Photovoltaics and its magnetic-field promotion effect in dye-sensitized solar cells with BiFeO3 + TiO2 composite photoanodes

Abstract

In dye-sensitized solar cells (DSSCs), the light absorbance of photoanode is the most important factor in power conversion efficiency (PCE). Here the authors report on an alternative modified TiO2-based photoanode for obtaining enhanced photovoltaic (PV) properties in DSSCs. Multiferroics BiFeO3, which possesses excellent magnetic, electric, and photocatalytic performances, was employed to construct BiFeO3 + TiO2 composite photoanode for DSSCs. In this type of DSSCs with BiFeO3 + TiO2 composite photoanodes, BiFeO3 with suitable bandgap may also act as photoelectric conversion medium, which is generally acted by dye in DSSCs, and increases photogenerated carrier transport channels, which improves the PCE of DSSCs with BiFeO3 + TiO2 composite photoanodes. More importantly, magnetic-field enhanced PV properties in abovementioned DSSCs was firstly obtained, which may result from magnetic-field-suppression the recombination of charge carriers and magnetoresistance effect in BiFeO3. The investigated results offer both an alternative method to improve PV properties in DSSCs, and a referential train of thought to manipulate photoelectric properties of solar cells.