Non-precious metal-based electrocatalyst with high activity and stability for efficient hydrogen evolution reaction (HER) is of critical importance toward low-cost and large-scale water splitting. Traditional MoS2 has electrocatalytic hydrogen evolution inertness in alkaline environment, which is detrimental to the adsorption and dissociation of water. Composited with electrocatalyst with good electrical conductivity can enhance its HER activity. In this work, we for the first time construct a carbon-supported hollow heterostructure MoS2@Mo2C composite via two-step calcination and sulfurized process from carbonized Mo2C–Mo3C2 heteronanowires. The results show that the existence of the Mo3C2 phase is the key point to construct the effective heterostructure with hollow morphology. Due to the strong negative hydrogen binding energy for H on surface of Mo2C, the H+ reduction in the MoS2@Mo2C in the Volmer step can be enhanced. Compared with MoS2, MoS2@Mo2C has high electrocatalytic activity for hydrogen evolution with an onset potential of 28 mV, overpotential of 129 mV at the current density of 10 mA cm−2, a small Tafel slope of 78 mV dec−1, and an excellent stability. This work will provide new insights into the design of high-efficiency HER catalysts via interfacial engineering at nanoscale for commercial water splitting.

中文翻译：

---

MoS2@Mo2C在氮掺杂碳上的结构设计用于增强碱性析氢反应

具有高效析氢反应（HER）活性和稳定性的非贵金属基电催化剂对于低成本和大规模水分解至关重要。传统的MoS2在碱​​性环境下具有电催化析氢惰性，不利于水的吸附和解离。与具有良好导电性的电催化剂复合可增强其HER活性。在这项工作中，我们首次通过碳化的 Mo2C–Mo3C2 异质纳米线通过两步煅烧和硫化工艺构建了碳负载的空心异质结构 MoS2@Mo2C 复合材料。结果表明，Mo3C2相的存在是构建具有空心形貌的有效异质结构的关键。由于 Mo2C 表面 H 具有很强的负氢结合能，因此可以增强 Volmer 步骤中 MoS2@Mo2C 中 H+ 的还原。与 MoS2 相比，MoS2@Mo2C 具有较高的析氢电催化活性，起始电位为 28 mV，10 mA cm−2 电流密度下的过电位为 129 mV，Tafel 斜率为 78 mV dec−1，以及优异的稳定性。这项工作将为通过纳米级界面工程设计用于商业水分解的高效 HER 催化剂提供新的见解。和出色的稳定性。这项工作将为通过纳米级界面工程设计用于商业水分解的高效 HER 催化剂提供新的见解。和出色的稳定性。这项工作将为通过纳米级界面工程设计用于商业水分解的高效 HER 催化剂提供新的见解。