Dual-modification of oxygen vacancies and PEDOT coating on MnO2 nanowires for high-performance zinc ion battery

MnO 2 has outstanding potential for application in cathode materials of zinc ion batteries (ZIBs). However, the poor electrical conductivity , poor ion diffusion kinetics, and structural instability greatly limit its rate performance, specific capacity, and cycling stability. Herein, we prepared PEDOT-coated MnO 2 cathode material with oxygen vacancy defects, namely Vö-MnO 2 @PEDOT, by Dual-modification of MnO 2 nanowires. The PEDOT coating optimizes the electron transfer capability of the material while inhibiting the dissolution of MnO 2 . The oxygen vacancies accelerate ion diffusion. Vö-MnO 2 @PEDOT possesses a joint energy storage mechanism, containing the insertion/extraction of H + /Zn 2+ and dissolution/precipitation of MnO 2 . This joint energy storage mechanism explains the high specific capacity and the increase in capacity. The Vö-MnO 2 @PEDOT displays a high specific capacity of 400 mAh/g at 0.2 A/g. Besides, at 2 A/g, Vö-MnO 2 @PEDOT outputs a high capacity of 213 mAh/g after 2000 cycles. This research provides a feasible research idea for the performance optimization of manganese oxide cathode materials.