SnO2/Cu3Sn nanoparticles uniformly encapsulated into N-doped carbon nanofibers by electrospinning as anodes for lithium-ion batteries

A facile and feasible strategy is carried out combined with the subsequent heat treatments to encapsulate SnO 2 /Cu 3 Sn nanoparticles into N-doped carbon nanofibers (CNFs) by electrospinning to fabricate the SnO 2 /Cu 3 Sn@CNFs nanofibers as anode materials for lithium-ion batteries. The one-dimensional composite nanofibers are well interconnected with each other and randomly intertwined to construct the distinctive three-dimensional networks, which not only shorten Li + transfer pathways and accelerate Li + diffusions in the axial direction, but also improve the electronic conductivity of whole composite electrodes. Furthermore, the fully active SnO 2 phases dominate the lithium storage behaviors of composite electrodes to guarantee the excellent lithium storage capacity, and the relatively active Cu 3 Sn phases play the role of buffer matrixes to accommodate the huge volume expansion of SnO 2 phases. When the dosages of SnCl 2 salts are controlled at 5 mmol, the SnO 2 /Cu 3 Sn@CNFs-5 electrode delivers the excellent comprehensive electrochemical properties, whose initial discharge specific capacity is 1279.1 mAh/g at 100 mA/g and maintains to 560.7 mAh/g after 200 cycles. Moreover, the SnO 2 /Cu 3 Sn@CNFs-5 electrode is endowed with the high-specific capacity of 359.2 mAh/g at 500 mA/g after 1000 cycles and the satisfactory pseudocapacitive contribution of 49.60% at 1.0 mV/s. The new insights into the electrospinning strategy of encapsulating SnO 2 and Cu 3 Sn nanoparticles into CNFs matrixes can contribute to offer a guide for the application of next-generation SnO 2 -based anodes for energy storage devices.