Multipronged Fabrication of Co3Se4 Wrapped into N‐Doped Multiwall Carbon Nanotubes Tangled Hollow Dodecahedron Framework for Overall Water Splitting under Benign Condition

Abstract

AbstractIn this work, a synergistic strategy is proposed to synthesize a high‐performance bifunctional electrocatalyst (marked as Co3Se4/N‐CNTs) for neutral water splitting, in which Co3Se4 nanoparticles are wrapped into N‐doped multiwall carbon nanotubes assembled hollow dodecahedron framework. The neutral‐oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) catalytic performances of Co3Se4/N‐CNTs are maximally optimized by regulating nanostructure engineering, element doping, and carbon coating. In 1 m phosphate buffer solution (PBS) electrolyte, Co3Se4/N‐CNTs catalyst exhibits superior stability and catalytic activity for OER and HER, yielding a geometrical catalytic current density of 10 and −10 mA cm−2 at rather low overpotentials of 385 and 102 mV, respectively, meanwhile operating continuously for 35 h without obvious polarization increase. It is worth mentioning here, when a neutral electrolyzer is assembled, Co3Se4/N‐CNTs‖ Co3Se4/N‐CNTs cell contributes a high performance for overall water splitting in 1 m PBS electrolyte, delivering a current density of 10 mA cm−2 at a low applied external potential of 1.75 V, and displaying satisfying operation stability without evident deactivation after 35 h. The catalytic performances rival those of catalysts operated under moderate conditions. Consequently, all the merits promise that Co3Se4/N‐CNTs is an attractive bifunctional catalyst for hydrogen fuel production and storage of intermittent renewable energy sources under environmentally friendly conditions.