On Oct 8, 2020, the research group of energy materials service and protection led by Prof. Xia Baoyu, Prof. Liu Hongfang and Prof. Guo Xingpeng published a paper entitled “Preparation of Nickel-Iron Hydroxides by Microorganism Corrosion for Efficient Oxygen Evolution” on Nature Communications. This research group focuses on the combined research of traditional corrosion electrochemistry and modern energy electrochemistry, as well as the service and failure of energy materials and technology. The group aims to study and use corrosion electrochemistry to make key energy materials and improve the service quality. This work presents a microorganism corrosion strategy for preparing highly efficient electrodes towards electrocatalytic water oxidation, which not only provides efficient candidate electrocatalysts but also bridges traditional corrosion engineering and emerging electrochemical energy technologies. Dr. Yang Huan is the first author; Huazhong University of Science and Technology is the signature unit of the first author, and Prof. Xia Baoyu from the School of Chemistry and Chemical Engineering is the corresponding author of the paper.
Preparation, morphology and structure characterization of the corrosion electrode
At present, with the increasing awareness of environment protection and the increasing demand for clean energy, it is imperative to develop alternative new energy conversion and storage systems. Oxygen evolution is of great significance in several energy conversion systems including rechargeable metal-air batteries and water electrolysis devices. However, the sluggish kinetics in the complicated multiple proton/electron-processes requires highly efficient electrocatalysts. Noble metal (Ru, Ir, etc.) based nanocomposites manifest high activities, but the limited earth reserves and high cost cannot support their practical applications. Numerous earth-abundant alternatives including metal (hydro)oxides and sulfides have been developed to replace precious electrocatalysts. Among them, Ni–Fe oxides/hydroxides have been demonstrated as the excellent electrocatalysts for oxygen evolution in alkaline electrolytes. Various methods including electrodeposition and hydrothermal treatment have been developed to prepare Ni–Fe oxides/hydroxides. These bottom-up methods require the meticulous treatment of the complex precursor at stringent synthetic conditions (high temperature, voltage or pressure) to realize the precise construction of nanostructures. Therefore, the research group of energy materials service and protection led by Prof. Xia Baoyu, Prof. Liu Hongfang and Prof. Guo Xingpeng developed a top–down approach by etching metallic substrates provides new opportunities to build the integrated electrodes at mild environment. The as-prepared electrode exhibits excellent activity for oxygen evolution with an overpotential of only 220 mV needed to achieve the benchmark current density of 10 mA cm−2. X-ray synchrotron radiation absorption spectroscopy and theoretical calculations show that the synergy between the nickel-iron hydroxide produced by chemical corrosion and the iron-sulfur species produced by the metabolism of sulfate-reducing bacteria improves the catalytic activity of the corrosion electrode.
This work not only provides an efficient electrode for electrocatalytic oxygen evolution but also perhaps more importantly demonstrates an interesting and facile strategy by microorganism-assisted corrosion engineering. This work is a good demonstration that bridges the gap between traditional corrosion engineering and emerging electrochemical energy conversion technologies. Therefore, the present work is likely to stimulate high interest in the multidisciplinary integration among biology, industrial corrosion, nanomaterials design, and modern energy technologies. This research is supported by the National Natural Science Foundation of China, Huazhong University of Science and Technology, School of Chemistry and Chemical Engineering of HUST and Wuhan National Laboratory for Optoelectronics.
Link of the paper: https://www.nature.com/articles/s41467-020-18891-x
