Li Jing, Zhou Chenmin, Mu Jianshuai, Yang En-Cui, Zhao Xiao-Jun
College of Chemistry, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University Tianjin 300387 P. R. China
Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300071 China.
RSC Adv. 2018 May 10;8(31):17202-17208. doi: 10.1039/c8ra02020e. eCollection 2018 May 9.
The development of non-precious metal based electrocatalysts for the hydrogen evolution reaction (HER) has received more and more attention over recent years owing to energy and environmental issues, and Mo based materials have been explored as a promising candidate. In this work, molybdenum carbide/N-doped carbon hybrids (MoC@NC) were synthesized facilely one-step high-temperature pyrolysis by adjusting the mass ratio of urea and ammonium molybdate. The MoC@NC consisted of ultrasmall nanoparticles encapsulated by N-doped carbon, which had high specific surface area. They all exhibited efficient HER activity, and the MoC@NC with a mass ratio of 160 (MoC@NC-160) showed the best HER activity, with a low overpotential of 90 mV to reach 10 mA cm and a small Tafel slope of 50 mV dec, which was one of the most active reported MoC-based electrocatalysts. The excellent HER activity of MoC@NC-160 was attributed to the following features: (1) the highly dispersed ultrasmall MoC nanoparticles, which exhibited high electrochemically active surface areas; (2) the synergistic effect of the N-doped carbon shell/matrix, which facilitated the electron transport.
近年来，由于能源和环境问题，用于析氢反应（HER）的非贵金属基电催化剂的开发受到了越来越多的关注，钼基材料已被探索为一种有前途的候选材料。在这项工作中，通过调节尿素和钼酸铵的质量比，采用一步高温热解法轻松合成了碳化钼/N掺杂碳杂化材料（MoC@NC）。MoC@NC由被N掺杂碳包裹的超小纳米颗粒组成，具有高比表面积。它们均表现出高效的析氢反应活性，质量比为160的MoC@NC（MoC@NC-160）表现出最佳的析氢反应活性，达到10 mA cm时过电位低至90 mV，塔菲尔斜率小至50 mV dec，是已报道的最具活性的碳化钼基电催化剂之一。MoC@NC-160优异的析氢反应活性归因于以下特点：（1）高度分散的超小碳化钼纳米颗粒，具有高电化学活性表面积；（2）N掺杂碳壳/基体的协同效应，促进了电子传输。
