CoFe2O4 surface modification with conducting polypyrrole: employed as a highly active electrocatalyst for oxygen evolution reaction

Abstract

Electrochemical water splitting could be a potentially viable technique for obtaining the energy from renewable sources. The considerable overpotential demanded for sluggish oxygen evolution reaction (OER), however, prevents broad adoption of this approach. Herein, CoFe2O4/PPY hybrid is synthesized with a polypyrrole layered on the top of the CoFe2O4 via facile hydrothermal treatment. CoFe2O4/PPY is a highly efficient electrocatalyst, because it outperforms than pure CoFe2O4, PPY in terms of OER. CoFe2O4/PPY OER activities are comparable to those of commercial electrocatalysts. It's worth noting that the CoFe2O4/PPY hybrid is significantly more stable than the individuals, due to surface coated with PPY, responsible for good conduction of fast-moving electrons. The CoFe2O4/PPY coupling increases the OER by promoting electron exchange between the PPY layer and the CoFe2O4 reducing the over potential of (274 mV) and also lower the Tafel slope (47 mV/dec) with lower charge transfer resistance (3.15 ohm). According to the findings, on the top of CoFe2O4, a layer of PPY is applied for the surface modification using a conducting polymer can improve spinel oxides activity for future applications such as photoelectrocatalytic study, for stabilizing the material activity, etc.