MnOx@porous silicon as cathode material for aqueous rechargeable zinc-ion battery

Mn-based aqueous rechargeable zinc-ion batteries (ARZIBs) have caused wide attention on account of their eco-friendly, intrinsic safety and low polarization. However, the energy density of ARZIBs must be improved to be equivalent to that of commercial lithium-ion batteries, and enhanced operating voltage is one of the effective solutions. Herein, a new composite material consisting of MnOx and porous silicon (MnOx@P-Si) was synthesized and designed, and hydrophobic properties of P-Si could offset the redox reaction of H2O in the voltage window of 0–2 V. MnOx@P-Si also had good cycling stability and reversibility due to the unique structure of P-Si and the co-effect of MnSO4 and ZnSO4 in the electrolyte. Moreover, MnOx@P-Si exhibited specific capacity of 242.6 mAh g−1 at 100 mA g−1, remaining about 149.7 mAh g−1 after 400 cycles. The capacity decay per cycle of MnOx@P-Si electrode after 400 cycles was around 0.096%. Therefore, this study provided a new idea for the design of low-cost and high-performance rechargeable Mn-based ARZIBs.