Structural engineering of metal oxyhydroxide for electrochemical energy conversion and storage

In electrochemical energy conversion and storage (EECS) technologies, developing highly active electrocatalysts and electrode materials with improved electrochemical and cycling activities has been a crucial study for many decades. The metal oxyhydroxides (MOOHs) are robust materials searching for new nanostructured catalysts/electrodes with enhanced electrochemical performance and desired structural and composite characteristics. Their recent advances in defect engineering are very inspiring. Herein, we discuss the advantages and present the accomplishments of various MOOHs (M = mono-, bi-, and mixed-metal) in EECS systems, including supercapacitors, alkali metal ion batteries, and hydrogen and oxygen evolutions via water electrolysis. We thoroughly discussed the design and synthetic strategies of MOOH with the control of distinct promises for EECS. Additionally, we highlighted useful accessibilities to unravel practical and scientific interpretations in targeting MOOH products for EECS. Finally, we concisely proposed the existing difficulties and directions for future consideration.