Structure–photovoltaic performance relationships for DSSC sensitizers having heterocyclic and benzene spacers

Abstract

Five new sensitizers based on different spacer groups were designed and synthesized in order to facilitate investigation of the effects of heterocyclic spacers on photovoltaic parameters in DSSCs. It was found that generic issues arising from the electronic nature of heterocyclic units affected voltage parameters, with DP-P giving the highest voltage. On the other hand, higher electron transfer yield across a wide range of the solar spectrum played an important role in enhanced current densities. Best performance was achieved by the thiophene based sensitizer DP-T, resulting in an efficiency of 3.5% with J_sc = 8.19 mA cm⁻², V_oc = 0.618 V, ff = 0.697.