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

Abstract

The low thermodynamic potential (-0.33V) and safe by-product of N2 /H2 O, make utilizing hydrazine oxidation reaction (HzOR) to replace thermodynamically-unfavorable and kinetically-sluggishoxygen 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 -26mV of working potential and 47mV of overpotential to reach 10mA 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 23mV at 10mA cm-2 and a record-high current density of 892mA cm-2 at just 0.485V, also achieves the high-speed hydrogen yield driven by a waste AAA battery for OHzS.