Multidimensional defects tailoring local electron and Mg2+ diffusion channels for boosting magnesium storage performance of WO3/MoO2

Abstract

Defect engineering presents great promise in addressing lower specific capacity, sluggish diffusion kinetics and poor cycling life issues in energy storage devices. Herein, multidimensional (0D/2D/3D) structural defects are constructed in WO3/MoO2 simultaneously via competing for and sharing with O atoms during simple hydrothermal process. 0D and 2D defects tailor local electron, activating more sites and generating built-in electric fields to yield ion reservoir, meanwhile, 3D defect owning lower anisotropic property tailors Mg2+ diffusion channels to fully exploit Mg2+ adsorbed sites induced by 0D and 2D defects, enhance the kinetics and maintain structural stability. Benefitted from synergistic effect of 0D/2D/3D structural defects, the designed WO3/MoO2 shows the higher specific capacity (112.8 mA h g−1 at 50 mA g−1 with average attenuation rate per cycle of 0.068%), superior rate capability and excellent cycling stability (specific capacity retention of 80% after 1500 cycles at 1000 mA g−1). This strategy provides design ideas of introducing multidimensional structural defects for tailoring local electron and microstructure to improve energy storage property.