High performance supercapattery with rGO/TiO2 nanocomposites anode and activated carbon cathode

Abstract

A hybrid material of reduced graphene oxide/titanium dioxide (rGO/TiO2)was successfully synthesized by facile hydrothermal technique. A different amount of GO ratios at 5%, 10%, 20%, and 30% were loaded with TiO2. It is a well-known fact that porous structure and crystallinity of resultant rGO/TiO2 play a crucial role in synergistic effect which facilitate electron transfer movement and reduce the volume changes during a charge-discharge cycle process. Based on the results obtained, an optimum of 10 wt % GO loading with TiO2 nanocrystals revealed that electrochemical performance achieved the highest specific capacity of 116.70 mAh/g with 0.2 A g−1 among samples. This result inferred that high efficiency of ion diffusion was obtained with low charge transfer resistance between TiO2 nanocrystals and rGO. The supercapattery was assembled in a configuration of optimized 10% rGO/TiO2 nanocomposites as anode while activated carbon as cathode. The result obtained a superior energy density of 54.37 Wh kg−1 at power density of 420.48 W kg−1. Additionally, the specific capacity still remained at 92% for 3000 charging-discharging cycles under a current density of 1 A g−1; hence, good life cycle stability, high specific capacity and low charge transfer resistance of rGO/TiO2 nanocomposites electrode suggested that the prepared materials was a promising anode material for supercapattery application. © 2019 Elsevier B.V.