Mesoporous CoMoO4 hollow tubes derived from POMOFs as efficient electrocatalyst for overall water splitting

The development of earth-abundant catalysts for electrocatalytic water splitting has attracted widespread attention. In this work, a novel catalyst of mesoporous CoMoO4 with hollow tubes (CoMoO4 HTs) was derived from polyoxometalates based metal-organic frameworks (POMOFs) and combined with calcination. The POMOFs as “preassembly platform” has been synthesized under solvothermal method by introducing H3PMo12O40 into Co-BTC system. The CoMoO4 HTs catalyst possesses remarkable catalytic activity for OER and HER in 1.0 M KOH, which displays a low overpotential of 210 mV and 75 mV at 10 mA cm-2, respectively. Moreover, the overall water splitting devise by using CoMoO4 HTs as both the anode and cathode, requires only a cell voltage of 1.57 V to attain the current density of 10 mA cm-2. Meanwhile, for the overall water splitting, CoMoO4 HTs electrocatalyst showed excellent electrochemical stability for 72 h in 1.0 M KOH. The superior electrocatalytic properties of CoMoO4 HTs can be ascribed to the high specific surface area and abundant ion transport channels endowed because of the unique porous and hollow structure. This work provides a new strategy for preparing hollow structure non-noble metal electrocatalysts with high catalytic activity.