ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Modified electrodes based on MnO₂ electrodeposited onto carbon felt: an evaluation toward supercapacitive applications

C. S. Santos, R. D. de Oliveira, Sudhagar Pitchaimuthu, L. F. Marchesi, and C. A. Pessôa

Department of Chemistry, Universidade Estadual de Ponta Grossa, Paraná, Brazil

E-mail: luismarchesi@utfpr.edu.br

Received: 22 March 2019  Accepted: 3 September 2019

Abstract:

This work describes the electrochemical characterization toward supercapacitive properties of a modified electrode based on MnO₂ electrodeposited onto carbon felt electrode (CFE/MnO₂). Raman analysis confirmed the electrode modification and FEG-SEM images showed a 3D network structure with a homogeneous deposit of the MnO₂ film. The morphology of the electrodeposited film showed to be dependent on the electrodeposition applied potential and time. Cyclic voltammetry and galvanostatic charge/discharge curve results showed that the charge storage process is reversible and a combination of EDLC and pseudocapacitive behavior. Under optimized conditions (1.2 V and 600 s), the modified electrode presented a specific capacitance of 541 F g⁻¹ in an applied current density of 0.2 A g⁻¹, which was attributed to a favored accessibility of the electrolyte on the film porous due to morphological issues. Besides, the modified electrode revealed a good capacitance retention of 80% in an applied current density of 1.0 A g⁻¹ after 1000 cycles.

Keywords: Carbon felt; MnO2; Electrodeposition; Supercapacitive properties

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-019-00920-9

Chemical Papers 74 (3) 887–894 (2020)