Magnetic field-assisted microbial corrosion construction iron sulfides incorporated nickel-iron hydroxide towards efficient oxygen evolution

Abstract

Nickel iron (hydroxyl) hydroxide with unique layered structure and controllable composition is widely regarded as typical oxygen evolution reaction (OER) catalysts. Recently, developing top-down approaches to realize the facile preparation of transition metal hydroxide catalyst has received wide attention. Based on the natural microorganism corrosion behavior, this work demonstrates the external magnetic field-assisted microbial corrosion strategy to construct advanced transition metal hydroxide OER catalyst, and the prepared biofilm electrode presents superior OER performance in the existence of magnetic field, which needs an overpotential of 287 ​mV at 100 ​mA ​cm−2. Experimental and theoretical calculations show the applied magnetic field can accelerate sulfate reducing bacteria (SRB) corrosion and chemical corrosion. The additional magnetic field can promote SRB corrosion to produce FeS, which can facilitate the optimization of O intermediate desorption from the NiOOH catalyst during OER process, reducing the reaction energy barrier for O→OOH. The synergistic effect between the nickel-iron oxyhydroxides originated from the accelerated chemical corrosion and FeS produced from the accelerated SRB corrosion interprets the improved OER activity. This work explores the influence of magnetic field on the construction of advanced OER materials, which can provide an effective magnetic field-assisted corrosion engineering strategy, and promote the development of multidisciplinary fields of physics, biology, and emerging energy conversion technologies.