V4C3Tx MXene:A promising active substrate for reactive surface modification and the enhanced electrocatalytic oxygen evolution activity

Presented are the synthesis,characterizations,and reactive surface modification(RSM)of a novel nine atomic layered V4C3Tx MXene.With the advantages of the multilayered V4C3Tx MXene that can simultaneously support the RSM reaction and keep the inner skeleton stable,a series of amorphous Ni/Fe/Vternary oxide hydroxides thin layer can be successfully modified on the surface of the V4C3Tx MXene(denoted as MOOH@V4C3Tx,M=Ni,Fe,and V)without disrupting its original structure.Attributed to the in situ reconstruction of highly active oxide hydroxide layer,the nanohybrids exhibited an enhanced oxygen evolution reaction(OER)activity and excellent long-time stability over 70 hours.In particular,a current density of 10 mA cm−2 can be reached by the nanohybrid with the optimized Ni/Fe ratio at an overpotential(η)as low as 275.2 mV,which is comparable to most of the state-of-the-art OER catalysts and better than other MXene-based derivatives.Demonstrated by the tunable physicochemical properties and excellent structural stability of these nanohybrids,we may envision the promising role of the M4X3-based MXenes as substrates for a wide range of energy conversion and storage materials.