Designing of non-fullerene 3D star-shaped acceptors for organic solar cells

• Published in: Journal of molecular modeling 2019-05, Vol.25 (5), p.129-12, Article 129
• Main Authors: Ans, Muhammad, Iqbal, Javed, Eliasson, Bertil, Saif, Muhammad Jawwad, Javed, Hafiz Muhammad Asif, Ayub, Khurshid
• Format: Article
• Language: English
• Subjects: Absorption spectra; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Density functional theory; Density of states; Dichloromethane; Diketopyrrolopyrrole; Doppler effect; Fullerenes; Hole mobility; Malononitrile; Methylene; Molecular Medicine; Molecular orbitals; Non-fullerene acceptor; Open circuit voltages; Optical properties; Organic chemistry; Original Paper; Photovoltaic cells; Red shift; Solar cells; Theoretical and Computational Chemistry; Triphenylamine
• ISSN: 1610-2940; 0948-5023; 0948-5023
• DOI: 10.1007/s00894-019-3992-9

The design and fabrication of solar cells have recently witnessed the exploration of non-fullerene-based acceptor molecules for higher efficiency. In this study, the optical and electronic properties of four new three-dimensional (3D) star-shaped acceptor molecules (M1, M2, M3, and M4) are evaluated for use as acceptor molecules in organic solar cells. These molecules contain a triphenylamine donor core with diketopyrrolopyrrole acceptor arms linked via a thiophene bridge unit. Molecules M1–M4 are characterized by different end-capped acceptor moieties, including 2-(5-methylene-6-oxo-5,6-dihydrocyclopenta-b-thiophen-4-ylidene)malononitrile (M1), 2-(2-methylene-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (M2), 2-(5-methyl-2-methylene-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (M3), and 3-methyl-5-methylnene-thioxothiazolidin-4-one (M4). The properties of the newly designed molecules were compared with a well-known reference compound R, which was recently reported as an excellent acceptor molecule for organic solar cells. Molecules M1–M4 exhibit suitable frontier molecular orbital patterns for charge mobility. M2 shows maximum absorption (λ max ) at 846.8 nm in dichloromethane solvent, which is ideal for the design of transparent solar cells. A strong electron withdrawing end-capped acceptor causes a red shift in absorption spectra. All molecules are excellent for hole mobility due to a lower value of λ h compared to the reference R. Graphical abstract Here, we have designed four new triphenylamine-based three-dimensional star-shaped electron acceptors with different electron withdrawing end-capped acceptor moieties, namely M1 , M2 , M3 , and M4 ) for opto-electronic properties of organic solar cells. The designed star-shaped acceptor molecules show excellent optoelectronic properties with respect to reference compound R .