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

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.

SUBMITTER: Park J

PROVIDER: S-EPMC6644754 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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

Park Jihyeon J Kim Sudeok S Lee Gibaek G Choi Jinsub J

ACS omega 20180830 8

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 applica ...[more]

PMID: 31459149

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