Metal-free indoline dye sensitized solar cells based on nanocrystalline Zn2SnO4

Zn2SnO4 nanocrystals were synthesized and first used as the electrode materials for the metal-free indoline dyes sensitized solar cells (DSSCs). The highest efficiency of 3.08% was achieved for a D131 DSSC. This might be attributed to the fact that the D131 dye has a greater positive oxidation potential, which can lead to rapid dye regeneration, avoiding the geminate charge recombination between oxidized dye molecules and injected electrons in the Zn2SnO4 film. The efficiency can be improved significantly using a mixture solution of D131 and N719 dyes for which an efficiency of 3.6% was obtained.