Enhancement in the Photovoltaic Properties of Hole Transport Materials by End-Capped Donor Modifications for Solar Cell Applications

Efficient hole transport materials for solar cell applications are gained huge intension of every scientist. Hole transport materials play a dominant role in solar cells as they provide high power conversion efficiency along with low cost, less toxic, and easy synthesis routs. Motivates from valuable literature, here efforts are being made to designed new novel hole transport materials for solar cell applications. Five new and highly efficient hole transport molecules (BT1-BT5) are designed after end-capped donor modifications of recently synthesized B3 (R) molecule. The photovoltaic, optoelectronic, and structural-property relationship of all designed molecules are extensively studied while using density functional theory and time-dependent density functional theory at MPW1PW91/6-31G(d,p) basis set. Low reorganizational energy of hole is observed in all designed molecules as compared to reference molecule which suggested that designed molecules have high hole mobility as compared to R molecule. Red-shifting in absorption spectrum of designed molecules (as compared to reference molecule) is also seen which offer high power conversion efficiency and high excited highest occupied molecular orbital to lowest unoccupied molecular orbital charge shifting. Low binding and excitation energies are observed in designed molecules. Molecular electrostatic potential, transition density matrix, hole-electron overlap as heat map, open circuit voltage, density of states, and complex study of BT5:PC61BM is also performed for all studied molecule. After all analysis, we believed that our theoretical designed molecules are superior to R molecule, thus we recommend these molecules to experimentalist for future development of highly-efficient solar cells.

Automated summary

Efforts to design novel high-efficient hole transport materials for solar cell applications have been made, resulting in molecules with high hole mobility and red-shifting absorption spectrum. The theoretical designed molecules are believed to be superior to the reference molecule, recommended for future development of highly-efficient solar cells.