Synthesis and photovoltaic property of fine and uniform Zn ₂SnO ₄ nanoparticles

Zn ₂SnO ₄ nanoparticles (NPs) with a narrow size distribution were synthesized by a simple hydrothermal route by controlling the crystallization process. The average size of NPs was 8 nm, and this was attributed to the formation of a hydroxy carbonate compound as an intermediate phase, which was demonstrated by the structural and elemental analyses. The fine size and visible-transparency of the synthesized NPs enabled the fabrication of transparent films for efficient photoelectrochemical devices. In particular, we demonstrated dye-sensitized solar cells (DSSCs) employing these transparent Zn ₂SnO ₄ photoelectrodes with a high energy conversion efficiency of 4.7%, which is mainly due to an improvement of light harvesting property.