University of Chinese Academy of Sciences , Beijing 100049, China.
School of Environment, Tsinghua University , Beijing 100084, China.
ACS Appl Mater Interfaces. 2018 Jan 24;10(3):2451-2459. doi: 10.1021/acsami.7b14733. Epub 2018 Jan 11.
Phase tuning during crystal phase transformation is an important but challenging step toward the development of effective hydrogen evolution reaction (HER) catalysts. Herein, we report on a feasible approach to achieve effective polycrystalline molybdenum carbides during transformation from α-phase to β-phase through the regulation of additive (tungsten) amount. Benefiting from the optimal Mo-C bond lengths and abundant active sites, molybdenum carbide prepared with a moderate addition of tungsten enhanced electrocatalytic activity and stability compared with pure α-phase and β-phase MoC in the HER, and only required an overpotential of 148 and 93 mV to drive 20 mA cm of current density in 0.5 M HSO and 1.0 M KOH, respectively.
在晶体相转变过程中进行相调谐是开发有效析氢反应（HER）催化剂的重要但具有挑战性的步骤。在此，我们报告了一种可行的方法，通过调节添加剂（钨）的量，使α相到β相转变过程中实现有效的多晶碳化钼。受益于最佳的 Mo-C 键长和丰富的活性位，与纯 α 相和 β 相 MoC 相比，适量添加钨的碳化钼在 HER 中增强了电催化活性和稳定性，在 0.5 M HSO 和 1.0 M KOH 中分别仅需 148 和 93 mV 的过电势即可驱动 20 mA cm 的电流密度。
