Cobalt phosphide nanowall arrays supported on carbon cloth: an efficient monolithic non-noble-metal hydrogen evolution catalyst

Hydrogen has been considered as an ideal energy carrier for replacing fossil fuels to mitigate global energy crises. Hydrolysis of sodium borohydride (NaBH₄) is simple and effective for hydrogen production but needs active and durable catalysts to accelerate the kinetics. In this paper, we demonstrate that cobalt phosphide nanowall arrays supported on carbon cloth (CoP NAs/CC) efficiently catalyze the hydrolytic dehydrogenation of NaBH₄ with an activation energy of 42.1 kJ mol⁻¹ in alkaline media. These monolithic CoP NAs/CC show a maximum hydrogen generation rate of $5960ml{min}^{-1}{g^{-1}}_{\left(CoP\right)}$ and are robust with superior durability and reusability. They are also excellent in activity and durability for electrochemical hydrogen evolution in 1.0 M KOH, with the need of an overpotential of only 80 mV to drive 10 mA cm⁻². They offer us a promising low-cost hydrogen-generating catalyst for applications. (paper)