Self-powered electrolysis systems for sustainable hydrogen generation from natural seawater via a Ni/V2O3 Schottky electrode

Abstract

Developing novel and efficient techniques for extracting hydrogen from natural seawater sustainably via electrolysis is highly attractive, yet remains a great challenge. Herein, a self-powered electrolysis system (SPES) driven by Mg/seawater batteries (MSBs) with a Ni/V2O3 Schottky electrode is demonstrated for sustainable production of hydrogen from seawater. The Ni/V2O3 Schottky electrode is constructed to serve as the hydrogen evolution reaction (HER) cathode for both the MSBs and seawater electrolysis unit in the SPES, enabling facile seawater HER with 10 and 1000 mA cm−2 at low overpotential of 176 and 649 mV respectively. The MSB with the Ni/V2O3 Schottky cathode delivers a peak power density up to 17.81 mW cm−2. Importantly, the designed SPES achieves a high hydrogen production rate up to 12.42 mL cm−2 h−1 from natural seawater with a high energy conversion efficiency of 80.87 %. This work offers an intriguing technique for in-situ sustainable acquisition of hydrogen from natural seawater.