过渡金属硫属化合物富缺陷多孔超薄纳米片的等离子体合成与电催化析氢性能

Non-layered structured transition metal chalcogenides are the excellent candidates as efficient electrocatalysts for the hydrogen evolution reaction. Porous or ultrathin structure could be found to further increase their atomic utilization and thus improve the mass activity. The vacancies in electrocatalysts could improve the catalysis performance by enhancing water adsorption/dissociation and optimizing the electronic properties. However, the development of one accurate and controllable method to synthesize non-layered structured nanosheets about transition metal chalcogenides with defect-rich, porous and ultrathin features is still a big challenge in a variety of fields including inorganic synthesis chemistry, nanochemistry and hydrogen energy chemistry. Here, we propose a facile and general strategy to prepare non-layered structured, defect-rich, ultrathin and porous nanosheets through plasma treatment of lamellar inorganic-organic hybrid precursors, in which few-atom-thickness inorganic layer and organic layer alternately arrange. The plasma-induced cleaning of organic layer results in the synthesis of inorganic ultrathin nanosheets with clean surfaces. The etching and reducing functions of plasma lead to the formation of pores and vacancies in as-converted products, respectively. Firstly, we can precisely control the composition, thickness and defect concentration in the as-prepared products by adjusting the type and proportion of metal elements in the precursors as well as the treatment conditions. Secondly, the ideal catalyst model for in-situ characterization can be screened through this strategy. Thirdly, combining various characterizations with theoretical simulation, the evolving rule for surface structure and vacancies in the process of hydrogen evolution reaction will be revealed. Finally, the dependence of electronic structures on defect concentration and multi-metal interactions, and their structure-function relationships on electrocatalytic performance will be explored. It is expected that our work will provide scientific proof for both the accurate synthesis of novel porous two-dimensional nanomaterials and the search of efficient hydrogen evolving electrocatalysts.

非层状结构的过渡金属硫属化合物材料是性能优异的水分解析氢电催化剂，多孔或超薄结构可增加其原子利用率。缺陷能增强水的吸附，调控电子结构，从而改进性能。然而，富缺陷多孔超薄材料的精准合成仍是无机合成化学、纳米化学和氢能源化学领域的重要挑战之一。.本项目拟选择无机有机层交替排列的过渡金属基无机有机杂化物作为前驱物，利用等离子体技术中的清洁功能去除杂化材料的有机层来制备表面干净的无机超薄二维材料，利用刻蚀作用和还原作用产生孔与缺陷，实现富缺陷超薄多孔纳米片的普适合成。通过控制前驱物的金属元素种类及比例、等离子体合成条件等来实现产物的组成、厚度和缺陷浓度的精准调控，筛选出理想的原位研究模型。结合理论模拟与多种表征手段，揭示了材料缺陷浓度和表面结构在电催化过程中的演化规律，阐明阴离子缺陷、多金属间相互作用对电子结构与催化析氢活性间的构效关系，为二维多孔新材料的精准合成与高效制氢材料的探索提供科学依据。

非层状结构的过渡金属硫属化合物材料是性能优异的水分解析氢电催化剂，而富缺陷多孔超薄过渡金属硫属化合物的精准合成也是无机合成化学、纳米化学和氢能源化学领域的重要挑战之一。基于此，在国家自然科学基金的资助下，创新和发展了无机有机杂化材料的离子交换与组分剥离策略，实现了富阴离子缺陷超薄多孔过渡金属硫属化合物的精准合成，并将其用于高效析氢和硝基转移氢化。系统研究了富阴离子缺陷过渡金属硫属化合物中阴离子缺陷在析氢过程中所发生的结构演化以及真正的活性起源。此外，还对电解水产生的活性氢进行原位利用，通过利用电化学原位重构形成的金属催化剂，以水为氢源，实现了有机物水相氢化、硝酸根还原氢化和CO2还原氢化。结合常规表征以及原位光谱技术和原位X射线衍射技术，明确了材料在工况条件下的活性物种，揭示了反应的活性物种以及反应中间体在催化剂表面的吸附方式，明确了材料的结构与电催化性能间的构效关系，为理解金属硫属化合物的原位结构演化及新型高效电催化剂的设计与精准合成提供了科学基础。相关工作已发表在Chem. Soc. Rev.、Natl. Sci. Rev.（2篇）、J. Am. Chem. Soc.（3篇）、Chem（2篇）、Angew. Chem. Int. Ed.（11篇）、Sci. Adv.、Nat. Commun.（4篇）等期刊上。2篇论文入选J. Am. Chem. Soc.的外封面，2篇论文入选Angew. Chem. Int. Ed.热点论文，10篇论文入选ESI高被引论文。收到Chem. Soc. Rev.等期刊的约稿。项目负责人担任中国化学会晶体化学专业委员会委员、青年化学工作者委员会委员及Sci. China Chem.编委等，获得了Young Innovator Award in Nano Research (Nanocatalysis)、National Science Review年度优秀论文 （2022）、Science China Chemistry年度优秀论文（2022）等荣誉。在本项目的资助下，项目负责人入选教育部“长江学者”特聘教授（2022-2026）、英国皇家化学会会士（2019）和“科睿唯安”全球高被引科学家（化学，2021-2022），培养了包括1名中国博新计划入选者在内的10名博士生，15名硕士生和3名博士后。