Multi-configuration structure based on catalysis electrodes and composite membrane for efficient alkaline water splitting

Abstract

The rational design of an efficient, stable, and safe alkaline water splitting system with non-precious metal catalysts is crucial for efficient sustainable energy conversion, but their practical application still remains a significant challenge. Here we show two highly efficient catalytic electrodes, cobalt-doped nickel/iron layered double hydroxide (Co:NiFe-LDH) nanosheets and nickel/iron alloy (NiFe-Alloy) nanoparticles grown on nickel foam, for the oxygen and hydrogen evolution reactions. What’s more, a novel composite membrane through a self-cross-linked reaction between Co:NiFe-LDH nanospheres and polyvinyl alcohol (PVA) has been prepared, constructing a dual dynamic framework structure for transporting ions and water molecules. The as-prepared composite anion exchange membrane (Co:NiFe-LDH@PVA) exhibits high stretchability and mechanical strength, strong hydrophilicity, and good ionic conductivity. As a result, the alkaline water-splitting electrolyzer affords a low cell voltage of 1.419 V at 10 mA cm−2 as well as robust stability over 100 h. Our study provides a new avenue for rational design and modulation of alkaline water splitting and holds great promise for developing renewable energy.