Raising Lithium Storage Performances of NaTi ₂ (PO ₄ ) ₃ by Nitrogen and Sulfur Dual-Doped Carbon Layer

NaTi ₂ (PO ₄ ) ₃ as anode exhibits promising prospects in aqueous lithium ion battery due to the open frame and good stability. In this paper, N/S dual-doped carbon encapsulated NaTi ₂ (PO ₄ ) ₃ nanoparticle (NTP@CNS) as anode for aqueous lithium ion battery has been successfully fabricated through sol-gel method followed by calcination treatment. Benefiting from the unique carbon layer doped nitrogen and sulfur, NTP@CNS shows excellent electrochemical property. It delivers discharge capacity of 119.4, 101.5, and 84.5 mAh g ⁻¹ at 0.5, 7.0, and 15 C, separately, increasing by 10, 30.5, and 51.2 mAh g ⁻¹ compared to original sample. Moreover, NTP@CNS demonstrates capacity retention of 83.4% after 1000 cycles at 6 C. The excellent property of NTP@CNS is because N/S dual-doping raises electronic conductivity of the sample, and also forms a lot of defects on the electrode surface. This can accelerate Li ion intercalation/deintercalation and electron transfer. N/S dual-doped carbon encapsulation for NaTi ₂ (PO ₄ ) ₃ offers an efficacious and hopeful strategy to ameliorate electrochemical performance of anode.