Applied Surface Science, Vol.489, 435-445, 2019
In situ construction of Ni enriched porous NiAl as long-lived electrode for hydrogen evolution at high current densities
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.