Performance of CeO₂–TiO₂-admixed photoelectrode for natural dye-sensitized solar cell

Abstract

Extracts from roots of Beta vulgaris were used as natural sensitizers of a wide-bandgap semiconductor (CeO₂–TiO₂) in photoelectrochemical solar cells. The natural dye, adsorbed onto the semiconductor surface, absorbs visible light and promotes electron transfer across the dye/semiconductor interface. We have applied CeO₂–TiO₂ to natural dye sensitizer solar cells as a photoelectrode to reduce the charge recombination rate by providing energy barrier at the interface between the photoanode and electrolyte which offers an improvement of photovoltaic efficiency. Short-circuit current density (J _sc) and open-circuit voltages (V _oc) of 9.0 mA cm⁻² and 680 mV, respectively, were obtained, and an effective energy conversion efficiency of 3.5 % was achieved. This simple and cheap technique of cell preparation opens up a perspective of commercial feasibility for inexpensive and environment-friendly dye cells.