Interface and energy band manipulation of Bi2O3-Bi2S3 electrode enabling advanced magnesium-ion storage

Rechargeable magnesium-ion (Mg-ion) batteries have attracted wide attention for energy storage. However, magnesium anode is still limited by the irreversible Mg plating/stripping procedure. Herein, a well-designed binary Bi 2 O 3 -Bi 2 S 3 (BO-BS) heterostructure is fulfilled by virtue of the cooperative interface and energy band engineering targeted fast Mg-ion storage. The built-in electronic field resulting from the asymmetrical electron distribution at the interface of electron-rich S center at Bi 2 S 3 side and electron-poor O center at Bi 2 O 3 side effectively accelerates the electrochemical reaction kinetics in the Mg-ion battery system. Moreover, the as-designed heterogenous interface also benefits to maintaining the electrode integrity. With these advantages, the BO-BS electrode displays a remarkable capacity of 150.36 mAh g −1 at 0.67 A g –1 and a superior cycling stability. This investigation would offer novel insights into the rational design of functional heterogenous electrode materials targeted the fast reaction kinetics for energy storage systems.