Correlation between Photoinduced Electron Transfer and Photovoltaic Characteristics in Solar Cells Based on Hybrid Core—Shell Nanoparticles

摘要

We study the correlation between photoinduced electron transfer and performance of photovoltaic devices. We have considered hybrid core—shell nanoparticles, where such an electron transfer occurs from an inorganic core to an organic shell layer. From photoluminescence (PL) quenching and decrease in PL lifetime, we find that the rate of photoinduced electron transfer depends on the electron-accepting nature of the organic xanthene molecule on the shell layer. Devices based on such hybrid nanoparticles with CdS in the core and different dye molecules on the shell exhibit photovoltaic characteristics. We find that photoinduced electron transfer leads to exciton dissociation followed by photocurrent in the external circuit of the devices. Short-circuit current of the devices depends on the degree of electron transfer. We report a one-to-one correlation between external quantum efficiency of photovoltaic devices and rate of photoinduced electron transfer in hybrid core-shell nanoparticles.