New efficient tert-butyldiphenyl-4H-pyranylidene sensitizers for DSSCs†
Abstract
Three new triarylamine-free sensitizers for DSSCs containing a tert-butyldiphenyl-4H-pyranylidene as the donor unit are reported. Devices have been carefully optimized resulting in high Jsc values. An efficiency of 5.80% has been obtained for a sensitizer with a thiophene ring in the π spacer. Solvent, dipping time, thickness and photoanode structure have been optimized.