Pseudo-Perovskite Oxide with in Situ Surface Reconstructed Metals for Alkaline Hydrogen Evolution

The development of non-noble-metal electrocatalysts for the hydrogen evolution reaction (HER) at industrial current densities is essential for advancing alkaline water electrolysis. Herein, a pseudo-perovskite oxide-based Ni-monolithic electrode integrated with nanosocketed CoNi particles (CoNi-La 0.6 Sr 0.4 Co 0.8 Fe 0.2 O 3−δ, denoted CoNi-LSCF) was developed via the in situ growth of bimetallic CoNi nanoparticles on perovskite oxide. The CoNi-LSCF electrode exhibited a promising alkaline HER performance, achieving an overpotential of 28 mV at 10 mA cm –2 and a low Tafel slope of 24 mV dec –1 . Additionally, the electrode maintained stable operation for over 1000 h at 1 A cm –2 . The enhanced catalytic activity and long-term stability are attributed to the synergistic interaction between CoNi nanoparticles and the pseudo-perovskite oxide, which optimizes water dissociation and hydrogen adsorption/desorption at the electrode surface. This study introduces a viable approach to designing efficient and durable electrocatalysts that offers a scalable solution for practical water electrolysis systems.