One-step synthesis of Co-doped 1T-MoS2 nanosheets with efficient and stable HER activity in alkaline solutions
One-step synthesis of Co-doped 1T-MoS2 nanosheets with efficient and stable HER activity in alkaline solutions
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一步合成在碱性溶液中具有高效稳定 HER 活性的钴掺杂 1T-MoS2 纳米片
DOI：
10.1016/j.matchemphys.2020.122642
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发表时间：
2020-04-01
影响因子：
4.6
通讯作者：
Huang, Baibiao
中科院分区：
文献类型：
--
作者：
Ma, Fahao;Liang, Yan;Huang, Baibiao
二硫化钼 (1T-MoS2) 的金属相在酸性溶液中显示出析氢反应 (HER) 的巨大潜力。然而，目前很少有研究报道如何增强1T-oS(2)在碱性溶液中的固有催化活性，使其更适合大规模应用中的水分解。在这里，我们报告了一种合成钴掺杂 1T-MoS2 纳米片的水热工艺。钴掺杂的1T-MoS2在1 M KOH水溶液中在10 mA cm(-2)下表现出240 mV的过电势和68 mV dec(-1)的小塔菲尔斜率，这比原始的1T-MoS2好得多，甚至优于在酸性溶液中运行的其他MoS2基催化剂。此外，钴掺杂1T-MoS2纳米片表现出较高的稳定性，在水中保存1个月后仍保持金属相。基于密度泛函理论的计算表明，Co 掺杂不会将原始 1T-MoS2 转变为其半导体对应物。此外，初始水解离步骤的能量势垒的降低是促进 HER 过程的原因。
The metallic phase of molybdenum disulfide (1T-MoS2) shows great potential for hydrogen evolution reaction (HER) in acid solutions. However, few works have been reported to enhance the intrinsic catalytic activity of 1T-oS(2) in basic solutions, which is more applicable for water splitting in large-scale applications. Here, we report a hydrothermal process for synthesizing cobalt-doped 1T-MoS2 nanosheets. The cobalt-doped 1T-MoS2 exhibits an overpotential of 240 mV at 10 mA cm(-2) in 1 M KOH aqueous solutions and a small Tafel slope of 68 mV dec(-1), which is much better than that of the pristine 1T-MoS2 and even superior to other MoS2-based catalysts operated in acid solutions. Moreover, the cobalt-doped 1T-MoS2 nanosheets show high stability, and remain metallic phase after being reserved in water for one month. Calculations based on density functional theory reveal that Co doping does not transform the pristine 1T-MoS2 into its semiconducting counterpart. In addition, the reduction of energy barrier of the initial water dissociation step is responsible for the facilitated HER process.