DFT-Computational Modeling and TiberCAD Frameworks for Photovoltaic Performance Investigation of Copper-Based 2D Hybrid Perovskite Solar Absorbers.

In this work, we use a combination of dispersion-corrected density functional theory (DFT-D3) and the TiberCAD framework for the first time to investigate a newly designed and synthesized class of (CHN)[CuCl] 2D-type perovskite. The inter- and intra-atomic reorganization in the crystal packing and the type of interaction forming in the active area have been discussed via Hirshfeld surface (HS) analyses. A distinct charge transfer from CuCl to [CHN] is identified by frontier molecular orbitals (FMOs) and density of states (DOS). This newly designed narrow-band gap small-molecule perovskite, with an energy gap ( ) of 2.11 eV, exhibits a higher fill factor (FF = 81.34%), leading to an open-circuit voltage ( ) of 1.738 V and a power conversion efficiency (PCE) approaching ∼10.20%. The interaction between a donor (D) and an acceptor (A) results in a charge transfer complex (CT) through the formation of hydrogen bonds (Cl-H), as revealed by QTAIM analysis. These findings were further supported by 2D-LOL and 3D-ELF analyses by visualizing excess electrons surrounding the acceptor entity. Finally, we performed numerical simulations of solar cell structures using TiberCAD software.