CN116040595A - 过渡金属磷化物/C/MXene复合材料的制备方法 - Google Patents
过渡金属磷化物/C/MXene复合材料的制备方法 Download PDFInfo
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- CN116040595A CN116040595A CN202310063766.3A CN202310063766A CN116040595A CN 116040595 A CN116040595 A CN 116040595A CN 202310063766 A CN202310063766 A CN 202310063766A CN 116040595 A CN116040595 A CN 116040595A
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- mxene
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- 239000002131 composite material Substances 0.000 title claims abstract description 30
- 229910052723 transition metal Inorganic materials 0.000 title claims abstract description 28
- 150000003624 transition metals Chemical class 0.000 title claims abstract description 18
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 239000012621 metal-organic framework Substances 0.000 claims abstract description 21
- 229910001415 sodium ion Inorganic materials 0.000 claims abstract description 19
- FKNQFGJONOIPTF-UHFFFAOYSA-N Sodium cation Chemical compound [Na+] FKNQFGJONOIPTF-UHFFFAOYSA-N 0.000 claims abstract description 18
- 150000002500 ions Chemical class 0.000 claims abstract description 4
- 239000000463 material Substances 0.000 claims description 23
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- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 15
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 14
- 239000012046 mixed solvent Substances 0.000 claims description 14
- 239000002243 precursor Substances 0.000 claims description 14
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 10
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- -1 transition metal salt Chemical class 0.000 claims description 10
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- 238000009792 diffusion process Methods 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 5
- KWSLGOVYXMQPPX-UHFFFAOYSA-N 5-[3-(trifluoromethyl)phenyl]-2h-tetrazole Chemical compound FC(F)(F)C1=CC=CC(C2=NNN=N2)=C1 KWSLGOVYXMQPPX-UHFFFAOYSA-N 0.000 claims description 4
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims description 4
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 claims description 4
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 125000000524 functional group Chemical group 0.000 claims description 4
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- 239000012299 nitrogen atmosphere Substances 0.000 claims description 4
- 229910001379 sodium hypophosphite Inorganic materials 0.000 claims description 4
- 230000009471 action Effects 0.000 claims description 3
- 239000001257 hydrogen Substances 0.000 claims description 3
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- 229910052750 molybdenum Inorganic materials 0.000 claims description 3
- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 3
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- 235000013855 polyvinylpyrrolidone Nutrition 0.000 claims description 3
- 239000001509 sodium citrate Substances 0.000 claims description 3
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 claims description 3
- 229910052720 vanadium Inorganic materials 0.000 claims description 3
- POILWHVDKZOXJZ-ARJAWSKDSA-M (z)-4-oxopent-2-en-2-olate Chemical compound C\C([O-])=C\C(C)=O POILWHVDKZOXJZ-ARJAWSKDSA-M 0.000 claims description 2
- CABMTIJINOIHOD-UHFFFAOYSA-N 2-[4-methyl-5-oxo-4-(propan-2-yl)-4,5-dihydro-1H-imidazol-2-yl]quinoline-3-carboxylic acid Chemical compound N1C(=O)C(C(C)C)(C)N=C1C1=NC2=CC=CC=C2C=C1C(O)=O CABMTIJINOIHOD-UHFFFAOYSA-N 0.000 claims description 2
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 claims description 2
- LZZYPRNAOMGNLH-UHFFFAOYSA-M Cetrimonium bromide Chemical compound [Br-].CCCCCCCCCCCCCCCC[N+](C)(C)C LZZYPRNAOMGNLH-UHFFFAOYSA-M 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 2
- WJJMNDUMQPNECX-UHFFFAOYSA-N Dipicolinic acid Natural products OC(=O)C1=CC=CC(C(O)=O)=N1 WJJMNDUMQPNECX-UHFFFAOYSA-N 0.000 claims description 2
- 229910002651 NO3 Inorganic materials 0.000 claims description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims description 2
- SIOXPEMLGUPBBT-UHFFFAOYSA-N Picolinic acid Natural products OC(=O)C1=CC=CC=N1 SIOXPEMLGUPBBT-UHFFFAOYSA-N 0.000 claims description 2
- DBMJMQXJHONAFJ-UHFFFAOYSA-M Sodium laurylsulphate Chemical compound [Na+].CCCCCCCCCCCCOS([O-])(=O)=O DBMJMQXJHONAFJ-UHFFFAOYSA-M 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 2
- KVNRLNFWIYMESJ-UHFFFAOYSA-N butyronitrile Chemical compound CCCC#N KVNRLNFWIYMESJ-UHFFFAOYSA-N 0.000 claims description 2
- QYQADNCHXSEGJT-UHFFFAOYSA-N cyclohexane-1,1-dicarboxylate;hydron Chemical compound OC(=O)C1(C(O)=O)CCCCC1 QYQADNCHXSEGJT-UHFFFAOYSA-N 0.000 claims description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 2
- 229910052742 iron Inorganic materials 0.000 claims description 2
- SKTCDJAMAYNROS-UHFFFAOYSA-N methoxycyclopentane Chemical compound COC1CCCC1 SKTCDJAMAYNROS-UHFFFAOYSA-N 0.000 claims description 2
- ABMFBCRYHDZLRD-UHFFFAOYSA-N naphthalene-1,4-dicarboxylic acid Chemical compound C1=CC=C2C(C(=O)O)=CC=C(C(O)=O)C2=C1 ABMFBCRYHDZLRD-UHFFFAOYSA-N 0.000 claims description 2
- 229920000371 poly(diallyldimethylammonium chloride) polymer Polymers 0.000 claims description 2
- 230000000630 rising effect Effects 0.000 claims description 2
- 235000011083 sodium citrates Nutrition 0.000 claims description 2
- 238000001179 sorption measurement Methods 0.000 claims description 2
- VXKWYPOMXBVZSJ-UHFFFAOYSA-N tetramethyltin Chemical compound C[Sn](C)(C)C VXKWYPOMXBVZSJ-UHFFFAOYSA-N 0.000 claims description 2
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- 230000005611 electricity Effects 0.000 abstract description 2
- 230000002035 prolonged effect Effects 0.000 abstract description 2
- 238000011065 in-situ storage Methods 0.000 abstract 1
- 239000002052 molecular layer Substances 0.000 abstract 1
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- 239000000243 solution Substances 0.000 description 25
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 7
- 229910052708 sodium Inorganic materials 0.000 description 7
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- 230000002441 reversible effect Effects 0.000 description 5
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- 239000007773 negative electrode material Substances 0.000 description 3
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 2
- DWAQJAXMDSEUJJ-UHFFFAOYSA-M Sodium bisulfite Chemical compound [Na+].OS([O-])=O DWAQJAXMDSEUJJ-UHFFFAOYSA-M 0.000 description 2
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- 230000004048 modification Effects 0.000 description 2
- 239000013099 nickel-based metal-organic framework Substances 0.000 description 2
- XNGIFLGASWRNHJ-UHFFFAOYSA-N phthalic acid Chemical compound OC(=O)C1=CC=CC=C1C(O)=O XNGIFLGASWRNHJ-UHFFFAOYSA-N 0.000 description 2
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- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
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- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- DPXJVFZANSGRMM-UHFFFAOYSA-N acetic acid;2,3,4,5,6-pentahydroxyhexanal;sodium Chemical compound [Na].CC(O)=O.OCC(O)C(O)C(O)C(O)C=O DPXJVFZANSGRMM-UHFFFAOYSA-N 0.000 description 1
- MQRWBMAEBQOWAF-UHFFFAOYSA-N acetic acid;nickel Chemical compound [Ni].CC(O)=O.CC(O)=O MQRWBMAEBQOWAF-UHFFFAOYSA-N 0.000 description 1
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- 238000000576 coating method Methods 0.000 description 1
- 229940011182 cobalt acetate Drugs 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- QAHREYKOYSIQPH-UHFFFAOYSA-L cobalt(II) acetate Chemical compound [Co+2].CC([O-])=O.CC([O-])=O QAHREYKOYSIQPH-UHFFFAOYSA-L 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000011889 copper foil Substances 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
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- BMGNSKKZFQMGDH-FDGPNNRMSA-L nickel(2+);(z)-4-oxopent-2-en-2-olate Chemical compound [Ni+2].C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O BMGNSKKZFQMGDH-FDGPNNRMSA-L 0.000 description 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Substances N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
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- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
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- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/08—Other phosphides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
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- C01B25/08—Other phosphides
- C01B25/088—Other phosphides containing plural metal
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
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Abstract
本发明公开一种过渡金属磷化物(TMPs)/C/MXene复合材料的制备方法，其通过离子静电互扩散技术，实现在MXene表面原位生长二维MOF纳米层，从而获得千层饼结构的MOF/MXene，最后通过磷化热处理得到TMPs/C/MXene复合材料。本发明中，二维MOFs层覆盖在纳米MXene表面或嵌入MXene层间，磷化后实现了TMPs与MXene的高效传质传电，保证了复合材料结构稳定，延长了钠离子电池使用寿命。
Description
技术领域
本发明属于材料合成及能源技术领域，具体涉及一种千层饼结构的过渡金属磷化物/C/MXene复合材料的制备方法。
背景技术
由于钠资源丰富且分布广泛，因此钠离子电池的预期生产成本较锂离子电池更低。目前钠离子电池仍处于前期发展阶段，其结构组成与锂离子电池相似，但负极材料无法使用锂电所用的石墨。因此，探索高性能的负极材料是钠离子电池发展的重要课题。过渡金属磷化物(TMPs)具有超高的可逆容量、不错的电子传递率和倍率性能等优点，是值得深入研究的新型钠离子电池负极材料。但是此类材料储能过程会出现明显的体积膨胀，且倍率性能较低，上述问题限制了过渡金属磷化物作为负极材料的应用。
发明内容
本发明的主要目的在于克服现有技术的不足，提供一种钠离子电池用TMPs/C/MXene复合负极材料制备方法。
为实现上述目的，本发明提供的一种用于钠离子电池的TMPs/C/MXene复合负极材料的制备方法，包括以下步骤：
(1)将有机配体溶于有机混合溶剂中得到溶液A；
将分层MXene和活性剂加入有机混合溶剂得到溶液B；
将过渡金属盐溶解于有机混合溶剂中得到溶液C；
其中，所述有机配体含有羟基和/或-O的官能团，使其能在氢键作用下锚定在MXene表面；
在试管底部加入溶液A，再加入一定量的溶液B于试管中层，最后缓慢加入溶液C于试管上层；
将装有分层溶液的试管置于10～90℃恒温环境中，利用离子静电吸附和互扩散作用，静置反应2～24小时，待分层消失后，获得二维MOFs层覆盖在纳米MXene表面和/或二维MOFs层嵌入MXene层间的前驱体；
(2)在氮气气氛下，将MOF/MXene前驱体与次亚磷酸氢钠混合煅烧，煅烧温度200～400℃，即可得到用于钠离子电池的千层饼结构的过渡金属磷化物/C/MXene复合负极材料。
优选地，步骤(1)中所述有机配体包括对苯二甲酸、均苯三甲酸、环己烷二甲酸、1,4-萘二甲酸、2,6-吡啶二羧酸、2-吡啶甲酸中的一种或多种。
优选地，步骤(1)中所述有机混合溶剂由乙醇、甲醇、乙腈、丁腈、苯、DMF、二甲基甲酰胺、正己烷、丙酮、二甲基亚砜、环戊基甲醚中的至少两种组成，溶液A与溶液B的体积比是1：(0.1～1)，溶液A与溶液C的体积比是1：(0.5～5)。
优选地，步骤(1)中所述活性剂包括十二烷基硫酸钠、十六烷基三甲基溴化铵、F127、聚二烯丙基二甲基氯化铵、柠檬酸钠、聚乙烯吡咯烷酮中的一种或多种。
优选地，步骤(1)中过渡金属盐包括Fe、Ni、Co、Zn、Mn、Cu几种元素的硝酸盐、氯化盐、硫酸盐、乙酰丙酮盐、醋酸盐中的一种或几种，过渡金属盐与有机配体的质量比为1:(0.1～10)，过渡金属盐与活性剂的质量比为1:(0.5～50)。
优选地，步骤(1)中所用的MXene材料包括少层结构的Ti3C2、Ti2C、Nb2C、V2C、Mo2C中的一种或多种，过渡金属盐与MXene材料的质量比是1:(0.005～1)。
优选地，步骤(2)中前驱体与次亚磷酸氢钠的质量比为1：(5～20)，煅烧条件为：升温速率1～10℃/min，煅烧时间为1～5h。
优选地，步骤(1)中得到的二维MOFs层的厚度为20～150nm，MOFs与MXene的堆叠层数为2～10层，前驱体厚度为50～800nm。
优选地，步骤(2)中得到的过渡金属磷化物/C/MXene复合负极材料厚度为50～800nm，碳含量为5～30wt.％，比表面积为50～400m2/g，孔洞直径为5～50nm。
优选地，步骤(2)中得到的过渡金属磷化物/C/MXene复合负极材料中过渡金属磷化物/C层厚度为20～150nm，过渡金属磷化物/C与MXene的堆叠层数为2～10层。
本发明的发明构思如下：
TMPs通过转化反应储存钠离子，具有较高的理论容量和较低的氧化还原电位，但TMPs的应用受限于循环稳定性差和倍率性能欠佳等问题。二维(2D)纳米材料能够提供较短的离子扩散路径和开放的电荷传输通道，有利于快速充放电，较高的比表面积使其表现出不错的赝电容性能，超薄的结构也能够有效缓解储钠膨胀效应。MXene是一类新型二维材料，由MAX相材料经HF(或LiF与浓HCl的混合溶液)等刻蚀剥离所得，经刻蚀的MXene材料带有-OH、-O、-F等表面官能团，典型的有Ti3C2、Ti2C、Nb2C、V2C、Mo2C等，刻蚀后的上层液可以收获分层的MXene材料。其用作钠离子电池负极材料时，具有导电性能好、钠离子扩散效率高的优点。但MXene片层的塌陷和再堆垛会降低导电率并限制电解液的浸润，阻碍MXene的活性位点的充分利用。在本发明中，将高比容量的金属磷化物与高导电性的MXene材料复合，将两种材料优势互补，获得高性能的钠离子电池负极材料。
针对过渡金属磷化物和MXene存在的储钠的缺点，本发明通过离子静电及互扩散作用，在MXene表面缓慢形成超薄二维MOFs(金属-有机框架材料)层。利用配体与MXene官能团形成氢键，实现MOF模板与MXene的自组装，在反应条件及活性剂的作用下，调节MOF/MXene的形貌和结构，最后通过磷化热处理得到球形TMPs/C/MXene复合材料。TMPs/C/MXene复合材料中，MXene具有一定的韧性，能够起到保护和桥连作用，从而增强了TMPs的电化学性能；TMPs则覆盖在MXene表面，避免了塌陷和再堆垛出现。
本发明所采用的技术方案与现有技术相比具有下列优点：
1、本发明设计了超薄纳米TMPs/C材料与MXene纳米片交替堆叠的千层饼结构，缓解磷化物储钠过程的体积膨胀，从而延长电池寿命。
2、超薄纳米TMPs/C层能够扩大MXene的层间距，避免MXene再堆叠等问题，从而提高复合材料的储钠容量。
3、MXene材料能够起到稳固和桥连TMPs/C纳米层的作用，减少磷化物与电解液间的副反应并增强电子的传输速度的作用，改进材料倍率性能，提高材料储钠稳定性。
3、本发明制备的TMPs/C/MXene复合负极材料具有较强的循环性能，在200mA/g的高电流密度下循环200周可逆容量可达350mAh/g以上。
附图说明
图1为实施例1中CoNiP/C/MXene复合负极材料的合成示意图。
图2为实施例1中CoNiP/C/MXene复合负极材料在200mA/g电流密度下的循环性能图。
具体实施方式
为了更好的理解本发明，下面通过具体实施方式对本发明进一步描述，但所列举的实施例并不限制本发明的保护范围。
实施例1
一种用于钠离子电池的TMPs/C/MXene复合负极材料的制备方法，具体步骤如下：
(1)将100mg对苯二甲酸溶于20ml甲醇和DMF的混合溶剂中得到溶液A；将200mg聚乙烯吡咯烷酮和5mg分层Ti3C2加入到15ml甲醇和DMF的混合溶剂中得到溶液B；将10mg醋酸钴和10mg醋酸镍溶解于20ml甲醇和DMF的混合溶剂中得到溶液C。在试管底部加入溶液A，再加入溶液B于试管中层，最后缓慢加入溶液C于试管上层。将装有分层溶液的试管置于60℃恒温环境中，静置反应12小时，待分层消失后，获得CoNi-MOF/Ti3C2前驱体。CoNi-MOF厚度约为40nm，MOFs与MXene的堆叠层数为4～8层，前驱体厚度为200～500nm。
(2)在氮气气氛下将30mg前驱体与160mg次亚磷酸氢钠混合煅烧，升温速率5℃/min，煅烧温度320℃，煅烧时间为3h，即可得到用于钠离子电池的千层饼结构的CoNiP/C/MXene复合负极材料。CoNiP/C/MXene复合材料厚度为160～480nm，碳含量为10wt.％，比表面积为341m2/g，孔洞直径为5～30nm。其中CoNiP/C层厚度约为36nm，CoNiP/C与MXene的堆叠层数为4～8层。
本实施例制备CoNiP/C/MXene材料的合成示意图如图1所示。
电化学性能测试：将所制得的电极材料复合材料与乙炔黑和羧甲基纤维素钠(CMC)按质量比8∶1∶1混合均匀，加入适量去离子水调至浆料，将浆料涂膜在铜箔上制得电极。此试验电极在真空烘箱中110℃干燥24h，再在高纯氩气氛手套箱中封装电池，电解液为NaPF6溶解于EC：DEC(体积比1：1)的混合液，以玻璃纤维滤纸为隔膜，金属钠为电池负极组装成CR2016型扣式电池。放充电条件：以相同的电流密度放电到0.02V后再充电到3V，选择的电流密度为200mA/g。对上述电池进行测试，测试结果如图2，循环200周后电极可逆容量保持在395.6mAh/g，说明CoNiP/C/MXene材料具有较好的容量保持率和循环稳定性。
实施例2
一种用于钠离子电池的TMPs/C/MXene复合负极材料的制备方法，具体步骤如下：
(1)将100mg均苯三甲酸溶于30ml乙腈、丙酮和DMF的混合溶剂中得到溶液A；将250mg柠檬酸钠和10mg分层Ti2C加入到20ml乙腈、丙酮和DMF的混合溶剂中得到溶液B；将30mg乙酰丙酮镍溶解于60ml乙腈、丙酮和DMF的混合溶剂中得到溶液C。在试管底部加入溶液A，再加入溶液B于试管中层，最后缓慢加入溶液C于试管上层。将装有分层溶液的试管置于80℃恒温环境中，静置反应18小时，待分层消失后，获得Ni-MOF/Ti3C2前驱体。Ni-MOF厚度约为50nm，MOFs与MXene的堆叠层数为2～7层，前驱体厚度为100～300nm。
(2)在氮气气氛下将30mg前驱体与500mg次亚磷酸氢钠混合煅烧，升温速率3℃/min，煅烧温度280℃，煅烧时间为5h，即可得到用于钠离子电池的千层饼结构的NiP/C/MXene复合负极材料。NiP/C/MXene复合材料厚度为120～390nm，碳含量为15wt.％，比表面积为312m2/g，孔洞直径为5～50nm。其中NiP/C层厚度约为36nm，NiP/C与MXene的堆叠层数为2～7层。
电化学性能测试：本实施例的电化学测试与实施例1相同，可逆容量保持在360.2mAh/g，说明NiP-C/MXene材料具有较好的容量保持率和循环稳定性
对比例
熔炼法制备钠离子电池用CoNiP材料，具体步骤如下：
(1)称取3g的钴粉、2.5g的镍粉、8g红磷，混合后倒入坩埚内。
(2)对步骤(1)坩埚进行煅烧处理。煅烧气氛为氮气，煅烧温度700℃，时间8h，待炉冷却得到CoNiP材料，研磨过400目筛。
电化学性能测试：本对比例的电化学性能测试与实施例1相同，CoNiP材料在200mA/g电流密度下循环200周的可逆容量为38.6mAh/g。
以上所述仅为本发明的优选实施例而已，并不用于限制本发明，对于本领域的技术人员来说，本发明可以有各种更改和变化。凡在本发明的精神和原则之内所作的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。
Claims (10)
1.一种过渡金属磷化物/C/MXene复合材料的制备方法，其特征在于，包括以下步骤：
(1)将有机配体溶于有机混合溶剂中得到溶液A；
将分层MXene和活性剂加入有机混合溶剂得到溶液B；
将过渡金属盐溶解于有机混合溶剂中得到溶液C；
其中，所述有机配体含有羟基和/或-O的官能团，使其能在氢键作用下锚定在MXene表面；
在试管底部加入溶液A，再加入一定量的溶液B于试管中层，最后缓慢加入溶液C于试管上层；
将装有分层溶液的试管置于10～90℃恒温环境中，利用离子静电吸附和互扩散作用，静置反应2～24小时，待分层消失后，获得二维MOFs层覆盖在纳米MXene表面和/或二维MOFs层嵌入MXene层间的前驱体；
(2)在氮气气氛下，将MOF/MXene前驱体与次亚磷酸氢钠混合煅烧，煅烧温度200～400℃，即可得到用于钠离子电池的千层饼结构的过渡金属磷化物/C/MXene复合负极材料。
2.如权利要求1所述的制备方法，其特征在于，步骤(1)中所述有机配体包括对苯二甲酸、均苯三甲酸、环己烷二甲酸、1,4-萘二甲酸、2,6-吡啶二羧酸、2-吡啶甲酸中的一种或多种。
3.如权利要求1所述的制备方法，其特征在于，步骤(1)中所述有机混合溶剂由乙醇、甲醇、乙腈、丁腈、苯、DMF、二甲基甲酰胺、正己烷、丙酮、二甲基亚砜、环戊基甲醚中的至少两种组成，溶液A与溶液B的体积比是1：(0.1～1)，溶液A与溶液C的体积比是1：(0.5～5)。
4.如权利要求1所述的制备方法，其特征在于，步骤(1)中所述活性剂包括十二烷基硫酸钠、十六烷基三甲基溴化铵、F127、聚二烯丙基二甲基氯化铵、柠檬酸钠、聚乙烯吡咯烷酮中的一种或多种。
5.如权利要求1所述的制备方法，其特征在于，步骤(1)中过渡金属盐包括Fe、Ni、Co、Zn、Mn、Cu几种元素的硝酸盐、氯化盐、硫酸盐、乙酰丙酮盐、醋酸盐中的一种或几种，过渡金属盐与有机配体的质量比为1:(0.1～10)，过渡金属盐与活性剂的质量比为1:(0.5～50)。
6.如权利要求1所述的制备方法，其特征在于，步骤(1)中所用的MXene材料包括少层结构的Ti3C2、Ti2C、Nb2C、V2C、Mo2C中的一种或多种，过渡金属盐与MXene材料的质量比是1:(0.005～1)。
7.如权利要求1所述的制备方法，其特征在于，步骤(2)中前驱体与次亚磷酸氢钠的质量比为1：(5～20)，煅烧条件为：升温速率1～10℃/min，煅烧时间为1～5h。
8.如权利要求1所述的制备方法，其特征在于，步骤(1)中得到的二维MOFs层的厚度为20～150nm，MOFs与MXene的堆叠层数为2～10层，前驱体厚度为50～800nm。
9.如权利要求1所述的制备方法，其特征在于，步骤(2)中得到的过渡金属磷化物/C/MXene复合负极材料厚度为50～800nm，碳含量为5～30wt.％，比表面积为50～400m2/g，孔洞直径为5～50nm。
10.如权利要求1所述的制备方法，其特征在于，步骤(2)中得到的过渡金属磷化物/C/MXene复合负极材料中过渡金属磷化物/C层厚度为20～150nm，过渡金属磷化物/C与MXene的堆叠层数为2～10层。
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| CN118005947A (zh) * | 2024-04-08 | 2024-05-10 | 德州学院 | 一种双稠环配体mof晶体材料及其制备方法和在分离苯/环己烷的应用 |
| CN118005947B (zh) * | 2024-04-08 | 2024-06-07 | 德州学院 | 一种双稠环配体mof晶体材料及其制备方法和在分离苯/环己烷的应用 |
| CN118588932A (zh) * | 2024-08-06 | 2024-09-03 | 中国海洋大学三亚海洋研究院 | 一种用于高比容量锂离子电池电极材料的制备方法 |
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