Non-desolvation Zn2+ storage mechanism enables MoS2 anode 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 MoS2 is 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-situ Raman and ex-situ characterizations 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 parallel to PVO (polyaniline intercalated V2O5) and high-voltage MoS2@EG parallel to Na3V2(PO4)(2)O2F (NVPF) full batteries with neglectable capacity decay at -20 degrees C.