Improvement of photoresponse in an isatin hydrazone/CdTe hybrid heterostructure device via ZnO chelation for photovoltaic applications

摘要

In the present study, a new approach for obtaining a new isatin hydrazone (IL) dye has been carried out. Two types of hybrid inorganic/organic heterojunctions based on CdTe/IL and CdTe/ZnOIL have been fabricated using IL and ZnOIL nano thin films. The impedance spectroscopy technique was used to compare FTO/CdTe/IL/Al and FTO/CdTe/ZnOIL/Al heterojunctions by applying different AC frequencies (42 Hz-5 MHz) and under different light irradiance intensities (0-90 kLux). Besides, the AC electrical properties of the fabricated heterojunctions were examined and compared with each other. The results showed that the fabricated device based on ZnOIL organic interfacial film reveals better electrical characteristics than that based on IL ligand. The enhancement of photoconductive and carrier lifetime in the hybrid system of FTO/CdTe/ZnOIL/Al is correlated with the formation of ZnOIL charge transfer in the ZnO-complex demonstrated by impedance spectroscopy analysis. The obtained result and the comparative study is drawn in the present work supply a new direction for improving the performance of the CdTe solar cells-based IL and ZnOIL interfacial organic layers.