Polyaniline and sulfonated graphene oxide supported bimetallic manganese cobalt oxides as an effective and non-precious cathode catalyst in air-cathode microbial fuel cells
By Papiya, Farhan; Pattanayak, Prasanta; Biswas, Abul Kalam; Kundu, Patit Paban
Published in Journal of Environmental Chemical Engineering
2021
Abstract
This study examines the feasibility of the use of nanocomposite of polyaniline (PAni) grafted sulfonated graphene oxide (SGO) supported manganese cobalt oxide as a novel and effective cathode catalyst for single chamber microbial fuel cell (SC-MFC). The graphene oxide (GO) was sulfonated to SGO for the development of a significant increase in the hydrophilicity of GO to enhance the nano−catalyst dispersion. The structural properties of the prepared nanocomposite were studied by X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. Morphological studies of the nanocomposite revealed a wrinkled paper−like structure of SGO and a spherical type structure of Mn−Co. Both cyclic voltammetry and electrochemical impedance spectroscopy showed a reduction current value of −1.04 mA, and charge-transfer resistance of 52.4 ohm, which exhibited a higher oxygen reduction reaction activity and good conductivity compared to Mn−Co/GO−PAni, Mn−Co/rGO−PAni and Pt/C catalyst. Electrochemical tests also suggest that the Mn−Co/SGO−PAni nanocomposite exhibited excellent durability among the other three cathodes. Furthermore, the MFCs equipped with Mn−Co/SGO−PAni nanocomposite modified electrode achieved power density of 1392.68 mW m−2 which is 2.89 times higher than state-of-art Pt/C (481.3 mWm−2). The Electrochemical studies also displayed a similar result. The significant increase in power generation with Mn−Co/SGO−PAni nanocomposite as a cathode catalyst indicates that it can be used as a promising, inexpensive electrocatalyst for the long-term operation for MFC.