Electrospun three dimensional TiO2@N/P co-doped carbon nanofibers framework as high-performance anode materials for lithium-ion batteries

Electrospinning combined with heating treatment is employed to fabricate N/P co-doped carbon nanofibers encapsulating homogenous ultrafine TiO2 nanoparticles (TiO2@N/P-CNFs). Characterization results reveal that one-dimensional electrospun composite nanofibers with high electronic conductivity and structural integrity are interconnected with each other to construct a three-dimensional conductive nanofiber network as efficient ion/ electron transport channels. Specifically, the Li//TiO2@N/P-CNFs coin cell delivers an initial discharge specific capacity of 754.9 mAh/g at 100 mA/g and maintains the reversible specific capacity of 486.1 mAh/g after 100 cycles. Moreover, the cell expresses the exceptional rate capability with discharge specific capacity of 272.2 mAh/g at 2000 mA/g, whose capacity can be restored to 474.3 mAh/g as soon as the current density is returned to 100 mAh/g. Furthermore, Li//TiO2@N/P-CNFs cell demonstrates a significant pseudocapacitive contribution of 78% at 1.0 mV/s. The excellent electrochemical performance can be explained by the fact that the N/P codoping strategy is promising strategy for facilitating Li+ ions storage and transfer by broadening interlayer distance and increasing the distribution of defects and active sites. Besides, ultrafine TiO2 nanoparticles with diameter of about 7 nm harness excellent mechanical strength to maintain structural stability upon cycling. Therefore, easily fabricated TiO2@N/P-CNFs composite nanofibers with excellent electrochemical properties may be served as a promising option for advanced anode materials for lithium-ion batteries.