| CU2O is acknowledged as a p-type semiconductor, which is caused by the intrinsic Cu vacancies in the Cu2O lattice. Because of its direct band gap of2.14eV and theoretical conversion efficiency of around18%, Cu2O has attracted many researchers’attention in the field of heterojunction and photoelectrochemistry. In addition to these, Cu2O also has low toxicity and good environmental acceptability, is cheap and plentiful, and can be readily prepared as large-area samples.So, as low-cost solar material, Cu2O is a good candidate for heterjunction materials, especially for the top layer semiconductor material for double or there junctions solar cells.Cu2O, with the grains of pyramid shape, which has filling light effect, were prepared by potentiostatic deposition. SEM and XRD were used to characterized the morphology and crystalline structure of deposition layer. The growing process of sulfide layer on the Cu2O and the evolutional process and mechanism of mophology during the photoelectrochemistry stability test were discussed.Besides, ZnO/Cu2O heterojunction solar cell was prepared by potentiostatic deposition, electrochemical workstation, SPS, FISPS and PS were used to investigated the photoelectric conversion properties and the surface photovoltage properties of Cu2O and ZnO/Cu2O heterojunction films. The results show that compared to Cu2O films, the surface photovoltage response of the ZnO/Cu2O heterojunction films have been extended to600-800nm. According to the principle of SPS, FISPS and PS, the extended photovoltage response is ascribed to the transition of deep level in Cu2O which is enhanced by the interfacial electric field between ZnO and Cu2O in the direction from ZnO to Cu2O. The photoinduced electron-hole pair germinates from deep level transition of Cu2O in ZnO/Cu2O heterojunction films can disassociate efficiently by the aid of this strong interfacial electric field. |
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