Flatten the Li‐ion Activation in Perfectly Lattice‐Matched MXene and 1T‐MoS2 Heterostructures via Chemical Functionalization

Abstract

AbstractThe complexity of the ionic and electronic dynamics in MXene based hybrids, which are normally involved for device integration, triggers both challenges and opportunities for its application. Herein, as a prototype of metallic hybrids of MXene, heterostructures consisting of Ti3C2T2 (T = None, O and F atoms) and metallic MoS2 (1T phase) are investigated for lithium‐ion battery (LIB) applications. It is found that different surface atomic groups in MXene significantly alter the affinity, redox reaction and kinetics of Li atoms in the interface of the Ti3C2T2 and 1T‐MoS2. Through examining the three possible pathways of Li by first‐principles calculations and ab‐initio molecular dynamics, the diffusion curve becomes significantly flattened from the naked to O‐ and F‐terminated Ti3C2 MXene with activation barriers reducing dramatically from 0.80 to 0.22 and 0.29 eV, respectively, and accordingly promoted diffusion coefficients. The functionalization with O or F eliminates the steric hindrance of Li intercalation by breaking the strong interaction between two layers and provides additional adsorption sites for Li diffusion in the meantime. The work suggests that surface functional groups play a significant role in Ti3C2T2/1T‐MoS2 modification and similar strategy via chemical modification of metallic hybrids provides hints for designing high performance anode material for LIBs.