Effect of PCBM nanoparticles in Lead-based Layered (PEA)2PbI4 Perovskite Thin Films

Abstract

Two-dimensional (2D) layered halide perovskites are considered to be one of the future potential semiconductor materials due to their higher moisture stability than three-dimensional (3D) perovskites. However, improving this material's optical and electrical properties is still necessary for critical applications. The technique of additive engineering can be utilized to tune and enhance the optoelectrical properties of the 2D perovskites. This work studies the impact of mixing a certain amount of a fullerene derivative ‘[6,6]-phenyl C61-butyric acid methyl ester’ (PCBM) into 2D (PEA)2PbI4 perovskite thin films. Further, the analyses show that PCBM is not affecting the structure and bandgap of the (PEA)2PbI4 perovskite. On the other hand, PCBM improves photoluminescence intensity and enhances the charge separation at the perovskite/PCBM interface. So, even though PCBM can heal certain defect states in the (PEA)2PbI4 perovskite material, the excitons generated over-illumination are separated at the perovskite/PCBM interface and trapped by this fullerene derivative. As a result, the presence of PCBM nanoparticles in (PEA)2PbI4 perovskite thin films reduces the photocurrent generation even though there is an improvement in open circuit potential (Voc). Furthermore, the PCBM nanoparticles decrease the photocatalytic activity of (PEA)2PbI4 perovskite thin films.