Boosting hydrogen evolution activity in alkaline media with dispersed ruthenium clusters in NiCo-layered double hydroxide

By Li, Dan; Zhang, Bowei; Li, Yang; Chen, Rongsheng; Hu, Shan; Ni, Hongwei
Published in Electrochemistry Communications 2019

Abstract

Herein, we report a hybrid electrocatalyst consisting of Ru clusters trapped in NiCo-layered double hydroxide (NiCo-LDH) as the basis for an efficient hydrogen evolution reaction (HER) in alkaline media. Benefiting from the fast water dissociation kinetics on NiCo-LDH and favorable H recombination on Ru, the resultant Ru-NiCo-LDH shows an extremely low HER overpotential of 28 mV at a current density of 10 mA cm?2 with a small Tafel slope of 42 mV dec?1. This superior catalytic activity can be ascribed to its high charge transfer ability and to the synergistic effect of the highly dispersed Ru and the NiCo-LDH. Moreover, we also found that the oxidized Ru incorporated in NiCo-LDH was entirely reduced to Ru0 under hydrogen-evolution conditions, which suggests that Ru0 is the true catalytically active phase responsible for the outstanding HER performance.

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