Improving the electrochemical performance of SnO2 anode materials via glassy interface construction

Abstract

Despite the ideal specific theoretical capacity, SnO2-based electrode materials, considered potential anode materials, face challenges due to serious volume expansion and poor safety performance. In this study, we propose a novel approach called SnO2/Li2O–B2O3 (SLB), where SnO2 is cladded with a Li2O–B2O3 interface construction. This glassy flexible matrix effectively fixes the active particles within the framework, curbing volume expansion, and facilitating high-efficiency ion transport. Additionally, the presence of the glassy interface construction converts the well-known irreversible conversion/inversion reaction into a reversible process, resulting in a significant enhancement of the coulombic efficiency. At a current density of 0.5 A g−1, SLB demonstrates improved cycling stability with a capacity of 566.3 mAh g−1 after 300 cycles. Even at a higher current density of 1.0 A g−1, the capacity remains at 363.4 mAh g−1 after 800 cycles. Moreover, the artificial protection layer, composed of the Li2O–B2O3/Sn interface construction matrix, greatly enhances the flame resistance of the electrode material at abnormally high temperatures, thanks to the excellent thermal stability of the flexible glassy matrix. This interface modification represents a promising approach to address the challenges and significantly advance the commercialization of SnO2-based anode materials.