Stable and Efficient Photoinduced Charge Transfer of MnFe2 O4 /Polyaniline Photoelectrode in Highly Acidic Solution

Tailoring conductive polymers with inorganic photocatalysts, which provide photoinduced electron-hole generation, have significantly enhanced composites leading to excellent photoelec-trodes. In this work, MnFe2 O4 nanoparticles prepared by a hydrothermal method were combined with polyaniline to prepare mixed (hybrid) slurries, which were cast onto flexible FTO to prepare photoelectrodes. The resulting photoelectrodes were characterized by XRD, FESEM, HRTEM and UV-VIS. The photoelectrochemical performance was investigated by linear sweep voltammetry and chronoamperometry. The photocurrent achieved by MnFe2 O4 /Polyaniline was 400 µA/cm2 at 0.8 V vs. Ag/AgCl in Na2 SO4 (pH = 2) at 100 mW/cm2, while polyaniline alone achieved only 25 µA/cm2 under the same conditions. The best MnFe2 O4 /Polyaniline displayed an incident photon-to-current conversion efficiency (IPCE) and applied bias photon-to-current efficiency (ABPE) of 60% at 405 nm wavelength, and 0.17% at 0.8 V vs. Ag/AgCl, respectively. High and stable photoelectrochemical performance was achieved for more than 900 s in an acidic environment.