Facile scalable manufacture of improved electrodes using structured surface coatings of nickel oxide as cathode and reduced graphene oxide as anode for evaluation in a prototype development on microbial fuel cells

Abstract

Improvement of the microbial fuel cell performance is highly required in energy production associated with domestic sewage treatment. For this objective, metal electrodes coated with specific materials for anode and cathode were manufactured. Materials such as reduced graphene oxide (rGO) as an anode, with high electrical conductivity, and structured nickel oxide (sNiO), which act as air cathode, could be the key to obtaining substantial improvements in the production of energy and treatment of domestic sewage. In this work, simple methods were developed to coat the stainless steel meshes with rGO and sNiO, used in MFC prototypes. The results show that the methodologies developed for the coating of the electrodes aid to improve the performance of the MFC in the delivery of potential, current density and power density up to 220%, 140% and 700% respectively, compared to the blank stainless steel electrodes; while the COD levels in the water purified by the MFC with covered electrodes reached a decrease of 36% compared to the same system without covered electrodes. Additionally, the built MFCs prototypes were tested as a power supply for a digital clock and an LED light.