Synergistic effect of TiO2 nanostructured cathode in microbial fuel cell for bioelectricity enhancement

Abstract

Nano-bedecking of electrode with nanoparticles is an effective method to improve power generation of microbial fuel cells (MFCs). In this study, different concentrations (0.25 mg cm?2, 0.50 mg cm?2, 0.75 mg cm?2 and 1.0 mg cm?2) of TiO2 nanoparticles of size 10�25 nm were overlaid on the carbon cloth (CC) using spray pyrolysis technique and used as catalytic cathode in a dual-chambered microbial fuel cell treating distillery wastewater. Results evidenced that TiO2 nanoparticles modified cathode increased the power generation and recorded a highest power and current density of 162.5 � 2 mW m?2 and 1.4 � 0.005 A m?2, respectively. Carbon cloth coated with 0.50 mg cm?2 TiO2 nanoparticles showed 2.8 and 7.3 times higher current and power density as compared to uncoated cathode. MFC operated at a hydraulic retention time (HRT) and organic loading rate (OLR) of 72 h and 59.2 g COD L?1 d?1 showed a maximum chemical oxygen demand (COD) removal of 72.3% which was 15.3% higher than the control MFC. Likewise, the coulombic efficiency of control and modified MFC was 33% and 44%, respectively. The maximum NO3?- N, NO2?- N and NH4+- N removal efficiency of 77.3%, 49.9% and 59.4% were observed for TiO2 nanoparticles modified electrode which was 19.3%, 11.4% and 10.5% higher than control. TiO2 modified cathode was effective in enhancing the bioelectricity generation in MFCs. � 2023