Electrodeposition of Metal-Free Polyaniline Electrocatalyst for Efficient Oxygen Evolution in Acid

Developing efficient and competitive electrocatalysts for the oxygen evolution reaction (OER) in acid is a great challenge for hydrogen production. Compared with metal catalysts, metal-free catalysts are more environmentally friendly and cheaper. Herein, we present a novel non-metallic self-supporting polyaniline catalyst (PANI3/CFP) synthesized by electrodeposition for efficient water oxidation. Benefiting from the three-dimensional network structure, excellent conductivity, and large number of nitrogen functional groups, PANI3/CFP exhibits high activity towards OER. At a current density of 10 mA cm(-2), PANI3/CFP delivers a low overpotential of 204 mV in 0.1 m HClO4, much lower than commercial Ir/C and previously reported acidic OER catalysts. Besides, the turnover frequency (TOF) value of PANI3/CFP reaches 0.0456 s(-1) at 1.5 V versus the reversible hydrogen electrode (vs. RHE). Analysis of structure and electrocatalytic performances reveal that =N- species in polyaniline are the main active sites for acidic OER. This work provides a unique strategy for the design of non-metallic acidic OER catalysts.