Nitrogen-Doped Cobalt Diselenide with Cubic Phase Maintained for Enhanced Alkaline Hydrogen Evolution
Nitrogen-Doped Cobalt Diselenide with Cubic Phase Maintained for Enhanced Alkaline Hydrogen Evolution
复制标题
维持立方相的氮掺杂二硒化钴可增强碱性析氢
DOI：
10.1002/anie.202109116
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发表时间：
2021-08-21
影响因子：
16.6
通讯作者：
Xie, Yi
中科院分区：
文献类型：
--
作者：
Sun, Yiqiang;Li, Xiuling;Xie, Yi
杂原子的引入是调节电催化剂本征电子结构以提高其催化活性的重要途径之一。然而，对于具有高度对称晶体结构的过渡金属硫族化合物（HS-TMC），杂原子的引入，特别是大原子半径的杂原子的引入，往往会引起较大的晶格畸变和空位缺陷，从而可能导致掺杂材料的结构相变或催化反应过程中的结构相重构。这种不可预测的情况将使得难以探索掺杂催化剂的本征电子结构与催化活性之间的联系。本文以结晶稳定的立方CoSe 2相为例，证明了氮的引入可以有效地调节HS-TMC的本征电子结构，使其具有结构相稳定性，从而提高其析氢活性（HER）的电催化活性。相比之下，磷的引入可以导致从立方相CoSe 2到正交相的结构相变，并且磷掺杂的CoSe 2的结构相对于HER是不稳定的。
The introduction of heteroatoms is one of the most important ways to modulate the intrinsic electronic structure of electrocatalysts to improve their catalytic activity. However, for transition metal chalcogenides with highly symmetric crystal structure (HS-TMC), the introduction of heteroatoms, especially those with large atomic radius, often induces large lattice distortion and vacancy defects, which may lead to structural phase transition of doped materials or structural phase reconstruction during the catalytic reaction. Such unpredictable situations will make it difficult to explore the connection between the intrinsic electronic structure of doped catalysts and catalytic activity. Herein, taking thermodynamically stable cubic CoSe2 phase as an example, we demonstrate that nitrogen incorporation can effectively regulate the intrinsic electronic structure of HS-TMC with structural phase stability and thus promote its electrocatalytic activity for the hydrogen evolution activity (HER). In contrast, the introduction of phosphorus can lead to structural phase transition from cubic CoSe2 to orthorhombic phase, and the structural phase of phosphorus-doped CoSe2 is unstable for HER.