Tailoring the Boron Configurations in B‐doped Na<sub>3</sub>V<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub>@Carbon for Fast and Durable Sodium Storage
Dong Yan, Shuhao Xiao, Xinyan Li, Rui Wu, Jinxia Jiang, Xiaobin Niu, Jun Song Chen
Abstract
Abstract Na 3 V 2 (PO 4 ) 3 (NVP) is a widely studied cathode material for sodium‐ion batteries because of its high ionic conductivity and attractive charge/discharge plateau (3.4 V vs. Na/Na + ). However, its poor electronic conductivity and severe volume expansion during sodium storage need to be addressed before its intensive application could be realized. Herein, boron‐doped NVP was synthesized through a facile electrospinning method. By adding boric acid into the reaction mixture during electrospinning followed by carbonization, boron could be directly inserted into the carbon matrix, giving rise to B‐doped carbon nanofiber wrapped NVP. By tuning the doping amount, the boron‐containing configurations could be facilely manipulated, playing different roles in promoting the sodium storage properties of the composite. Based on the calculation results, BC 2 O enhanced sodium diffusion by lowering the energy barrier, while BCO 2 improved the structural stability. Due to these specific functionalities of the configurations, the as‐prepared composite with a balanced amount of BC 2 O and BCO 2 demonstrated superior sodium storage capacity of 113 mAh g −1 at 1 C, outstanding long cycling performance of 103 mAh g −1 at 10 C, and retained 91 mAh g −1 after 1500 cycles. This gave rise to a capacity loss of only 0.08‰ per cycle, much better than the undoped counterpart.