Single-Layer Cu2WS4 with Promising Electrocatalytic Activity towards Hydrogen Evolution Reaction.
Single-Layer Cu2WS4 with Promising Electrocatalytic Activity towards Hydrogen Evolution Reaction.
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DOI：
10.1021/acsami.9b18065
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发表时间：
2019-11
影响因子：
9.5
通讯作者：
Qian Wu;Yandong Ma;Rui Peng;Baibiao Huang;Ying Dai
中科院分区：
文献类型：
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作者：
Qian Wu;Yandong Ma;Rui Peng;Baibiao Huang;Ying Dai
二维析氢反应（HER）电催化剂因其良好的材料性能而成为高成本铂的理想替代品。然而，现有的少数二维HER电催化剂存在限制其性能的缺点。在这里，我们报告了单层A2BS4 （a =Ag, Cu； B= Mo， W）作为HER电催化剂的第一性原理研究，并确定单层Cu2WS4是有希望的候选材料。发现单层A2BS4具有化学、动态和热稳定性。它们只需要很小的能量成本就能从它们的分层体中产生，这表明它们在实验中有可能脱落。最重要的是，在没有明显空位密度和大应变的情况下，单层Cu2WS4基面对HER表现出优异的电催化活性。这种活性归因于引入的隙内态和吸附氢时d带中心的移动。这些特性表明单层Cu2WS4是一种非凡的二维HER电催化剂。
Two-dimensional hydrogen evolution reaction (HER) electrocatalysts are outstanding alternatives to high-cost Pt due to their good material properties. However, the few existing two-dimensional HER electrocatalysts have shortcomings that restrict their performance. Here, we report a first-principles study of single-layer A2BS4 (A=Ag, Cu; B= Mo, W) as HER electrocatalysts, and identify single-layer Cu2WS4 as a promising candidate. Single-layer A2BS4 are found to be chemically, dynamically and thermally stable. They require only a small energetic cost to be created from their layered bulks, suggesting the possibility of their exfoliation in experiments. Most importantly, without significant density of vacancies and in the absence of large applied strain, the basal plane of single-layer Cu2WS4 shows excellent electrocatalytic activity toward HER. Such activity is attributed to the introduced in-gap states and d band center shifting upon adsorbing hydrogen. These characteristics suggest that single-layer Cu2WS4 is an extraordinary two-dimensional HER electrocatalyst.