Non-desolvation Zn2+storage mechanism enables MoS2anode with enhanced interfacial charge-transfer kinetics for low temperature zinc-ion batteries

The emerging rocking-chair aqueous zinc-ion battery (AZIB) configuration provides a promising approach for realizing their practical applications by avoiding the critical drawbacks of Zn metal anodes including unsatisfactory Coulombic efficiency and low Zn utilization. Therefore, exploiting appropriate insertion-type anodes with fast charge-transfer kinetics is of great importance, and many modifications focusing on the improvement of electron transport and bulk Zn2+diffusion have been proposed. However, the interfacial Zn2+transfer determined by the desolvation process actually dominates the kinetics of overall battery reactions, which is mainly overlooked. Herein, the interlayer structure of MoS2is rationally co-intercalated with water and ethylene glycol (EG) molecules (MoS2@EG), giving rise to a fast non-desolvation Zn2+storage mechanism, which is verified by the extraordinarily smaller activation energy of interfacial Zn2+transfer (4.66 kJ mol−1) compared with that of pristine MoS2(56.78 kJ mol−1). Furthermore, the results of theoretical calculations, in-situRaman and ex-situcharacterizations also indicate the enhanced structural integrity of MoS2@EG during cycling due to the enlarged interlayer spacing and charge screening effect induced by interlaminar EG molecules. Consequently, the MoS2@EG anode enables excellent cycling stability of both high-energy-density MoS2@EG∥PVO (polyaniline intercalated V2O5) and high-voltage MoS2@EG∥Na3V2(PO4)2O2F (NVPF) full batteries with neglectable capacity decay at −20 °C.