Cr2O3/rGO nanocomposite with excellent electrochemical capacitive properties

Abstract

Herein, we have reported the excellent electrochemical capacitive properties of the Cr 2 O 3 /rGO nanocomposite synthesized by hydrothermal. After the structural authentication by Raman spectroscopy and XRD studies, the Cr 2 O 3 /rGO nanocomposite was probed under different physicochemical techniques. It is found that due to good structural congruity between Cr 2 O 3 nanoplates and rGO, the electrochemical properties of Cr 2 O 3 /rGO nanocomposite have strong synergistic effects. As a result, an unprecedented pseudocapacitance of Cr 2 O 3 /rGO nanocomposite is revealed at extremely small scan rate (0.1-1.1 mV s −1). At higher scan rate (10-50 mV s −1), the charge/discharge behavior (in CV) of the Cr 2 O 3 /rGO nanocomposite is found to be oriented towards the ordinary known properties of the commercial Cr 2 O 3 however, the charge storage capacity is still very high. Furthermore, very high theoretical charge storage capacity (93% at 50 mV s −1), high specific capacitance (556 F g −1 /310 F g −1 at 0.75 A g −1 /1.75 A g −1 (GCD) and 635 F g −1 at 1.1 mV s −1 (CV) respectively) and excellent cyclic retention (92% of the initial value after 3500 cycles) was obtained for the Cr 2 O 3 /rGO nanocomposite. The EIS test (Nyquist plot) is in good agreement with the aforementioned results.