单原子改性二硫化钼电催化析氢

Single-Atom-Modified MoS;for Efficient Hydrogen Evolution

氢能是21世纪最理想的清洁能源之一。相比于天然气和煤炭制氢,电解水制氢具有成本低、效率高、无污染、原料丰富的特点,可以有效缓解CO;过量排放导致的温室效应。电催化析氢需要活性高、稳定性好、廉价易得的催化剂克服反应能垒并加速动力学过程,对实现分解水制氢的规模化应用具有重要的推动作用。铂基催化剂被公认为性能最优异的析氢电催化剂之一,但由于丰度低、成本高,不适用于大规模产氢。二硫化钼(MoS;)作为典型的二维材料之一,因其高活性位点暴露和高比表面积在析氢领域展现出一定的应用潜能,并有望取代铂基催化剂。本文基于MoS;电催化剂在析氢领域的研究现状,对单原子掺杂改性MoS;以提高其催化活性的研究进行了综述,以析氢过电位(Overpotential)及塔菲尔(Tafel)曲线斜率为依据,总结了贵金属单原子、非贵金属单原子及非金属单原子改性MoS;催化剂的结构与性能以及它们之间的构效关系,在此基础上,提出MoS;析氢催化剂目前存在的科学问题并指出了未来的努力方向。

The over-reliance on fossil fuels leads to deteriorating ecological environment and motivates us to develop sustainable and clean energy alternatives in order for our long-term survival on the earth.Hydrogen energy is one of the most promising energy carriers in the 21;century since the only by-product is H;O.In comparison to steam reforming of natural gas and coal,hydrogen evolution reaction(HER)via H;O electrolysis is a more attracting pathway for H;production because of the low cost,high efficiency and abundant raw materials,which would contribute to a lower carbon footprint.HER requires stable and active enough catalyst materials to overcome the reaction barriers.It is well known that Pt group materials are state-of-the-art HER catalysts,but unfortunately,the low abundance and high cost complicate its large-scale applications.The transition metal disulfides(TMDs)possess a two-dimensional layered structure and a larger specific surface area,which is conducive to expose more active sites.In particular,MoS;,a representative of TMDs,has attracted tremendous research interests in HER domain and is supposed to be a cost-affordable alternative to Pt-based catalysts.In this work,the research status of MoS;modified by single atoms(SA-MoS;)of noble metal,non-noble metal,and nonmetal,to catalyze HER reactions is reviewed.Based on the overpotential and Tafel slope,the structure-function relationship between HER performance and SA-MoS;structures is summarized.Finally,future research directions are proposed and hopefully,this paper will guide rational design of SA-MoS;for a more efficient HER electrocatalyst.