3D d-Ti3C2 xerogel framework decorated with core-shell SnO2@C for high-performance lithium-ion batteries

Abstract Three-dimensional (3D) delaminated-Ti 3 C 2 (d-Ti 3 C 2 ) xerogel framework decorated with core-shell SnO 2 @C nanoparticles is constructed via PVA-assisted sol-gel process, in which SnO 2 @C nanoparticles are synthesized by one-step hydrothermal route and then encapsulated into d-Ti 3 C 2 framework. Remarkable improvement in the electrochemical performances as the lithium-ion batteries (LIBs) anode is achieved. Typically, the SnO 2 @C/d-Ti 3 C 2 xerogel framework delivers a high initial capacity (1314 mA h g −1 ) and a reversible specific capacity up to 520 mA h g −1 after 1000 charge-discharge cycles at 1.0 A g −1 . Furthermore, even at 10 A g −1 , it still achieves a reversible specific capacity of 205.6 mA h g −1 , with a discharge capacity of 169 mA h g −1 and a coulombic efficiency of 99.5% after 1000 cycles. Such excellent electrochemical performances are attributed to the synergistic effect between core-shell SnO 2 @C and 3D d-Ti 3 C 2 conductive network: (i) the core-shell structure suppresses the pulverization of SnO 2 during the Li insertion/extraction process, and (ii) the interconnected 3D MXene framework establishes a good conductive pathway for fast lithium ions diffusion and quick charge transfer.