Interface Engineering Towards High Performance Planar Perovskite Solar Cells

Recently,Organic-inorganic halide perovskite solar cells have drawn great attention due to their excellent photoelectric properties,supposing to be a promising technology for the photovoltaic industry.There are several interfaces in the stacked device and the charge transport and recombination process in these interfaces plays a significant influence on the device performance.Interface engineering can effectively improve the interface contact and contribute to the charge transport process.In this thesis,we focus on the interface engineering in the interface between the electron transport layer and the metal electrode as well as the interface between the hole transport layer and the perovskite layer.The main research contents are summarized as follows:1.The organic-inorganic hybrid interfacial layer is adapted to modify the interface between the electron transport layer and the silver electrode.We insert the Bphen:Cs2CO3 layer between the PCBM and the Ag electrode and study the effect on the interface contact and device performance by the morphology and characteristic analysis.Then we optimize the ratio of Cs2CO3(20 wt.%)to achieve the best device performance(17.03%).The study is demonstrated that Bphen:Cs2CO3 is beneficial to the formation of compact interface contact to improve the electron transport and reduce the recombination.2.The organic small molecule is attempted to be the underlayer to modify the interface between the hole transport layer and the perovskite layer.We study the basic characteristics of Rubrene and the condition to fabricate high quality Rubrene film.Then the film is inserted between the PEDOT:PSS layer and the light absorbing layer in perovskite solar cells as the underlayer and the effect on device performance is characterized.The results suggest that Rubrene can effectively passive the interface between the HTL and the perovskite layer.The resulted compact interface contact facilitates the charge transport process.In addition,hydrophobic Rubrene film drives the crystalline grain growth of high quality perovskite.The results indicate that Rubrene contributes to the improvement of device performance.