Electronic structure tailoring of CuCo2O4 for boosting oxygen evolution reaction

Electronic structure tuning in metal oxides is a facile and effective strategy on boosting their catalytic oxygen evolution reaction (OER) performance. Here, we demonstrate the electronic structure tuning of CuCo2O4 by phosphorus (P) doping via in-situ diffusion method. The results suggest that due to more electrons transferred from P to the neighboring Co3+, the tuned Co is served as catalytic active sites for the enhanced OER performance. The synthesized P3.85-CCO/NF exhibits an overpotential of 250 mV at a current density of 10 mA cm−2, and a Tafel slope of 27 mV dec−1, which performs an enhanced OER activity than that of IrO2/NF. Moreover, the P3.85-CCO/NF presents stable electrochemical performances upon long-time running for 30 h. Thus, the electronic structure tuning strategy by in-situ P diffusion method emerges as an effective approach on enhancing the catalytic OER performance for metal oxide electrocatalysts.