Efficient NiFeCr0.1/NF by incorporating chromium to boost OER catalysis

This study developed ternary NiFeCr hydroxide microsphere composites for efficient oxygen evolution reaction (OER) in alkaline water. Compared to binary NiFe composites, the ternary composites exhibited superior electrocatalytic activity. In a 1 M KOH solution, the ternary composite demonstrated a low initial potential of 1.46 V (RHE), and the overpotential is only 268 mV @ 100 mA cm−2. Charge rearrangement due to chromium oxidation helped maintain iron's low oxidation state, preserving OER activity. The redistribution of chromium particles stabilized iron and prevented its dissolution in an alkaline solution. Consequently, the optimized NiFeCr catalyst exhibits excellent stability, with a stability of 200 h at 100 mA cm−2. This study offers a novel approach to designing efficient and stable catalysts for water decomposition.