Toward elevated light harvesting: efficient dye-sensitized solar cells with titanium dioxide/silica photoanodes

Abstract

Pursuit of light harvesting is a persistent objective for dye-sensitized solar cells (DSSCs). Here we report the synthesis of titanium dioxide/silica (TiO₂/SiO₂) nanocrystallite photoanodes, aiming at elevating the light harvesting for dye excitation. Due to light interference effect of the reflected light beams from TiO₂/SiO₂ and SiO₂/electrolyte interfaces, the dye excitation and therefore the photocurrent density are markedly enhanced. The photovoltaic performances of the resultant DSSCs are optimized by utilizing three TiO₂/SiO₂ photoanodes from different synthetic strategies. A maximum power conversion efficiency of 8.56% is measured under simulated air mass 1.5 global sunlight in comparison with 7.06% from pristine TiO₂ based DSSC. The high power conversion efficiency in combination with simple preparation demonstrates the potential for utilization of TiO₂/SiO₂ nanocrystallite anodes in efficient DSSCs.