Application of synthesized porous graphitic carbon nitride and it's composite as excellent electrocatalysts in microbial fuel cell

The performance of microbial fuel cells (MFCs) consisting of exfoliated porous graphitic carbon nitride (ep-GCN) and its composite with acetylene black (AB) as cathode catalyst is evaluated. The cyclic voltammetry and electrochemical impedance spectroscopy of composite ep-GCN-AB indicated excellent oxygen reduction reaction activity and comparable charge transfer resistance with respect to Pt-C. The absence of X-ray diffraction peak at 2 theta = 13 degrees (corresponding to stacked structure of bulk GCN) indicated reduction in thickness. Four MFCs were operated with simulated wastewater with chemical oxygen demand (COD) of 3000 mg L-1. The maximum power densities of MFC-GAB (14.74 +/- 0.17 W m(-3)), MFC-PAB (15.68 +/- 0.58 W m(-3)) and MFC-G (12.47 +/- 0.30 W m(-3)) using ep-GCN-AB, Pt-C and ep-GCN electrocatalyst, respectively, were 2.6, 2.7 and 2.2 times higher than MFC-AB operated with only acetylene black coated cathode. The investigation demonstrates that ep-GCN and its composites can be utilized as excellent cathode catalysts in MFCs at 20 folds lesser cost than Pt-C. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.