Candle soot-derived carbon nanoparticles: An inexpensive and efficient electrode for microbial fuel cells

Carbon nanoparticles (CNPs) derived from candle soot were used to prepare an efficient electrode of a microbial fuel cell (MFC). The candle soot were deposited on an ultrafine stainless steel (SS) wire disk, and the SS disk-supported CNPs were directly used as the electrodes. The physico-electro-chemical characterization tests showed the prepared electrode materials to be hierarchically porous, graphitic, and mechanically and electrochemically stable. The polarization studies using linear sweep voltammetry analysis revealed the maximum open circuit potential, power and current densities of the fabricated MFC to be 0.68 ± 0.03 V, 1650 ± 50 mW/m2 and 7135 ± 110 mA/m2 respectively. The method of preparation for the soot-derived CNP-based electrode material is simple, cost-effective, reproducible, and scalable, and the fabricated MFC has potential for producing high bioenergy. [Display omitted] •Successful fabrication of MFC electrodes from the CNPs generated from candle soot.•The graphitic CNPs facilitated electron transfer at the electrode surface.•High OCP (0.68 V) and power density (1650 mW/m2) produced using the DCMFC.