Activating CoOOH Porous Nanosheet Arrays by Partial Iron Substitution for Efficient Oxygen Evolution Reaction

Iron-substituted CoOOH porous nanosheet arrays grown on carbon fiber cloth (denoted as FexCo1-xOOH PNSAs/CFC, 0x0.33) with 3D hierarchical structures are synthesized by insitu anodic oxidation of -Co(OH)(2) NSAs/CFC in solution of 0.01m (NH4)(2)Fe(SO4)(2). X-ray absorption fine spectra (XAFS) demonstrate that CoO6 octahedral structure in CoOOH can be partially substituted by FeO6 octahedrons during the transformation from -Co(OH)(2) to FexCo1-xOOH, and this is confirmed for the first time in this study. The content of Fe in FexCo1-xOOH, no more than 1/3 of Co, can be controlled by adjusting the insitu anodic oxidation time. Fe0.33Co0.67OOH PNSAs/CFC shows superior OER electrocatalytic performance, with a low overpotential of 266mV at 10mAcm(-2), small Tafel slope of 30mVdec(-1), and high durability.