Highly Efficient g-C3N4 Nanorods with Dual Active Site as an Electrocatalyst for the Oxygen Evolution Reaction

Abstract

Finding metal-free, carbon-based, highly active, and durable electrocatalyst for oxygen evolution reaction (OER) is essential for the development of electrochemical energy storage and conversion systems. Herein, we report the synthesis of graphitic carbon nitride (g-C3N4) nanorods using a hydrothermal method. The transformation of bulk g-C3N4 (denoted as g-B-CN) to g-C3N4 1D nanorods (denoted as g-CN) endowed the material with abundant active sites, increased electrochemical active surface area, and enhanced charge transfer. g-CN exhibited high activity and durability in catalyzing the OER. The optimized g-CN achieved a current density of 10 mA cm(-2) at an overpotential of 316 mV vs. RHE in 1 M KOH, with a Tafel slope of 125 mV dec(-1). The high catalytic performance of g-CN is mainly attributed to the abundantly exposed unique active sites originatingfrom the 1D morphology and the presence of an oxidized pyridinic nitrogen; elucidating the important role of elaborate morphology tailoring and co-doping of heteroatoms in catalyzing the OER.