CN114950397B - 一种三氟乙酸改性硅表面TFA-Si光催化剂及其制备方法和应用 - Google Patents
一种三氟乙酸改性硅表面TFA-Si光催化剂及其制备方法和应用 Download PDFInfo
- Publication number
- CN114950397B CN114950397B CN202210480871.2A CN202210480871A CN114950397B CN 114950397 B CN114950397 B CN 114950397B CN 202210480871 A CN202210480871 A CN 202210480871A CN 114950397 B CN114950397 B CN 114950397B
- Authority
- CN
- China
- Prior art keywords
- tfa
- photocatalyst
- trifluoroacetic acid
- silicon
- hcl
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- DTQVDTLACAAQTR-UHFFFAOYSA-N trifluoroacetic acid Substances OC(=O)C(F)(F)F DTQVDTLACAAQTR-UHFFFAOYSA-N 0.000 title claims abstract description 79
- 239000011941 photocatalyst Substances 0.000 title claims abstract description 55
- 238000002360 preparation method Methods 0.000 title claims abstract description 14
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 37
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 36
- 239000010703 silicon Substances 0.000 claims abstract description 35
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 34
- 239000001257 hydrogen Substances 0.000 claims abstract description 32
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 32
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 29
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 22
- 230000001699 photocatalysis Effects 0.000 claims abstract description 20
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 18
- 235000012239 silicon dioxide Nutrition 0.000 claims abstract description 18
- -1 trifluoroacetic acid modified silicon Chemical class 0.000 claims abstract description 14
- 238000000354 decomposition reaction Methods 0.000 claims abstract description 5
- 239000002243 precursor Substances 0.000 claims abstract description 4
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 22
- 239000000843 powder Substances 0.000 claims description 18
- 238000000034 method Methods 0.000 claims description 17
- 230000009467 reduction Effects 0.000 claims description 15
- 238000001354 calcination Methods 0.000 claims description 14
- 239000008367 deionised water Substances 0.000 claims description 14
- 229910021641 deionized water Inorganic materials 0.000 claims description 14
- 239000002244 precipitate Substances 0.000 claims description 13
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 12
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 11
- 239000000395 magnesium oxide Substances 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 8
- 229910052573 porcelain Inorganic materials 0.000 claims description 8
- 239000012300 argon atmosphere Substances 0.000 claims description 7
- 239000006227 byproduct Substances 0.000 claims description 7
- 238000002156 mixing Methods 0.000 claims description 7
- 239000004570 mortar (masonry) Substances 0.000 claims description 7
- 238000007654 immersion Methods 0.000 claims description 6
- 238000005580 one pot reaction Methods 0.000 claims description 6
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 3
- 229910052786 argon Inorganic materials 0.000 claims description 2
- 239000011148 porous material Substances 0.000 claims description 2
- 238000003756 stirring Methods 0.000 claims description 2
- 239000011863 silicon-based powder Substances 0.000 claims 2
- 239000007789 gas Substances 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 20
- 229910008051 Si-OH Inorganic materials 0.000 abstract description 10
- 229910006358 Si—OH Inorganic materials 0.000 abstract description 10
- 239000002210 silicon-based material Substances 0.000 abstract description 6
- 229910004298 SiO 2 Inorganic materials 0.000 abstract description 5
- 230000007774 longterm Effects 0.000 abstract description 5
- 231100000331 toxic Toxicity 0.000 abstract description 5
- 230000002588 toxic effect Effects 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 4
- 230000006798 recombination Effects 0.000 abstract description 3
- 238000005215 recombination Methods 0.000 abstract description 3
- 238000002386 leaching Methods 0.000 abstract description 2
- DFPWNNNCJDHVEY-UHFFFAOYSA-N [F].FC(C(=O)O)(F)F Chemical compound [F].FC(C(=O)O)(F)F DFPWNNNCJDHVEY-UHFFFAOYSA-N 0.000 abstract 1
- 239000002253 acid Substances 0.000 abstract 1
- 238000011946 reduction process Methods 0.000 abstract 1
- 238000005406 washing Methods 0.000 abstract 1
- 238000006722 reduction reaction Methods 0.000 description 14
- 230000000694 effects Effects 0.000 description 9
- 239000003054 catalyst Substances 0.000 description 8
- 238000002441 X-ray diffraction Methods 0.000 description 7
- 238000010438 heat treatment Methods 0.000 description 6
- 238000001069 Raman spectroscopy Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 3
- 238000003421 catalytic decomposition reaction Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910052731 fluorine Inorganic materials 0.000 description 3
- 150000002431 hydrogen Chemical class 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- 229910052749 magnesium Inorganic materials 0.000 description 3
- 238000001000 micrograph Methods 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 150000003376 silicon Chemical class 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 2
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 2
- 229910018557 Si O Inorganic materials 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000011737 fluorine Substances 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000007146 photocatalysis Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000004098 selected area electron diffraction Methods 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Inorganic materials [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910008284 Si—F Inorganic materials 0.000 description 1
- 238000003917 TEM image Methods 0.000 description 1
- 238000010306 acid treatment Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000002362 energy-dispersive X-ray chemical map Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 125000000524 functional group Chemical group 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002329 infrared spectrum Methods 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 238000002371 ultraviolet--visible spectrum Methods 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
- B01J21/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/04—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing carboxylic acids or their salts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
- B01J35/39—Photocatalytic properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/64—Pore diameter
- B01J35/647—2-50 nm
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/64—Pore diameter
- B01J35/651—50-500 nm
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0201—Impregnation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/08—Heat treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/16—Reducing
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
- C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
- C01B3/04—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by decomposition of inorganic compounds, e.g. ammonia
- C01B3/042—Decomposition of water
-
- 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
-
- 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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/30—Wastewater or sewage treatment systems using renewable energies
- Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Combustion & Propulsion (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Catalysts (AREA)
Abstract
本发明公开了一种三氟乙酸改性硅表面TFA‑Si光催化剂及其制备方法和应用。该光催化剂以二氧化硅作为前驱体,通过低温镁热还原过程,经由HCl酸洗和三氟乙酸酸浸,在硅材料表面进行吸附有机氟三氟乙酸,得到TFA‑Si光催化剂。本发明引入的三氟乙酸具有强电负性,能够有效吸收光生电子,减少电子空穴的复合,从而提高光催化活性。且三氟乙酸循环吸附在硅表面,能够保护Si–OH不被氧化成SiO2,进而降低硅表面SiO2的生成速率,进一步提高了光催化剂的产氢稳定性。所得处理材料与单纯硅相比,光催化分解水产氢性能显著提高,且能够在纯水条件下表现出优异的产氢稳定性。重要的是,避免使用有毒的HF具有长期的生态意义。
Description
技术领域
本发明属于光催化材料技术领域,具体涉及一种三氟乙酸改性硅表面(TFA-Si)光催化剂的制备方法及其可见光诱导催化分解纯水产氢应用。
背景技术
氢由于其清洁、可再生、高能量密度和可运输性等优点,一直被认为是化石燃料的理想替代品。然而,目前氢能生产技术效率低、能耗高、环境危害性大,严重制约了氢能的商业化应用。因此,吸收源源不断的太阳光在纯水中直接分解水产氢,是缓解全球能源短缺和环境问题的可持续途径。硅是地球上含量第二丰富的元素,价格低廉,容易获得,被认为是光催化制氢的合适半导体,但电荷分离效率低以及稳定性差限制了其实际应用,因此需要对其进行改性。
氟作为最稳定的终结剂,具有较强的电负性,能有效吸收光生电子,减少电子空穴的重组,从而提高光催化活性。正如HF处理硅的目的是为了提高硅光催化剂的光催化性能,由于Si–F终止效应的影响,硅光催化剂具有良好的稳定性。然而,由于其具有腐蚀性,需要牺牲硅才能产生孔洞,因此硅的高质量损耗以及需要大量有毒的HF,使得该方法成本高、效率低。因此有必要采用成本低、微毒的氟源来取代剧毒HF的使用,利用表面官能团保护提高电荷分离效率,促进光催化产氢性能。
发明内容
本发明的目的在于为设计更高效的光催化体系,而提供的一种三氟乙酸改性硅表面(TFA-Si)光催化剂的制备方法及其可见光诱导催化分解纯水产氢应用。本发明引入的三氟乙酸具有强电负性,能够有效吸收光生电子,减少电子空穴的复合,且三氟乙酸循环吸附在硅催化剂表面上,能够保护Si–OH不被氧化成SiO2,进而降低硅表面SiO2的生成速率,使其在光催化分解水产氢中表现出优异的活性以及稳定性。
为实现上述目的,本发明采用如下技术方案:
一种三氟乙酸改性硅表面(TFA-Si)光催化剂,是由二氧化硅作为前驱体进行镁热还原制备的硅作为载体,在其表面通过吸附三氟乙酸而构成的;其中,TFA-Si粒径大小范围为5–20 µm,孔径大小为10–200 nm。所述TFA-Si 中,三氟乙酸与硅的摩尔比值为1%。
所述三氟乙酸改性硅表面(TFA-Si)光催化剂的制备方法包括以下步骤:
(1)一锅镁热还原法制备HCl-Si:
二氧化硅与镁粉在研钵中均匀混合,然后,将混合物转移到瓷舟中,放在氩气气氛下管式炉中煅烧,氩气流速为100 mL/min,加热时间为3 h;待温度降至50℃后,然后向生成的粉末中缓慢加入HCl溶液,室温下搅拌5小时以去除副产物,所得沉淀用去离子水多次洗涤后于60 ℃真空干燥过夜,得到HCl-Si粉末;
(2)浸渍法制备TFA-Si光催化剂:
将所得HCl-Si粉末分散于三氟乙酸溶液中,并以相同的转速搅拌60 min。所得沉淀用去离子水和乙醇各洗涤三次后于60℃真空干燥过夜,得到所述TFA-Si光催化剂。
步骤(1)镁热还原煅烧过程中,煅烧温度范围为550℃–850℃。
步骤(2)中所用三氟乙酸溶液浓度为0.5 mol/L;
在浸渍处理过程中,由二氧化硅作为前驱体进行镁热还原制备的硅作为载体,在其表面吸附三氟乙酸,从而最终形成TFA-Si结构。
所得三氟乙酸改性硅表面(TFA-Si)光催化剂可用于光催化分解纯水产氢。
本发明的显著优点在于:
(1)本发明提供了一种镁热还原法加三氟乙酸酸浸法制备硅光催化剂的策略,本发明原料来源丰富、成本低,制备方法简单安全,无需贵金属,避免了化学原料及能源的过渡消耗,可大规模推广。
(2)本发明首次将三氟乙酸引入硅基光催化剂,构建了表面吸附三氟乙酸的TFA-Si光催化剂。突破了传统硅催化剂使用强腐蚀性氢氟酸刻蚀表面除去Si–O维持稳定性的长期困境,为高效硅基光催化体系的设计提供了新思路。传统HF处理硅材料的目的在于去除表面氧化物使得硅表面暴露更多的活性位点进行光催化产氢。但由于硅表面氧化速度很快,反应几个小时后表面就覆盖了氧化物膜造成光催化剂无法继续产氢。而使用牺牲剂如甲醇的目的在于消耗光生空穴,避免光生空穴氧化硅形成氧化物,促进光催化产氢。本发明中引入的TFA分子易与Si–OH结合生成CF3COOSi复合物。在光照过程中,该复合物在体系H+和光生电子的作用下,会转化成Si和TFA分子。使得硅表面再次暴露出活性位点利用光催化产氢,而TFA分子则会再次吸附在Si–OH进行下一次的循环。TFA-Si结构能够保护Si–OH不被继续氧化成SiO2,并且提供活性位点促进光催化产氢。利用TFA的保护作用,无需牺牲剂捕获空穴就能有较好的产氢稳定性能。可以有效地将太阳能转化为化学能,具有较高的实际应用价值。
(3)本发明用微毒性三氟乙酸取代剧毒强腐蚀性HF的使用,实验安全程度高,且具有长期的生态意义。
附图说明
图1为本发明实施例3中的无处理硅(Si)、HCl处理硅(HCl-Si)及三氟乙酸改性硅(TFA-Si)光催化剂的X射线衍射图(XRD);
图2 为本发明实施例3中的三氟乙酸改性硅(TFA-Si)材料的扫描电镜(SEM)、透射电镜图(TEM)和选区元素分布图(EDX-mapping);
图3为本发明实施例3中无三氟乙酸处理硅(Si)和有三氟乙酸改性硅(TFA-Si)的红外、拉曼对比图;
图4中为本发明实施例1-4中不同煅烧温度下制备TFA-Si光催化剂的产氢速率图。
图5中(a)为本发明实施例3中的TFA-Si不同波长下的量子效率以及其紫外可见光谱图;(b)为本发明实施例3中的TFA-Si光催化剂的长时间产氢循环实验图。
图6为本发明中TFA-Si光催化剂可能的产氢反应机理图。
具体实施方式
为了使本发明所述的内容更加便于理解,下面结合具体实施方式对本发明所述的技术方案做进一步的说明,但是本发明不仅限于此。
实施例1
(1)一锅镁热还原法制备HCl-Si载体:
二氧化硅(SiO2)与镁粉按1:2的摩尔比在研钵中均匀混合。然后,将混合物转移到一个小瓷舟中,瓷舟放在氩气气氛下管式炉。煅烧温度为550℃,流速为100 mL/min,加热时间为3 h。待温度降至50℃后,取出样品Si。然后向生成的粉末中缓慢加入HCl溶液,室温下搅拌5小时以去除副产物。所得沉淀用去离子水多次洗涤后于60℃真空干燥过夜,得到HCl-Si粉末。
(2)浸渍法制备TFA-Si光催化剂:
将所得HCl-Si粉末70 mg分散于0.5 M三氟乙酸溶液中,并以相同的速度搅拌60min。所得沉淀用去离子水和乙醇各洗涤三次后于60℃真空干燥过夜,得到所述TFA-Si光催化剂(TFA与Si的摩尔比值为1%)。
实施例2
(1)一锅镁热还原法制备HCl-Si载体:
二氧化硅(SiO2)与镁粉按1:2的摩尔比在研钵中均匀混合。然后,将混合物转移到一个小瓷舟中,瓷舟放在氩气气氛下管式炉。煅烧温度为650℃,流速为100 mL/min,加热时间为3 h。待温度降至50℃后,取出样品Si。然后向生成的粉末中缓慢加入HCl溶液,室温下搅拌5小时以去除副产物。所得沉淀用去离子水多次洗涤后于60℃真空干燥过夜,得到HCl-Si粉末。
(2)浸渍法制备TFA-Si光催化剂:
将所得HCl-Si粉末70 mg分散于0.5 M三氟乙酸溶液中,并以相同的速度搅拌60min。所得沉淀用去离子水和乙醇各洗涤三次后于60℃真空干燥过夜,得到所述TFA-Si光催化剂(TFA与Si的摩尔比值为1%)。
实施例3
(1)一锅镁热还原法制备HCl-Si载体:
二氧化硅(SiO2)与镁粉按1:2的摩尔比在研钵中均匀混合。然后,将混合物转移到一个小瓷舟中,瓷舟放在氩气气氛下管式炉。煅烧温度为750℃,流速为100 mL/min,加热时间为3 h。待温度降至50℃后,取出样品Si(即无处理硅Si)。然后向生成的粉末中缓慢加入HCl溶液,室温下搅拌5小时以去除副产物。所得沉淀用去离子水多次洗涤后于60℃真空干燥过夜,得到HCl-Si粉末。
(2)浸渍法制备TFA-Si光催化剂:
将所得HCl-Si粉末70 mg分散于0.5 M三氟 乙酸溶液中,并以相同的速度搅拌60min。所得沉淀用去离子水和乙醇各洗涤三次后于60℃真空干燥过夜,得到所述TFA-Si光催化剂(TFA与Si的摩尔比值为1%)。
实施例4
(1)一锅镁热还原法制备HCl-Si载体:
二氧化硅(SiO2)与镁粉按1:2的摩尔比在研钵中均匀混合。然后,将混合物转移到一个小瓷舟中,瓷舟放在氩气气氛下管式炉。煅烧温度为850℃,流速为100 mL/min,加热时间为3 h。待温度降至50℃后,取出样品Si。然后向生成的粉末中缓慢加入HCl溶液,室温下搅拌5小时以去除副产物。所得沉淀用去离子水多次洗涤后于60℃真空干燥过夜,得到HCl-Si粉末。
(2)浸渍法制备TFA-Si光催化剂:
将所得HCl-Si粉末70 mg分散于0.5 M三氟乙酸溶液中,并以相同的速度搅拌60min。所得沉淀用去离子水和乙醇各洗涤三次后于60℃真空干燥过夜,得到所述TFA-Si光催化剂(TFA与Si的摩尔比值为1%)。
对比例1
二氧化硅(SiO2)与镁粉按1:2的摩尔比在研钵中均匀混合。然后,将混合物转移到一个小瓷舟中,瓷舟放在氩气气氛下管式炉。煅烧温度为750℃,流速为100 mL/min,加热时间为3 h。待温度降至50℃后,取出样品Si。然后向生成的粉末中缓慢加入HCl溶液,室温下搅拌5小时以去除副产物。所得沉淀用去离子水多次洗涤后于60℃真空干燥过夜,得到HCl-Si粉末。
应用例
将实施例1–4所得TFA-Si光催化剂分别用于可见光诱导催化分解纯水产氢,其具体步骤为:称取10 mg催化剂样品,加入到50 mL去离子水中,将该溶液置于光催化产氢系统中,由恒温循环冷凝水控制反应温度5℃,待系统抽真空后,开启氙灯光源进行光催化分解水产氢,产生氢气的量通过气相色谱检测。
图1为本发明实施例3中的镁热还原制备的未处理硅(Si)、HCl处理硅(HCl-Si)及三氟乙酸改性硅(TFA-Si)光催化剂的X射线衍射图(XRD)。由图1可知,HCl-Si只有纯硅相而没有其他MgO,说明HCl能够充分的除去杂质MgO。TFA-Si光催化剂与HCl-Si的X射线衍峰一致,说明了三氟乙酸处理前后未改变硅材料的化学组成,且其X射线衍射峰与对应标准XRD卡片相匹配,说明了催化剂纯硅相的成功制备。
图2 为本发明实施例3中的三氟乙酸改性硅(TFA-Si)光催化剂的扫描电镜图、透射电镜图以及透射电镜选区元素分布图。其中a–c是TFA-Si的扫描电镜图,从图中可见,TFA-Si粒径大小为5–20 µm。d–e和g是TFA-Si的透射电镜图,可以看出TFA-Si具有无序的大孔结构。选定区域电子衍射(SAED)图(e中插图)表明,TFA-Si样品具有较高的结晶度,f中可以看出晶格间距为0.32 nm。对应的EDX映射图(h–i)表明Si、F元素分布均匀。
图3 为本发明实施例3中的HCl-Si和TFA-Si光催化剂的红外和拉曼图。图3的(a)中1628 cm−1 和 1426 cm−1为碳基(C=O)的特征峰,这是经三氟乙酸处理的硅光催化所特有的红外信号,表明三氟乙酸成功引入硅材料上。但由于Si–O所在红外位置范围太大(1300cm−1–1000 cm−1),使得位于1145 cm−1和1200 cm−1位置的C–F未在红外谱图中体现。图3的(b)拉曼图体现出制备的硅材料结晶度高,无非晶硅峰。且处理后拉曼硅峰向体硅方向移动,说明TFA处理后样品具有更高的结晶度。
图4中为本发明实施例1-4中不同煅烧温度下制备TFA-Si光催化剂的产氢速率图。可以看出,硅材料的产氢活性随镁热还原温度的不同而呈现一定的趋势,在750℃是催化剂具有最高活性1827 µmol·g−1·h−1。因为金属镁的熔点在650℃,因此低于650℃的镁热还原反应无法将Si置换出来。而温度过高则会导致Si的结构被破坏。因此在750℃下进行的镁热还原反应制备出来的TFA-Si样品具有最佳的光催化产氢活性。
图5中(a)为本发明实施例3中的TFA-Si光催化剂不同波长下的量子效率。其中可见光400 nm下量子效率最高有6.1%,具有较好的太阳能利用率。(b)本发明实施例3中的TFA-Si光催化剂的长时间产氢循环实验图。由图中可见,在五个光照反应循环(共20 h)后,复合催化剂的活性仅略有下降,表明该催化剂具有较好的稳定性。
图6为本发明实施例3中的TFA-Si光催化剂可能的产氢机理图。光生空穴能够将Si氧化成Si–OH并释放出H+,如果再进一步氧化则会成为SiO2。而光生电子将H+还原成H2析出。而吸附在硅表面的TFA分子会和Si–OH键合生成CF3COOSi结构。该结构在电子和体系H+的作用下会转化成Si和TFA分子。Si可以再次被氧化成Si–OH,而TFA分子可以再次和Si–OH键合,从而起到保护Si–OH不被氧化成SiO2的目的。
表1
表1为本发明与近期报道的相关光催化剂的活性对比,本发明的光催化剂具有明显较高的产氢活性。
以上所述仅为本发明的较佳实施例,凡依本发明申请专利范围所做的均等变化与修饰,皆应属本发明的涵盖范围。
Claims (7)
1.一种三氟乙酸改性硅表面TFA-Si光催化剂,其特征在于:该光催化剂是由二氧化硅作为前驱体进行镁热还原制备的硅作为载体,在其表面通过吸附三氟乙酸而构成;所述TFA-Si粒径大小范围为5–20 µm,孔径大小为10–200 nm;所述TFA-Si 中,三氟乙酸与硅的摩尔比值为1%。
2.一种如权利要求1所述的三氟乙酸改性硅表面TFA-Si光催化剂的制备方法,其特征在于:包括以下步骤:
(1)一锅镁热还原法制备HCl-Si:
二氧化硅与镁粉在研钵中均匀混合,然后,将混合物转移到瓷舟中,放在氩气气氛下管式炉中煅烧;待温度降至50℃后,然后向生成的粉末中缓慢加入HCl溶液,室温下搅拌5小时以去除副产物,所得沉淀用去离子水多次洗涤后于60 ℃真空干燥过夜,得到HCl-Si粉末;
(2)浸渍法制备TFA-Si光催化剂:
将所得HCl-Si粉末分散于三氟乙酸溶液中,搅拌60 min,所得沉淀用去离子水和乙醇各洗涤三次后于60 ℃真空干燥过夜,得到所述TFA-Si光催化剂。
3.根据权利要求2所述的三氟乙酸改性硅表面TFA-Si光催化剂的制备方法,其特征在于:步骤(1)中二氧化硅与镁粉的摩尔比为1:2。
4.根据权利要求2所述的TFA-Si光催化剂的制备方法,其特征在于:步骤(1)中氩气气体流速为100 mL/min。
5.根据权利要求2所述的TFA-Si光催化剂的制备方法,其特征在于:步骤(1)中镁热还原煅烧过程中,煅烧时间为3 h,煅烧温度为550-850℃。
6.根据权利要求2所述的TFA-Si光催化剂的制备方法,其特征在于:步骤(2)中加入的三氟乙酸溶液的浓度为0.5 mol/L。
7.一种如权利要求1所述的三氟乙酸改性硅表面TFA-Si光催化剂在光催化分解水产氢中的应用。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210480871.2A CN114950397B (zh) | 2022-05-05 | 2022-05-05 | 一种三氟乙酸改性硅表面TFA-Si光催化剂及其制备方法和应用 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210480871.2A CN114950397B (zh) | 2022-05-05 | 2022-05-05 | 一种三氟乙酸改性硅表面TFA-Si光催化剂及其制备方法和应用 |
Publications (2)
Publication Number | Publication Date |
---|---|
CN114950397A CN114950397A (zh) | 2022-08-30 |
CN114950397B true CN114950397B (zh) | 2023-08-04 |
Family
ID=82982390
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210480871.2A Active CN114950397B (zh) | 2022-05-05 | 2022-05-05 | 一种三氟乙酸改性硅表面TFA-Si光催化剂及其制备方法和应用 |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN114950397B (zh) |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6074981A (en) * | 1996-08-05 | 2000-06-13 | Nippon Sheet Glass Co., Ltd. | Photocatalyst and process for the preparation thereof |
JP2002028494A (ja) * | 1997-04-02 | 2002-01-29 | Nippon Sheet Glass Co Ltd | 光触媒担持体およびその製造方法 |
CN1438071A (zh) * | 2003-03-13 | 2003-08-27 | 武汉理工大学 | 表面氟化处理增强二氧化钛光催化活性的方法 |
CN110171832A (zh) * | 2019-06-20 | 2019-08-27 | 浙江工业大学 | 一种基于金属氢化物还原制备多孔硅的方法 |
-
2022
- 2022-05-05 CN CN202210480871.2A patent/CN114950397B/zh active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6074981A (en) * | 1996-08-05 | 2000-06-13 | Nippon Sheet Glass Co., Ltd. | Photocatalyst and process for the preparation thereof |
JP2002028494A (ja) * | 1997-04-02 | 2002-01-29 | Nippon Sheet Glass Co Ltd | 光触媒担持体およびその製造方法 |
CN1438071A (zh) * | 2003-03-13 | 2003-08-27 | 武汉理工大学 | 表面氟化处理增强二氧化钛光催化活性的方法 |
CN110171832A (zh) * | 2019-06-20 | 2019-08-27 | 浙江工业大学 | 一种基于金属氢化物还原制备多孔硅的方法 |
Non-Patent Citations (1)
Title |
---|
A highly fluorine-functionalized 2D covalent organic framework for promoting photocatalytic hydrogen evolution;Cheng Liu,et al.;《Applied Surface Science》;第537卷;148082 * |
Also Published As
Publication number | Publication date |
---|---|
CN114950397A (zh) | 2022-08-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN109876841B (zh) | 一种2-氨基对苯二甲酸和胺化合物共聚合制备石墨相氮化碳可见光催化剂的方法 | |
CN113663693B (zh) | 一种硫化铟锌-二氧化钛复合材料的制备方法及其在生产双氧水用于废水治理中的应用 | |
CN110342477B (zh) | 一种氧掺杂多孔氮化碳纳米片及其制备方法 | |
CN112156770B (zh) | 一种具有铋、氧双空位的钨酸铋复合光催化剂及其制备方法和应用 | |
CN111203262B (zh) | 快速制备氮化碳纳米片负载纳米铜的方法及其产品和应用 | |
CN110961133B (zh) | 非金属BCN/g-C3N4范德华异质结光催化剂及其制备方法和应用 | |
CN113663705B (zh) | 一种钒酸镧/石墨相氮化碳复合材料及其制备方法和应用 | |
CN108525695B (zh) | 一种二维层状结构的石墨烯/碳氮烯/溴氧铋复合纳米光催化材料及其制备方法和应用 | |
CN113713796B (zh) | 一种Ni-NiO/C-TiO2核壳结构纳米棒状材料光催化剂的制备方法 | |
CN112479248B (zh) | 一种锶空位可调的钛酸锶的制备方法及其在光催化制氢领域的应用 | |
CN113976165A (zh) | 一种铋钨酸盐与氮化碳复合光催化材料的制备及应用 | |
CN112047372B (zh) | 一种CuO多孔纳米片、其制备方法及其在热催化和光热催化方面的应用 | |
CN112371113A (zh) | 一种Bi2WO6-rGO可见光催化剂的制备方法和应用 | |
CN115999614B (zh) | 一种紫外-可见-近红外光响应的二氧化碳还原光催化剂 | |
CN114950397B (zh) | 一种三氟乙酸改性硅表面TFA-Si光催化剂及其制备方法和应用 | |
CN109847753B (zh) | 一种多孔Co@C纳米材料及其制备方法和应用 | |
CN116903021A (zh) | 一种多孔氧化铈纳米片催化剂及其制备和在光热协同二氧化碳分解反应中的应用 | |
CN113877556B (zh) | 羟基氧化铟/改性凹凸棒石光催化复合材料及其制备方法和应用 | |
CN112844375B (zh) | 脱除氮氧化物的MnO2/Bi2WO6异质结光催化剂及其制备方法 | |
CN114870873A (zh) | 一种用离子交换构建表面缺陷光催化材料的方法 | |
CN114768852A (zh) | 一种钾离子梯度掺杂氮化碳材料的制备方法 | |
CN111468133A (zh) | 一种铌酸钾/α-氧化铁异质光催化剂的制备方法 | |
CN117427643B (zh) | 一种基于石墨相氮化碳的光催化材料及其制备方法和应用 | |
CN115646530B (zh) | 一种双促进型硼掺杂手风琴状石墨氮化碳光催化剂及其制备方法、应用 | |
CN114917919B (zh) | 一种铋钨钴多酸盐与氮化碳复合光催化材料及其制备方法和应用 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |