Power generation in a bio-photoelectrochemical cell with NiTiO3 as a cathodic photocatalyst

Abstract In this study, nickel (II) titanate (NiTiO3), a perovskite-type semiconductor, is investigated as a member of a new generation of cathodic photocatalysts in a dual-chamber microbial fuel cell (MFC). To characterize the synthesized photocatalyst XRD, XPS, SEM, EDX, DLS, and DRS analyses are used. NiTiO3 is deposited on a graphite plate and used as the cathode electrode of a dual-chamber MFC system. To evaluate the photoelectrochemical behavior of the prepared cathode, the LSV and EIS analyses are performed under light irradiation and dark conditions. The MFC equipped with NiTiO3-modified cathode under the visible light irradiation produces the maximum power density and short-circuit current density of 76.86 mW m−2 and 750 mA m−2, respectively. The obtained results are almost twofold and fivefold of the obtained values for the MFC with NiTiO3-modified cathode in the dark condition and the MFC with bare graphite cathode, respectively. Moreover, based on the EIS results, the charge transfer resistance of the cathode decreases from 38.67 Ω in the dark condition to 31.42 Ω under the visible light irradiation due to the improved photoelectrochemical behavior of the cathode. The results reveal the stability of the produced voltage of the MFC as a consequence of the presence of NiTiO3.