Simulation of perovskite solar cells using molybdenum oxide thin films as interfacial layer for enhancing device performance

Organic-inorganic hybrid perovskite solar cells (PSCs) have the issue of interdiffusion at the interfaces that causes undesirable phenomena affecting device efficiency and stability. In this paper, we have investigated MoOx thin films as interlayer between the hole transport material and gold electrode and develop a model using the SCAPS solar cell simulator as a function of the interlayer film thickness to enhance device efficiency and stability. First, different thicknesses (2, 5, 10, 50, and 100 nm) of MoOx films were deposited on glass substrate by electron beam evaporation (e-beam) and their physical, chemical, optical, and electronic properties for PSC were examined. In this research, uniform, homogeneous and pinhole free MoOx films with high transmittance (˃ 80%), very low surface roughness, and resistivity were obtained from the 5 and 10 nm thick samples. In addition, the 10 nm film has shown the lowest photoluminescence emission. Using SCAPS solar cell simulation software and including MoOx thin films as passivation layer, the performance of the PSCs for a Pb-based and Pb-free perovskite absorber were modelled. Results showed that the 10 nm MoOx film is found to provide the best benefit to the device performance with enhanced power conversion efficiency (PCE) of 16.9% and 12.4% for the lead-based MAPb(I1-xBrx)3 and lead-free (MASnI3) perovskite solar cells, respectively.