In situ construction of Ni enriched porous NiAl as long-lived electrode for hydrogen evolution at high current densities

By Zhang, Jingtao; Zhang, Zhen; Yao, Yuanjun; Ma, Xinzhou; Yang, Yibin; Chen, Ying; Cheng, Zhengdong
Published in Applied Surface Science 2019

Abstract

The hydrogen evolution reaction (HER) is a key process in water electrolysis to produce hydrogen, but the development of highly active, stable and cost-effective monolith HER electrocatalysts by simple methods remains a great challenge. Here we report a compelling and powerful strategy to prepare a Ni enriched three-dimensional nanoporous NiAl catalyst which can be directly used as a highly active and long-lived HER electrode in acids. The electrode exhibits low onset overpotential of only ?33 mV. Overpotentials of merely ?157 mV and ?226 mV are needed to reach current densites of ?100 and ?200 mA cm?2, respectively, superior to recently reported state-of-art Ni-based monolith HER catalysts. The high activity is likely due to in situ obtained nanoporous structure with high surface area and nanosized Ni. Under a medium overpotential of ?335 mV, the electrode can sustain ?350 mA cm?2 up to 60 h, showing good long-term stability at high current density. The favorable combination of the high activity, stability, facile preparation and low-cost makes the Ni enriched nanoporous NiAl a promising electrocatalyst for high-speed hydrogen production.

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