Study On Hybrid Solar Cells Based On Hierarchical Shell-Core ZnO Micro-nanostructure

In this paper,well aligned one-dimensional ZnO nanorod arrays and nanosheet arrays were fabricated on indium doped tin oxide coated conducting glass?ITO?substrate by electrochemical method.Then,hierarchical structure of ZnO nanorods on the nanorods and hierarchical structure of ZnO nanorods on the nanosheets arrays were produced by using secdonary electrodeposition.Shell-core Sb₂S₃/ZnO nanostructures were prepared from ZnO nanorods?ZnO nanosheets?ZnO nanorods on nanorods and ZnO nanorods on nanosheets by chemical bath deposition.Then a thin P3HT layer was spin-coted onto the Sb₂S₃/ZnO shell-core structure and ZnO nanostructure arrays,a three-component P3HT/ Sb₂S₃/ZnO composite films and a P3HT/ZnO composite films were obtained.The composition?morphology and structure of electrode materials were investigated by means of SEM?XRD?HRTEM and UV-visible diffuse reflection spectrum.Photovoltaic properties of solar cells based on different electrode materials were also studied.Electrodes based on ZnO nanosheets?ZnO nanorods on nanosheets?Sb₂S₃/ZnO nanosheets and Sb₂S₃/ZnO nanorods on nanosheets were assembled respectively with platinized ITO counter electrodes to fabricate different kinds of hybrid solar cells.The studies showed that a hexagonal wurtzite structure of ZnO and stibnite structure of Sb₂S₃ were prepared.Among them,the diameter of ZnO nanorods was from 200 nm to 300 nm and the length was approximately 2 ?m;The diameter of ZnO nanorods grown on the nanorods was 10-50 nm and the length was about 200 nm;The thickness of ZnO nanosheet was about 80 nm and the height was about 4-5 ?m;The diameter of ZnO nanorods grown on the nanosheets was about 200 nm and the length was about 800 nm.Different Sb₂S₃ nanodendrite shell thickness could be obtained by adjusting the temperature and times,and the best deposition temperature and times were 10 ?and 2 hours,respectively.Sb₂S₃ nanocrystalline has a good light absorption capability and has broadened the absorption spectra of ZnO to 760 nm.When P3HT was spin-coated onto Sb₂S₃/ZnO electrode,photovoltaic properties of solar cells based on P3HT/Sb₂S₃/ZnO electrode was improved greatly.The P3HT/Sb₂S₃/ZnO hierarchical electrode exhibited an energy conversion efficiency as high as 0.81%,which was the highest among all the devices.