Hole transport materials (HTMs) play a dominant role in enhancing the photovoltaic and optoelectronic properties of solar cells. These materials efficiently transport the hole that significantly boosts up the power conversion efficiencies of solar cells. With a motive to obtain better photovoltaic materials with efficient optoelectronic characteristics, we have theoretically designed five new hole transport materials (Y3D1-Y3D5) after end-capped donor modifications of recently synthesized highly efficient hole transport material Y3N (R). The relationship between photovoltaic, photophysical, optoelectronic and structural property of these newly designed molecules is extensively examined at MPW1PW91/6-31G(d,p) level of density functional theory (DFT) and time dependent functional theory (TDDFT). For all the studied molecules, geometric parameters like the position of frontier molecular orbitals (FMOs) on the basis of optical properties, open-circuit voltage (Voc), binding energies and density of state (DOS) analysis are performed. Low reorganization energy (RE) results in high load mobility for the hole and electron. As compared to the reference molecule, our engineered donor molecules convey high load mobility. Red shift with low excitation energies and dominant transitions from HOMO to LUMO have been noticed in the absorption spectrum of these engineered molecules. The successful construction of new molecules has been supported by molecular electrostatic potential (MEP). Finally, Y3D3:PC61BM complex is also examined in order to understand the charge transfer in the complex and superposition of orbitals. All analyses indicate that the designed and reported molecules are superior to Y3N molecule, thus we recommend these molecules to experimentalists for future development of highly-efficient solar cells.

Synergistic effect of different end-capped units on the photovoltaic properties of hole transport materials for solar cell applications

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.