Interfacial engineering of Ru-doped Co3O4/CoP nanowires heterostructure as efficient bifunctional electrocatalysts for alkaline water splitting

Abstract

Designing a highly efficient bi-functional electrocatalyst for boosting both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is urgent and promising in hydrogen produce by water splitting. Here, a simple wet-chemical route followed by continuous oxidation and partial phosphorylation treatments is adopted to prepare the Ru doped Co3O4 and CoP heterojunction nanowires on Ti mesh (Ru-Co3O4/CoP/TM). Benefit from the more active sites from the heterointerfaces and synergetic cooperation between Co3O4 and CoP phase, the catalyst showed high electrocatalytic activity in alkaline solutions. It only required the overpotentials of 47 and 293 mV to deliver a current density of 10 mA cm−2 toward HER and OER in 1 M KOH medium, respectively. For overall water splitting (OWS), using Ru-Co3O4/CoP/TM as both the cathode and anode, it required an ultra-low cell voltage of 1.66 V to operate the current density of 20 mA cm–2, and it also remained a robust stability during the electrocatalysis process.