Efficient Water Splitting System Enabled by Multifunctional Platinum‐Free Electrocatalysts
Yaotang Zhong, Yitong Lu, Zhenghui Pan, Jie Yang, Guohao Du, Jiawei Chen, Qiankui Zhang, Hebing Zhou, John Wang, Chunsheng Wang, Weishan Li
Abstract
Abstract Tremendous research efforts have been focused on the development of a water splitting system (WSS) to harvest hydrogen fuels, but currently available WSSs are complicated and cost‐ineffective mainly due to the applications of noble platinum or different electrocatalysts. Herein, a novel WSS comprising electricity generation from solar panels, electricity storage in rechargeable zinc–air batteries (ZABs), and water splitting in electrolyzers, enabled by hybrid cobalt nanoparticles/N‐doped carbon embellished on carbon cloth (Co–NC@CC) as multifunctional platinum‐free electrocatalysts is reported. Consequently, the Co–NC@CC electrode presents excellent trifunctional electrocatalytic activity with an onset potential of 0.94 V for oxygen reduction reaction, and an overpotential of 240 and 73 mV to achieve a current density of 10 mA cm −2 for oxygen and hydrogen evolution reactions, respectively. For a proof‐of‐concept application, a rechargeable ZAB assembled from the high‐performance Co–NC@CC air cathode exhibits a high open circuit potential of 1.63 V and a superior energy density of 1051 Wh kg −1 Zn . Furthermore, an overall water splitting electrolyzer constructed by the symmetrical Co–NC@CC electrodes delivers a current density of 10 mA cm −2 at a low cell voltage of 1.57 V. Such a solar‐powered WSS can harvest hydrogen day and night, demonstrating a potential for application in sustainable renewable energy.