Evaluating the suitability of tungsten, titanium and stainless steel wires as current collectors in microbial fuel cells.

An appropriate current collector (CC) is crucial for harvesting substantial power in a microbial fuel cell (MFC). In the present study, stainless steel (SS) and titanium wires were used as the CCs for both the anode and cathode of MFC-1 and MFC-2, respectively. Tungsten wire (TW) was used as the anode CC in MFC-3, with SS wire as the cathode CC. In MFC-4, TW was used as the cathode CC with SS wire as the anode CC, and in MFC-5 both electrode CCs were TW. The power density, current density, oxidation current and bio-capacitance were compared to select the best and most cost effective CC material to enhance the power output of MFCs. Maximum power densities (mW/m2 ) of 32.28, 93.10, 225.38, 210.74, and 234.88 were obtained in MFC-1, MFC-2, MFC-3, MFC-4, and MFC-5, respectively. The highest current density (639.86 mA/m2 ) and coulombic efficiency (23.12 ± 1.5%) achieved in MFC-5 showed TW to be the best CC for both electrodes. The maximum oxidation current of 7.4 mA and 7 mA and bio-capacitance of 10.3 mF/cm2 and 9.7 mF/cm2 were achieved in MFC-3 and MFC-5, respectively, suggesting TW is the best as the anode CC and SS wire as the cathode CC to reduce MFC fabrication costs.