Molecular engineering of indenoindene-3-ethylrodanine acceptors with A2-A1-D-A1-A2 architecture for promising fullerene-free organic solar cells

Author(s)

Khalid, Muhammad ^[1] ; Momina ; Imran, Muhammad ^[2] ; Rehman, Muhammad Fayyaz Ur ^[3] ; Braga, Ataualpa Albert Carmo ^[4] ; Akram, Muhammad Safwan ^{[5, 6]}

Affiliation

^[1] Dept Chem, Rahim Yar Khan 64200 - Pakistan

^[2] King Khalid Univ, Fac Sci, Dept Chem, POB 9004, Abha 61413 - Saudi Arabia

^[3] Univ Sargodha, Inst Chem, Sargodha 40100 - Pakistan

^[4] Univ Sao Paulo, Dept Quim Fundamental, Inst Quim, Av Prof LineuPrestes 748, BR-05508000 Sao Paulo - Brazil

^[5] Teesside Univ, Natl Horizons Ctr, Darlington DL1 1HG, Durham - England

^[6] Teesside Univ, Sch Hlth & Life Sci, Middlesbrough TS1 3BX, Cleveland - England

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 11, n. 1 OCT 13 2021.
• Web of Science Citations: 0

Abstract

Considering the increased demand and potential of photovoltaic devices in clean, renewable electrical and hi-tech applications, non-fullerene acceptor (NFA) chromophores have gained significant attention. Herein, six novel NFA molecules IBRD1-IBRD6 have been designed by structural modification of the terminal moieties from experimentally synthesized A2-A1-D-A1-A2 architecture IBR for better integration in organic solar cells (OSCs). To exploit the electronic, photophysical and photovoltaic behavior, density functional theory/time dependent-density functional theory (DFT/TD-DFT) computations were performed at M06/6-311G(d,p) functional. The geometry, electrical and optical properties of the designed acceptor molecules were compared with reported IBR architecture. Interestingly, a reduction in bandgap (2.528-2.126 eV), with a broader absorption spectrum, was studied in IBR derivatives (2.734 eV). Additionally, frontier molecular orbital findings revealed an excellent transfer of charge from donor to terminal acceptors and the central indenoindene-core was considered responsible for the charge transfer. Among all the chromophores, IBRD3 manifested the lowest energy gap (2.126 eV) with higher lambda(max) at 734 and 745 nm in gaseous phase and solvent (chloroform), respectively due to the strong electron-withdrawing effect of five end-capped cyano groups present on the terminal acceptor. The transition density matrix map revealed an excellent charge transfer from donor to terminal acceptors. Further, to investigate the charge transfer and open-circuit voltage (V-oc), PBDBT donor polymer was blended with acceptor chromophores, and a significant V-oc (0.696-1.854 V) was observed. Intriguingly, all compounds exhibited lower reorganization and binding energy with a higher exciton dissociation in an excited state. This investigation indicates that these designed chromophores can serve as excellent electron acceptor molecules in organic solar cells (OSCs) that make them attractive candidates for the development of scalable and inexpensive optoelectronic devices. (AU)

• FAPESP's process: 11/07895-8 - Theoretical study of the Heck-Matsuda reactions
• Grantee: Ataualpa Albert Carmo Braga
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/01491-3 - Theoretical study of cross-coupling reactions: homogeneous and heterogeneous catalysis
• Grantee: Ataualpa Albert Carmo Braga
• Support Opportunities: Regular Research Grants
• FAPESP's process: 14/25770-6 - New frontiers in cross-coupling reactions promoted by palladium: combining enantioselective catalysis, C-H activations, new materials and in flux reactions aiming at high efficiency and sustainability in synthetic processes
• Grantee: Carlos Roque Duarte Correia
• Support Opportunities: Research Projects - Thematic Grants