Carbon-coated LiTi2(PO4)3 composites synthesized through tannic acid with high rate performance for aqueous lithium-ion batteries

Carbon-coated LiTi2(PO4)3 (LTP-1) was synthesized by sol-gel and in-situ coating method, with tannic acid as carbon source. To compare the electrochemical performance, LTP-2 and LTP-3 were synthesized by the same method with citric acid and lactic acid as carbon sources, respectively. After calcination, the amor-phous carbon layers were coated on the surface of LiTi2(PO4)3 crystal. Carbon contents of all the samples were controlled around 9.0%. The primary particles of LTP-1 are 20-50 nm, which agglomerate into irregular micron-sized secondary particles. The primary particles of LTP-2 and LTP-3 are 60-100 nm. As anode in aqueous lithium-ion batteries (LIBs), LTP-1 presented high cyclic stability and rate performance. The initial discharge capacity of LTP-1 is 60.9 mAhmiddotg-1 at rate of 10 C. After cycling for 1000 cycles, the capacity retention rate of LTP-1 is 72.8%. As for LTP-2 and LTP-3, the initial specific discharge capacity is 46.0 mAhmiddotg-1 and 44.0 mAhmiddotg-1, the corresponding capacity retention rates are 45.4% and 16.4%, respectively, with the same testing parameters.(c) 2023 Elsevier B.V. All rights reserved.

Automated summary

Carbon-coated LiTi2(PO4)3 (LTP-1) was synthesized using sol-gel and in-situ coating method with tannic acid as carbon source. Comparison was made with LTP-2 and LTP-3, synthesized using citric acid and lactic acid as carbon sources, respectively. LTP-1 exhibited high cyclic stability and rate performance as an anode in aqueous lithium-ion batteries, with an initial discharge capacity of 60.9 mAhmiddotg-1 at a rate of 10 C and a capacity retention rate of 72.8% after 1000 cycles. LTP-2 and LTP-3 showed lower initial specific discharge capacities and capacity retention rates under the same testing parameters. (c) 2023 Elsevier B.V. All rights reserved.