Fig. 4: Near barrier-free Zn²⁺ dynamics of AOH-VO in AZIBs.

a Schematic diagram of activation energies for Zn²⁺ diffusion in the electrolyte, across the interface, and in the solids. b Zn²⁺ diffusion coefficients in the electrolyte and the solids of AOH-VO, AOH-VO-300, and VEG. c Temperature-dependent Zn²⁺ diffusion kinetics for four consecutive cycles of AOH-VO. d The evolution of activation energy for Zn²⁺ diffusion in AOH-VO during the charge-discharge process. Error bars indicate the standard deviation of the four cycles experiments. e DRT plots of AOH-VO, AOH-VO-300, and VEG under the open circuit potential at 20 °C. f The DRT plots of AOH-VO during reversible Zn²⁺ insertion/extraction processes.