Facile route of heterostructure CeO2-CuO nanocomposite as an efficient electron transport material for perovskite solar cells.

Cerium copper metal nanostructures have received extensive attention as promising electrode materials for energy storage applications due to its attractive structure, and good conductivity. Herein, CeO2-CuO nanocomposite was prepared via chemical method. The crystal structure, dielectric, and magnetic properties of the samples were characterized using by different techniques. The morphological properties of samples were inspected by field emission scanning electron microscopy (FE‒SEM) and high-resolution transmission electron microcopy (HR‒TEM) analysis implied an agglomerated with nanorod structure. The sample surface roughness and morphology were inspected using atomic force microscopy (AFM). Electron paramagnetic resonance (EPR) spectroscopy result reveals the oxygen insufficiency in the material. The variation of oxygen vacancies concentration is consistent with the changes of the saturation magnetization for the sample. Dielectric constant and dielectric losses were studied with respect to the temperature from range from 150 to 350 °C. The electrochemical study of CeO2-CuO nanocomposite shows clear oxidation and reduction peaks with covering wide potential range. In this present paper, first time we have demonstrated that the CeO2-CuO composite as an electron transport material (ETM) with copper (I) thiocyanate (CuSCN) as hole transport material (HTM) for the perovskite solar cells device fabrication. To understand the properties of perovskite like structural, optical, and morphological extensive characterizations such as XRD, UV-visible spectroscopy, and FE-SEM, was performed. For the first time, the CeO2-CuO was used as anode material for preparation low-temperature processing perovskite solar cells, results the power conversion efficiency (PCE) of 10.58% was achieved. The improvement in the device performance for the nanocomposite compared to the pure CeO2, due to unique properties of CeO2-CuO, including high hole mobility, good energy level alignment with CH3NH3PbI3 and longer life time of photo-excited carriers for facilitating the developments of industrial-scale perovskite solar cells.