In Silico Designing of Thieno[2,3- b]thiophene Core-Based Highly Conjugated, Fused-Ring, Near-Infrared Sensitive Non-fullerene Acceptors for Organic Solar Cells

Saleh S Alarfaji; Faiz Rasool; Bushra Iqbal; Ajaz Hussain; Riaz Hussain; Muhammad Akhlaq; Muhammad Fayyaz Ur Rehman

doi:10.1021/acsomega.2c06877

In Silico Designing of Thieno[2,3- b]thiophene Core-Based Highly Conjugated, Fused-Ring, Near-Infrared Sensitive Non-fullerene Acceptors for Organic Solar Cells

ACS Omega. 2023 Jan 27;8(5):4767-4781. doi: 10.1021/acsomega.2c06877. eCollection 2023 Feb 7.

Authors

Saleh S Alarfaji^{1

2}, Faiz Rasool³, Bushra Iqbal⁴, Ajaz Hussain³, Riaz Hussain⁵, Muhammad Akhlaq⁶, Muhammad Fayyaz Ur Rehman⁷

Affiliations

¹ Department of Chemistry, Faculty of Science, King Khalid University, P.O. Box 9004, Abha61413, Saudi Arabia.
² Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha61514, Saudi Arabia.
³ Institute of Chemical Sciences Bahauddin Zakariya University, Multan60800, Pakistan.
⁴ Institute of Chemistry, Khwaja Fareed University of Engineering & Information Technology, Rahim Yar Khan64200, Pakistan.
⁵ Department of Chemistry, Division of Science and Technology, University of Education Lahore, Dera Ghazi Khan54000, Pakistan.
⁶ Faculty of Pharmacy, Gomal University, Dera Ismail Khan29050, Pakistan.
⁷ Department of Chemistry, University of Sargodha, Sargodha40100, Pakistan.

Abstract

The performance of organic solar cells (OSCs) has been improving steadily over the last few years, owing to the optimization of device fabrication, fine-tuning of morphology, and thin-film processing. Thiophene core containing fused ring-type non-fullerene acceptors (NFAs) achieved significant proficiency for highly efficient OSCs. Quantum chemical computations are utilized herein with the motive of suggesting new NIR sensitive, highly efficient low-band gap materials for OSCs. A series of extended conjugated A-π-D-π-A architectured novel fused-ring NFAs (FUIC-1-FUIC-6) containing thieno[2,3-b]thiophene-based donor core are proposed by substituting the end-capped units of synthesized molecule F10IC. Different properties including frontier molecular orbital analysis, density of states analysis, transition density matrix analysis, excitation energy, reorganizational energies of both holes (λ_h) and electrons (λ_e), and open-circuit voltage (V _oc) were performed employing the density functional theory approach. Charge transfer analysis of the best-designed molecule with the donor complex was analyzed to comprehend the efficiency of novel constructed molecules (FUIC-1-FUIC-6) and compared with the reference. End-caped acceptor alteration induces the reduction of the energy gap between HOMO-LUMO (1.88 eV), tunes the energy levels, longer absorption in the visible and near-infrared regions, larger V _oc, smaller reorganizational energies, and binding energy values in designed structures (FUIC-1-FUIC-6) in comparison to reference (FUIC). The designed molecules show the best agreement with the PTBT-T donor polymer blend and cause the highest charge from the HOMO to the LUMO orbital. Our findings predicted that thieno[2,3-b] thiophene-based newly designed molecules would be efficient NFAs with outstanding photovoltaic characteristics and can be used in future applications of OSCs.