Sarcouncil Journal of Applied Sciences Aims & Scope

Abstract: Hole transport materials (HTMs) play a pivotal role in determining the efficiency, operational stability, and overall performance of both organic and perovskite solar cells. As the demand for high-efficiency and cost-effective solar energy technologies grows, the rational design of HTMs has become increasingly critical. Density Functional Theory (DFT) has emerged as a powerful and predictive computational approach for guiding the molecular design of HTMs, offering insights into critical parameters such as frontier molecular orbital (HOMO-LUMO) energies, reorganization energy, ionization potential, and thermal stability. This review summarizes the theoretical foundation of DFT as applied to HTM development, focusing on widely used functionals (e.g., B3LYP, CAM-B3LYP) and basis sets, and discussing performance descriptors that influence charge transport and film formation. Representative case studies, including benchmark materials such as Spiro-OMeTAD, P3HT, and novel derivatives like P3CPenT, illustrate how DFT can reduce experimental trial-and-error and accelerate the screening of promising candidates. Additionally, the review explores emerging strategies, such as the development of dopant-free HTMs, sustainable and lead-free material systems, and the integration of machine learning with quantum chemical calculations for high-throughput material discovery. These approaches highlight the evolving synergy between computational modeling and experimental synthesis. Overall, DFT continues to be instrumental in the next-generation design of HTMs, offering a roadmap for tailoring molecular properties to meet the stringent demands of modern photovoltaic applications.