Improving the photovoltaic performance of the all-solid-state TiO₂ NR/CuInS₂ solar cell by hydrogen plasma treatment

The interfacial properties of the heterojunction between p-type and n-type materials play an important role in the performance of the solar cell. In this paper, a p-type CuInS₂ film was deposited on TiO₂ nanorod arrays by spin coating to fabricate an all-solid-state solar cell and the TiO₂ nanorod arrays were treated with hydrogen plasma(H:TiO₂) to ameliorate the interfacial properties. The influence of the hydrogen plasma treatment on the performance of the solar cell was investigated. The short-circuit current density was obviously raised and the power conversion efficiency of the solar cell improved to 0.30%, which is three times that of solar cells without hydrogen plasma treatment. The enhancement of the performance is attributed to not only the enhancement of carrier separation and transport, but the reduction of the recombination of electrons and holes, which is caused by hydrogen plasma treatment. (paper)