Self-supportive Pd0.2Ni58Fe30O11.8 nanowires for solar-driven self-powered water/seawater splitting with large current density

Abstract

Solar-driven water/seawater splitting system is a significant renewable technology for obtaining hydrogen fuel, while the drawbacks of sunlight with intermittent and unstable limit their widespread practical applications. It is an efficient and renewable way to add an energy storage module between the photovoltaic system and electrolyzer to operate a self-powered and uninterrupted electrolyzer for improving the development of solar-driven water/seawater splitting. Herein, we develop an efficient and stable trifunctional electrocatalyst of self-supportive Pd0.2Ni58Fe30O11.8 nanowires for Zn-air batteries and overall seawater splitting, which connect with photovoltaic cells to assemble solar-driven self-powered electrocatalytic water splitting system. It is noticed that the obtained self-supportive Pd0.2Ni58Fe30O11.8 nanowires show a special 3D network structure connected by nanowires with a hierarchical structure, improving the charge and mass transfer on their surface. Furthermore, the self-supportive Pd0.2Ni58Fe30O11.8 nanowires displayed low overpotentials of 77 and 233 mV to deliver current densities of 100 mA cm−2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) processes, which is at the top level of great prospects for industrialization. A highly efficient and stable 24-hour integral water exchange system was successfully established with a circuit output voltage of 1.88 V and constant and stable current density throughout the system. The solar-powered uninterrupted overall water-splitting systems open up exciting opportunities for fully renewable and sustainable energy applications.