Construction of vertically aligned MnCo2O4 needles and Bi2WO6 globules as optimal electrode materials for hybrid supercapacitor
Sanath Kumar, V. Sindhuja, A. Gowdhaman, C. Balaji, R. Ramesh, P.M. Anbarasan
Abstract
A hybrid supercapacitor with high areal energy density device has been formulated and constructed using three-dimensional Bi 2 WO 6 globules and vertically aligned MnCo 2 O 4 nanoneedles grown on Ni-foam current collectors and studied as the negative and positive electrodes. Herein, the novel binder-free Bi 2 WO 6 negative electrode showed the manifest areal capacitance of 1.120 F cm −2 at 1.5 mA cm −2 with a noticeable cycling performance of 77.8% after 1,000 cycles. As well as, the binder-free MnCo 2 O 4 positive electrode showed the superior areal capacitance of 1.281 F cm −2 at 0.75 mA cm −2 with a remarkable cycling response of 93.2% after 10,000 GCD counts. Thus, the more ideal hybrid device with a cell voltage of 1.6 V can deliver a favourable areal energy density of 19.55 μ Wh cm −2 and a maximum power density of 10,000 μ W cm −2 . The improved electrochemical activities of those binder-free electrodes are observed due to the accessibility of huge electrochemically active sites which induces a better electrochemical reaction . These acceptable results demonstrate the assembled hybrid supercapacitor device promoted as a new class of efficient charge storage devices.