Boosting aqueous zinc-ion storage in MoS2 via controllable phase.

• The few-layered MoS 2 nanosheets with different phase contents were prepared by an efficient controllable phase engineering. • The optimized material shows outstanding specific capacity and excellent long cycling performances. • The mechanisms involved were elucidated by systematical characterizations. • The DFT simulations reveal that the 1T phase MoS 2 has much lower Zn diffusion energy barriers. Recently, aqueous rechargeable Zn-ion batteries have attracted extensive attention, owing to their low-cost, high operational safety and environmental friendliness. However, the aqueous zinc-ion battery is still in a very infant stage, and the main challenge is to develop the ideal cathode due to the sluggish kinetics and low reversibility of divalent zinc ions. Herein, for the first time, we report controllable phase engineered few-layered MoS 2 nanosheet as cathode materials for rechargeable aqueous Zn-ion batteries and systematically study their performance. We found that the obtained MoS 2 with different phase contents showed distinct performance in the rechargeable aqueous zinc-ion battery. In particular, the MoS 2 nanosheets with ~70% 1T phase content displays excellent specific capacity and shows outstanding long-term cyclic stability. The mechanisms involved were clarified by not only comprehensive characterizations, but also the density functional theory (DFT) simulations that reveal the 1T phase MoS 2 has much lower Zn diffusion energy barriers. This study provides new insight into the effect of different phases on the performance of MoS 2 -based electrodes and will improve our understanding of developing better cathodes for the aqueous rechargeable Zn-ion batteries. [ABSTRACT FROM AUTHOR]