One-pot Hydrothermal Synthesis of Bifunctional Co/Mo-rGO efficient Electrocatalyst for HER/OER in Water Splitting.

Fabrication of highly efficient and earth-abundant bifunctional electrocatalyst to accelerate the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are critical for overall water splitting. In this work, bimetallic Co/Mo oxides modified reduced graphene oxide (rGO) was synthesized using a simple one-pot hydrothermal method, which significantly improved the electrocatalytic activity in both HER and OER. Under the optimal conditions, the double layer capacitance of rGO modified by Co/Mo bimetal is 78.08 mF cm−2. The overpotential required for HER to reach -10 mA cm−2 current density is 488 mV, the dynamic Tafel slope is 126 mV dec−1. The overpotential required for OER to reach 10 mA cm−2 current density is 420 mV, the slope of kinetic Tafel is 169 mV dec−1. This work provides a new prospect for the rational design and fabrication of efficient HER/OER bifunctional electrocatalysts in electrochemical energy device application.Graphical Abstract: Fabrication of highly efficient and earth-abundant bifunctional electrocatalyst to accelerate the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are critical for overall water splitting. In this work, bimetallic Co/Mo oxides modified reduced graphene oxide (rGO) was synthesized using a simple one-pot hydrothermal method, which significantly improved the electrocatalytic activity in both HER and OER. Under the optimal conditions, the double layer capacitance of rGO modified by Co/Mo bimetal is 78.08 mF cm−2. The overpotential required for HER to reach -10 mA cm−2 current density is 488 mV, the dynamic Tafel slope is 126 mV dec−1. The overpotential required for OER to reach 10 mA cm−2 current density is 420 mV, the slope of kinetic Tafel is 169 mV dec−1. This work provides a new prospect for the rational design and fabrication of efficient HER/OER bifunctional electrocatalysts in electrochemical energy device application. [ABSTRACT FROM AUTHOR]