Surfactant assisted electrodeposition of MnO2 thin films: Improved supercapacitive properties

Highlights: → Effect of Triton X-100 on physico-chemical properties of MnO2 films. → High supercapacitance of 345 F g-1. → Charge-discharge, impedance spectroscopy. - Abstract: In order to obtain a high specific capacitance, MnO2 thin films have been electrodeposited in the presence of a neutral surfactant (Triton X-100). These films were further characterized by means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM) and contact angle measurement. The XRD studies revealed that the electrodeposited MnO2 films are amorphous and addition of Triton X-100 does not change its amorphous nature. The electrodeposited films of MnO2 in the presence of the Triton X-100 possess greater porosity and hence greater surface area in relation to the films prepared in the absence of the surfactant. Wettability test showed that the MnO2 film becomes superhydrophilic from hydrophilic due to Triton X-100. Supercapacitance properties of MnO2 thin films studied by cyclic voltammetry, galvanostatic charge-discharge cycling and impedance spectroscopy showed maximum supercapacitance for MnO2 films deposited in presence of Triton X-100 is 345 F g-1.