Bifunctional nanoporous Ni-Zn electrocatalysts with super-aerophobic surface for high-performance hydrazine-assisted hydrogen production

Abstract

In the present study, an effective approach is proposed to replace OER with substituted anodic hydrazine oxidation reaction (HzOR) to assist hydrogen generation based on a bifunctional porous Ni-Zn electrocatalyst with nanosheet arrays. The Ni-Zn catalyst exhibits extraordinary HzOR performance with a high current density of 970 mA cm-2 at 0.7 V vs RHE, and 93.8% of its initial activity after 5000 s, simultaneously delivering an overpotential of 68 mV at 10 mA cm-2 for HER. Moreover, the electrolytic cell is constructed employing Ni-Zn catalysts as both anode and cathode, achieving 100 mA•cm-2 at an ultralow cell voltage of 0.497 V with an outstanding stability over 10 h. The superior electrocatalytic performance can be ascribed to its porous structure with large active surface area, high electrical conductivity, and most importantly the superaerophobic nature of Ni-Zn surface. This work also provides a novel approach to design and construct porous structured non-noble metal bifunctional electrocatalyst with superaerophobic surface used for energy-saving hydrogen production.