Superhydrophilic Ni-based Multicomponent Nanorod-Confined-Nanoflake Array Electrode Achieves Waste-Battery-Driven Hydrogen Evolution and Hydrazine Oxidation

The low thermodynamic potential (-0.33 V) and safe by-product of N-2/H2O, make utilizing hydrazine oxidation reaction (HzOR) to replace thermodynamically-unfavorable and kinetically-sluggish oxygen evolution reaction a promising tactic for energy-efficient hydrogen production. However, the complexity of bifunctionality increases difficulties for effective material design, thus hindering the large-scale hydrogen generation. Herein, we present the rationally designed synthesis of superhydrophilic Ni-based multicomponent arrays (Ni NCNAs) composed of 1D nanorod-confined-nanoflakes (2D), which only needs -26 mV of working potential and 47 mV of overpotential to reach 10 mA cm(-2) for HzOR and HER, respectively. Impressively, this Ni NCNA electrode exhibits the top-level bifunctional activity for overall hydrazine splitting (OHzS) with an ultralow voltage of 23 mV at 10 mA cm(-2) and a record-high current density of 892 mA cm(-2) at just 0.485 V, also achieves the high-speed hydrogen yield driven by a waste AAA battery for OHzS.

Automated summary

In this study, superhydrophilic Ni-based multicomponent arrays were successfully designed and synthesized, allowing for hydrazine oxidation reaction and hydrogen evolution reaction to occur at very low working potentials with excellent bifunctional activity for overall hydrazine splitting.