Enhancing sustainable bioelectricity generation using facile synthesis of nanostructures of bimetallic Co-Ni at the combined support of halloysite nanotubes and reduced graphene oxide as novel oxygen reduction reaction electrocatalyst in single-chambered microbial fuel cells

The present study aims to utilize the high surface area of the nanotube structure of hal-loysite (HNTs), an aluminosilicate clay, and conductivity of reduced graphene oxide (rGO) as support material for the deposition of nickel (Ni) and cobalt (Co) nanoparticles. With that aim, a novel bimetallic cathode electrocatalyst, Co-Ni @ HNTs-rGO (Catalyst H3), is developed. This catalyst is characterized by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Transmission Electron Microscopy (TEM). Catalyst H3 demonstrates outstanding oxygen reduction reaction (ORR) activity, electro-chemical stability, electrocatalytic performance, and lowest resistance in comparison to the other developed catalysts and conventional Pt/C. Catalyst H3 is used in single -chambered MFCs (microbial fuel cells), where the anode is filled with molasses-laden wastewater. The attained maximum power density in MFC (catalyst H3) is 455 +/- 9 mW/ m2, which is higher than other catalysts. All the results indicate towards its potential use in MFC application. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.