Spinel-structured metal oxide-embedded MXene nanocomposites for efficient water splitting reactions

Abstract

A nanoplatelet-like spinel metal oxide grain-decorated MXene composite was successfully synthesized via a hydrothermal reaction. The prepared MXene/Co3O4 and MXene/Fe3O4 nanocomposites possessed higher porosity than their pristine counterparts, realizing outstanding bifunctional electrocatalytic activity for hydrogen and oxygen evolution kinetics in alkaline media and requiring relatively low overpotentials of 52 and 63 mV and 270 and 310 mV vs. RHE for hydrogen and oxygen evolution, respectively. The spinel-structured metal oxide MXene-decorated sheet composites exhibited robust continuous hydrogen and oxygen evolution reactions over 24 h, confirming their excellent catalytic properties. Furthermore, a prototype two-electrode device was assembled with MXene/Co3O4||Mxene/Co3O4, which required a low cell voltage (1.51 V) for water splitting with robust continuous operation over 24 h, confirming the remarkable performance of the composite for water splitting reactions. Thus, the designed spinel-structured metal oxide-decorated MXene nanocomposites are outstanding candidates for application in future green energy conversion devices.