Chen Zhigang, Yang Minghao, Li Yifan, Gong Wenbin, Wang Juan, Liu Tong, Zhang Chunyu, Hou Shuang, Yang Guang, Li Hao, Jin Ye, Zhang Chunyan, Tian Zhongqing, Meng Fancheng, Cui Yi
School of Materials Science and Engineering, Chongqing University of Technology, Chongqing, China.
i-lab, Vacuum Interconnected Nanotech Workstation (Nano-X), Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, China.
Nat Commun. 2025 Jan 6;16(1):418. doi: 10.1038/s41467-025-55854-6.
Transition-metal carbides have been advocated as the promising alternatives to noble-metal platinum-based catalysts in electrocatalytic hydrogen evolution reaction over half a century. However, the effectiveness of transition-metal carbides catalyzing hydrogen evolution in high-pH electrolyte is severely compromised due to the lowered proton activity and intractable alkaline-leaching issue of transition-metal centers. Herein, on the basis of validation of molybdenum-carbide model-catalyst system by taking advantage of surface science techniques, MoC micro-size spheres terminated by Al doped MoO layer exhibit a notable performance of alkaline hydrogen evolution with a near-zero onset-potential, a low overpotential (40 mV) at a typical current density of 10 mA/cm, and a small Tafel slope (45 mV/dec), as well as a long-term stability for continuous hydrogen production over 200 h. Advanced morphology and spectroscopy characterizations demonstrate that the local -Al-OH-Mo- structures within Al-MoO terminations serve as strong Brønsted acid sites that accelerate the deprotonation kinetics in alkaline HER process. Our work paves an interesting termination-acidity-tailoring strategy to explore cost-effective catalysts towards water electrolysis and beyond.
半个多世纪以来，过渡金属碳化物一直被视为电催化析氢反应中贵金属铂基催化剂的有前途的替代品。然而，由于质子活性降低以及过渡金属中心难以解决的碱性浸出问题，过渡金属碳化物在高pH值电解质中催化析氢的有效性受到严重影响。在此，基于利用表面科学技术对碳化钼模型催化剂体系进行验证，由铝掺杂的MoO层终止的MoC微米尺寸球体表现出显著的碱性析氢性能，起始电位接近零，在典型电流密度10 mA/cm²时过电位低（40 mV），塔菲尔斜率小（45 mV/dec），并且在连续产氢超过200小时的过程中具有长期稳定性。先进的形貌和光谱表征表明，Al-MoO终止结构中的局部 -Al-OH-Mo- 结构作为强布朗斯特酸位点，加速了碱性析氢过程中的去质子化动力学。我们的工作为探索用于水电解及其他领域的经济高效催化剂开辟了一种有趣的终止酸度调节策略。
