Rapid In-situ Growth of Oxygen-defect Rich Fe(OH)3@Co(OH)2@NF Nanoarray as Efficient OER Electrocatalyst

Abstract In this work, oxygen-defect rich Fe(OH)3@Co(OH)2@NF nanoarray (which is denoted as FCN) was synthesized via a facile sacrificial template-accelerated hydrolysis (STAH) method. The introduced oxygen vacancies during the incorporation of Fe3+ reduced the adsorption barrier of -OH, and enhanced the conductivity of the material. In addition, morphology and phase transformation, amorphous regions between the crystalline heterojunction surfaces give FCN nanoarray higher surface area with more active sites, which enhances the oxygenation performance. Consequently, oxygen-defect rich FCN nanoarray possessed a low OER overpotential of 225.8 mV at 50 mA cm−2.