High-performance F, Mn co-doped VO2(B) cathode material in the form of multilayered nanosheets curled rods and its aqueous zinc ion battery applications

Abstract

To address the shortcomings of VO₂(B) when utilized as cathode materials for aqueous zinc ion batteries (AZIB), this study prepared a fluorine and manganese co-doped VO₂(B) with a nanorod-like structure, formed from convoluted multilayered nanosheets, was synthesized via a solvothermal method. It was established that F and Mn doping effectively broadens the lattice structure and tunneling space of VO₂(B) and induces lattice distortion of VO₂(B) through the high electronegativity of F element, leading to the ductile growth of FMVO into a nanorod-like structure made of multilayered ultrathin nanosheets curled. The increased tunneling space and active sites of FMVO, compared to pure VO₂(B), significantly enhanced the de-embedding rate of Zn²⁺ and reduced diffusion resistance. The specific capacity of F_0.06M_0.02VO is 523.92 mAh/g (0.2 A/g) with 88.64 % capacity retention after 2,000 cycles (5 A/g). This research provides a novel approach to the development of cathode materials for AZIB.