Hydrogen could help to face the challenges of rising global energy consumption and climate change, as it can store energy from renewable sources and release it in fuel cells, with only water as a product. However, generating hydrogen via the electrolysis of water depends on electrocatalysts, which are often rare noble metals with high costs, such as platinum. There is a need for economically viable noble‐metal free catalysts with good activity and long‐term stability.

Qingsheng Gao, Jinan University, Guangzhou, China, Yi Tang, Fudan University, Shanghai, China, and colleagues have developed nanowires composed of a mixture of molydenum carbides (MoC and Mo₂C), which show excellent activity for the hydrogen evolution reaction. The nanowires were synthesized by reacting molybdate with aniline derivatives, and subsequent carbonization at 700–775 °C. Varying the amount and type of aniline allowed the team to tune the carbon content and thus the ratio of MoC and Mo₂C in the nanowires. Optimal performance was found for 31.4 % MoC by weight.

The resulting material’s catalytic activity was tested after fixing it onto glassy carbon electrodes. The nanowires show a low overpotential for hydrogen evolution, good stability under both basic and acidic conditions, and excellent activity compared to other noble-metal free catalysts.

• Heteronanowires of MoC-Mo₂C as Efficient Electrocatalysts for Hydrogen Evolution Reaction,
  Huanlei Lin, Zhangping Shi, Sina He, Xiang Yu, Sinong Wang, Qingsheng Gao, Yi Tang,
  Chem. Sci. 2016.
  DOI: 10.1039/C6SC00077K