℃, the heat preservation time is set to 6 hours, and the temperature rising rate is set to 5 ℃ for min -1 The method comprises the steps of carrying out a first treatment on the surface of the Collecting a product obtained after pyrolysis, and fully washing and drying the product by deionized water and absolute ethyl alcohol;
(3) Taking 50mg of the product obtained in the step (2) and 1.5g of NaH 2 PO 2 Respectively placing the two elongated burning boats in a tube furnace, wherein the interval is about 10cm;
(4) Setting the temperature to 700 ℃, keeping the temperature for 2 hours, and heating the temperature for 5 ℃ for min -1 ；
(5) After natural cooling, the obtained sample was collected, washed and dried, and the obtained product was designated NC.
FIG. 8 is an XRD spectrum of an NC catalyst sample prepared in this example; as can be seen from fig. 8, NC exhibits typical two diffraction broad peaks of around 26 ° and 43 °, which correspond to the (002) and (100) crystal planes of graphitized carbon, exhibiting a certain degree of graphitization. Fig. 9 is Scanning Electron Microscope (SEM) photographs (c) and (d) of NC catalyst samples prepared in this example. As shown in fig. 9, the NC catalyst sample exhibited a three-dimensional network structure, and defects and cracks were present on the carbon layer.
Example 7
White precursor GlcN/WO 4 2- The mass of glucosamine hydrochloride, sodium tungstate dihydrate, polyvinylpyrrolidone PVP-K30 and sodium chloride in PVP@NaCl is respectively 1g, 0.25g and 10g, the heat treatment temperature is 650 ℃, the heat preservation time is 6h, and the WO is prepared 2 NC composite material
(1) 1.0g of Na 2 WO 4 ·2H 2 O, 0.25g PVP-K30, 1.0g glucosamine hydrochloride and 10.0g NaCl are completely dissolved in 40mL deionized water; then, a sufficient amount of liquid nitrogen was poured into the above colorless solution to rapidly cool it, at which time a white bubble-like precursor was observed (noted as GlcN/WO 4 2- PVP@NaCl) to precipitate; after the liquid nitrogen is volatilized completely, freeze-drying is carried out on the liquid nitrogen immediately, the temperature is set to be-50 ℃, and the heat preservation time is 2 days;
(2) After removal, the white foam precursor GlcN/WO 4 2- Grinding PVP@NaCl into fine powder, and performing pyrolysis treatment under high-purity nitrogen gas flow (flow rate of 30cc min -1 ) The temperature is set to 650 ℃, the heat preservation time is set to 6 hours, and the temperature rising rate is set to 5 ℃ for min -1 The method comprises the steps of carrying out a first treatment on the surface of the Collecting the product obtained after pyrolysis, washing with deionized water and absolute ethanol to completely remove sodium chloride template, oven drying, and making black solid as WO 2 /NC；
FIG. 10 shows WO prepared in this example 2 XRD spectrum of NC material sample; as can be seen from FIG. 10, the diffraction angle of the light is around 26 DEGShows a wider peak, indicates that carbon materials are generated in the pyrolysis process of the composite material, and other diffraction peaks are equal to those of WO 2 One-to-one correspondence, indicating WO 2 Successful synthesis of composites with carbon materials. FIG. 11 shows WO prepared in this example 2 Transmission Electron Microscope (TEM) photographs (a), (b) and High Resolution Transmission Electron Microscope (HRTEM) photograph (c) of NC material sample; as shown in FIG. 11, WO is prepared 2 The NC material sample shows a good three-dimensional porous network structure, and WO with the particle diameter of about 20nm is uniformly distributed in the three-dimensional network structure 2 Nanoparticles, with partial agglomeration; the lattice fringe spacing of the nanoparticles was about 0.218nm, which is comparable to WO 2 The (210) crystal face corresponds to, further prove that the nanoparticle phase is WO 2 。
Example 8
WO prepared in example 7 2 And (3) phosphating the NC composite material to obtain the electrocatalyst at 700 ℃.
(1) 50mg of WO prepared in example 7 were taken 2 NC with 1.5g NaH 2 PO 2 Respectively placing the two elongated burning boats in a tube furnace, wherein the interval is about 10cm;
(2) Setting the temperature to 700 ℃, keeping the temperature for 2 hours, and heating the temperature for 5 ℃ for min -1 ；
(3) After natural cooling, the sample obtained was collected, washed and dried, and the product obtained was designated WP/NC.
FIG. 12 is an XRD spectrum of a sample of WP/NC catalyst prepared in this example; as can be seen from FIG. 12, the phosphated product has a more pronounced peak around the diffraction angle of 26℃which also indicates an enhanced degree of graphitization of the carbon in the phosphated product, and other diffraction peaks are uniform-corresponding to the WP standard card, indicating WO 2 WO in/NC 2 The components have been completely converted to WP components and the phosphating product is still present in the form of a carbon composite. FIG. 13 is a Transmission Electron Microscope (TEM) photograph (a) and (b) and a High Resolution Transmission Electron Microscope (HRTEM) photograph (c) of the WP/NC material sample prepared in the present example; as shown in FIG. 13, WP/NC retains WO 2 Three-dimensional porous network structure of/NC, WP nanoparticle size about 10nm, partial agglomeration phenomenon, and nanoparticleLattice fringe spacing of about 0.273nm, corresponding to the WP (102) crystal plane, indicates WO 2 Has been completely converted into WP.
Example 9 Hydrogen evolution Performance test with 20wt.% Pt/C commercial electrocatalyst (ETEK Co.) as a control
5mg of the Mo-P/NC-600, moP/NC, mo-P/NC-800, moP bulk, NC, WP/NC and 20wt.% Pt/C commercial electrocatalyst as a performance comparison prepared in examples 2 to 6 and example 8 were weighed and 20. Mu.L was added117 (-5 wt%) and 980 μl of absolute ethanol, and performing ultrasonic dispersion for 60min until a uniform and stable catalyst dispersion is formed; dripping 0.015ml of dispersion into platinum-carbon area of 0.0707cm -2 The glassy carbon electrode surface is dried at room temperature and then used as a working electrode; polarization curve testing of Mo-P/NC-600, moP/NC, mo-P/NC-800, moP bulk, NC, WP/NC and 20wt.% Pt/C as performance comparison was performed using an electrochemical workstation (CHI 760E), in a three electrode cell with a saturated calomel electrode as reference electrode, a graphite rod as counter electrode, a 0.5M dilute sulfuric acid solution as electrolyte, at a sweep rate of 5 mV/s.
FIG. 14 is a graph showing the polarization curves of hydrogen evolution reactions of the Mo-P/NC-600, moP/NC, mo-P/NC-800 catalyst samples prepared in examples 2 to 4 in 0.5M dilute sulfuric acid electrolyte; as can be seen from FIG. 14, when the phosphating temperature is 700 ℃, the MoP/NC catalytic performance is optimal, and when the phosphating temperature is higher or lower than the previous one, the electrocatalytic hydrogen evolution performance is reduced; as shown in FIG. 14, polarization curves of three materials (Mo-P/NC-600, moP/NC and Mo-P/NC-800) show a large difference in hydrogen evolution reactivity, and a 600 ℃ phosphating product Mo-P/NC-600 shows the lowest hydrogen evolution reactivity and has an initial overpotential eta onset Is 200mV, characteristic overpotential eta 10 The MoP component in the phosphorization product Mo-P/NC-800 at the temperature of 298mV and 800 ℃ has the highest crystallization degree, but has lower carbon content and collapse appearance, the hydrogen evolution reaction is secondary, and the initial overpotential eta is low onset Is 151mV, characteristic overpotential eta 10 The activity of the phosphine product MoP/NC hydrogen evolution reaction at the temperature of 700 ℃ is highest, and the initial overpotential eta is 222mV onset 75mV, specialOverpotential eta 10 130mV, compared with 600 ℃ and 800 ℃ phosphine product hydrogen evolution performance is greatly improved.
FIG. 15 is a graph comparing polarization curves of electrocatalytic hydrogen evolution reactions of samples of MoP/NC, moP bulk, NC, 20wt% Pt/C catalysts prepared in examples 2, 5, and 6 and the present example, respectively, in 0.5M dilute sulfuric acid electrolyte; as can be seen from FIG. 15, 20wt% Pt/C commercial electrocatalyst as a performance comparative example, commercial 20wt% Pt/C as a general standard had an initial overpotential η near 0 0 Very low characteristic overpotential eta 10 (30 mV), exhibiting excellent electrocatalytic hydrogen evolution reactivity; carbon-free MoP bulk catalyst sample initiation overpotential eta onset 121mV, characteristic overpotential eta 10 For 191mV, moP is an important component for providing electrocatalytic hydrogen evolution reaction activity, and the polarization curve of the catalytic hydrogen evolution reaction of the carbon-based catalyst NC without the metal component is slowly reduced along with the continuous increase of overpotential, so that the hydrogen evolution activity is negligible, and the HER activity is hardly provided by the carbon-based material; moP/NC catalyst sample initiation overpotential eta onset Is 75mV, characteristic overpotential eta 10 130mV, compared with MoP bulk and NC catalyst samples, the electrocatalytic hydrogen evolution performance is greatly improved.
FIG. 16 is a graph showing the comparison of the long-cycle cyclic voltammetry (a) and potentiostatic electrolytic stability (b) of a hydrogen evolution reaction of a MoP/NC catalyst sample prepared in example 2 and a MoP bulk electrocatalyst prepared in comparative example 5 in 0.5M dilute sulfuric acid electrolyte; as can be seen from fig. 16 (a), the overpotential is increased by 6mV after the electrocatalytic test of hydrogen evolution reaction for 3000 cycles, and the overpotential is increased by 14mV after the electrocatalytic test of hydrogen evolution reaction for 3000 cycles, which indicates that the MoP/NC prepared by the method has more excellent electrocatalytic stability of hydrogen evolution than MoP bulk; as can be seen from fig. 16 (b), the MoP bulk can only maintain 55% of the initial current after the constant potential electrolysis hydrogen evolution test for 20 hours, while the MoP/NC catalyst prepared in example 2 can still maintain 88% of the initial current after the same test, which indicates that the MoP/NC prepared in the application has excellent long-term catalytic stability.
FIG. 17 is an embodiment ofThe WP/NC catalyst sample prepared in example 8 has an electrocatalytic hydrogen evolution reaction polarization curve graph (a) and a potentiostatic electrolysis stability graph (b) in 0.5M dilute sulfuric acid electrolyte; as can be seen from FIG. 17, the WP/NC catalyst sample has an initial overpotential η onset 144mV, characteristic overpotential eta 10 The current retention rate of WP/NC reaches 75% after the constant potential electrolysis hydrogen evolution test for 10h is carried out for 217mV, so that the excellent hydrogen evolution activity and stability of WP/NC are shown, and the universal application of the preparation method of the three-dimensional porous composite hydrogen evolution electrocatalyst is embodied.
The above description of the embodiments is only for aiding in the understanding of the method of the present application and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the application can be made without departing from the principles of the application and these modifications and adaptations are intended to be within the scope of the application as defined in the following claims.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A preparation method of a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material comprises the following steps:
a) Mixing a template agent, a surfactant, a carbon source capable of ionizing ammonium ions and a metal source, and freeze-drying the obtained mixed solution to obtain a precursor; the metal source is selected from a tungsten source or a molybdenum source;
b) Carrying out pyrolysis treatment on the precursor to obtain a nitrogen-doped three-dimensional carbon network composite material loaded with metal oxide nano particles;
c) And carrying out heat treatment on the nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nano particles and a phosphorus source to obtain the nitrogen-doped three-dimensional carbon network composite material loaded with the phosphide nano particles.
2. The method of claim 1, wherein the template agent is selected from sodium chloride or potassium chloride, the surfactant is selected from PVP-K30, the molybdenum source is selected from one or more of ammonium heptamolybdate tetrahydrate, sodium molybdate and potassium molybdate, the tungsten source is selected from one or more of potassium tungstate, ammonium tungstate and sodium tungstate dihydrate, the carbon source is selected from one or more of glucosamine hydrochloride, N-methyl-D-glucosamine, D-galactosamine and N-acetylglucosamine, and the phosphorus source is selected from sodium hypophosphite.
3. The production method according to claim 1, wherein the mass ratio of the carbon source to the metal source is 1: (0.5-2), wherein the mass ratio of the template agent, the surfactant and the carbon source is 10: (0.1-0.5): (0.5-2); the mass ratio of the nitrogen-doped three-dimensional carbon network composite material loaded with the metal oxide nano particles to the phosphorus source is 0.05: (10-20).
4. The method according to claim 1, wherein in the step B), the pyrolysis treatment is performed under a protective atmosphere, which is high purity nitrogen.
5. The method according to claim 1, wherein in the step B), the pyrolysis treatment is performed at a temperature of 500 to 1000 ℃ for a time of 4 to 10 hours.
6. The method according to claim 1, wherein in the step C), the heating rate of the heat treatment is 2 to 10 ℃/min, the temperature is 600 to 1000 ℃ and the time is 1 to 5 hours.
7. A phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material prepared by the preparation method as set forth in any one of claims 1 to 6, comprising a nitrogen-doped three-dimensional carbon network and phosphide nanoparticles supported on the surface of the nitrogen-doped three-dimensional carbon network, wherein the phosphide nanoparticles are selected from molybdenum phosphide or tungsten phosphide.
8. The composite material of claim 7, wherein the phosphide nanoparticles have a particle size of from 10 to 100nm.
9. The composite material according to claim 7, wherein the mass percentages of the elements in the composite material are: 25-40% of C, 1-5% of N, 5-10% of O, 30-50% of Mo or W and 10-20% of P.
10. Use of a phosphide nanoparticle-loaded nitrogen-doped three-dimensional carbon network composite material prepared by the preparation method as claimed in any one of claims 1 to 6 or as claimed in any one of claims 7 to 9 as a catalyst in an electrocatalytic hydrogen evolution reaction.
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