SnO/SnO<sub>2</sub> Heterojunction Nanoparticles Anchored on Graphene Nanosheets for Lithium Storage
Shujuan Yin, Xueqian Zhang, Xiaoxiao Huang, Fei Zhou, Yishan Wang, Guangwu Wen
Abstract
Engineering heterojunction composite structures consisting of multiple nano active components formed from single element is broadly acknowledged as a robust method to boost the electrochemical performance of lithium-ion batteries (LIBs). Herein, a multidimensional composite structure consisting of SnO/SnO 2 heterojunction nanoparticles and reduced graphene oxide nanosheets (SnO/SnO 2 @G) is proposed. The extensive empirical characterization and density functional theory (DFT) calculations validate the plentiful heterogeneous interfaces and resilient lithium storage mechanism exhibited by the SnO/SnO 2 heterostructures. These attributes are closely associated with the rapid diffusion kinetics of Li + within the space charge region and the presence of multiple-ion channels. On the other hand, the Sn–O–C bond is anchored on graphene sheets, enhancing SnO/SnO 2 heterostructure stability and preventing unavoidable aggregation and slow charge transfer. As anticipated, the better specific capacity, rate performance, and cycling stability (498.69 mAh g –1 at 1.0 A g –1 after 400 cycles) are acquired in the LIBs composed of a SnO/SnO 2 @G anode. This work provides a feasible approach for improving the performance of LIBs by constructing single-element heterostructures.