Delafossite as hole transport layer a new pathway for efficient perovskite-based solar sells: Insight from experimental, DFT and numerical analysis

Herein, we propose a successful technique to produce delafossite materials that can be applied as Hole Transport Layer (HTL) in inorganic lead halide Perovskite solar cells (PSCs). The delafossite CuMO2, where M=Al,Ga,Fe,Cr,Ni,Co,Cr types were investigated the M cation effect on the crystal structure, morphology, and optical properties. These properties were investigated using X-ray, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV visible spectroscopy. The XRD results confirmed their hexagonal and rhombohedral-like structure, where the SEM image of CuMO2 shows the good formation of delafossite layers. The optical band gap of CuMO2 varies from 2.2 eV to 2.99 eV, which is well in line with the literature. Similarly, we also perform the density functional theory (DFT) calculations for delafossite layers to find their electronic properties of them. Based on experimental and DFT calculations, we performed the numerical analysis in SCAPS-1D software on standard solar cell structure (Spiro-OMeTAD/MAPbI3/TiO2) and replaced Spiro-OMeTAD with all the deposited delafossite layers. Our numerical analysis found that HTL shows the highest power conversion efficiency (PCE%) of 22.90. The proposed work can give a good direction for manufacturing to improve the performance of Perovskite-based solar cells (PSCs).