RGO-Coated TiO2 Microcones for High-Rate Lithium-Ion Batteries

Jihyeon Park; Sudeok Kim; Gibaek Lee; Jinsub Choi

doi:10.1021/acsomega.8b00926

RGO-Coated TiO₂ Microcones for High-Rate Lithium-Ion Batteries

ACS Omega. 2018 Aug 30;3(8):10205-10210. doi: 10.1021/acsomega.8b00926. eCollection 2018 Aug 31.

Authors

Jihyeon Park¹, Sudeok Kim¹, Gibaek Lee², Jinsub Choi¹

Affiliations

¹ Department of Chemistry and Chemical Engineering, Inha University, 22212 Incheon, South Korea.
² School of Chemical Engineering, Yeungnam University, 38541 Gyeongsan, South Korea.

Abstract

Reduced graphene oxide (RGO)-coated TiO₂ microcones have been synthesized via simple anodization and cyclic voltammetry for use in lithium-ion batteries (LIBs). Microcones had a perpendicularly oriented hollow core, an anatase structure, and a high surface area, allowing higher capacity than other nanosized TiO₂ structures. TiO₂ has low electrical conductivity, leading to the limitation of fast charging and high capacity; however, this was improved by the application of an RGO coating in this work. As anode materials of LIB, the obtained RGO microcone showed a capacity of 157 mAh g^-1 at 10C (fully charged within ∼360 s) and sustained 1000 cycles with only 0.02% capacity fading per cycle. The capacity was 1.5 times higher than that of conventional microcone. We speculated that the decrease in the charge-transfer resistance (R _ct) played a crucial role in increasing the capacity with fast charging.