Design of donor–acceptor–donor (D–A–D) type small molecule donor materials with efficient photovoltaic parameters. Issue 10 (25th February 2017)

• Record Type: Journal Article
• Authors: Irfan, Muhammad; Iqbal, Javed; Sadaf, Sana; Eliasson, Bertil; Rana, Usman Ali; Ud‐din Khan, Salah; Ayub, Khurshid
• Is Part Of: International journal of quantum chemistry. Volume 117:Issue 10(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-02-25
• Subjects: CAM‐B3LYP -- donor -- frontier molecular orbital -- organic solar cell -- thiazolothiazole -- thiophene -- triphenylamine; Quantum chemistry -- Periodicals; 541.28
• DOI: 10.1002/qua.25363
• Languages: English
• ISSNs: 0020-7608

Abstract

Abstract: Four Donor–Acceptor–Donor (D–A–D) type of donor molecules (M1‐M4) with triphenylamine (TPA) as donor moiety, thiophene as bridge, and thiazolothiazole as acceptor unit were designed and its photovoltaic parameters were equated with reference molecule "R." DFT functional CAM‐B3LYP/6‐31G (d, p) was found best for geometry optimization and TD‐CAM‐B3LYP/6‐31G (d, p) was found suitable for excited state calculations. Among designed donor molecules, M4 manifests suitable lowest band gap of 4.73 eV, frontier molecular orbital energy levels as well as distinctive broad absorption of 455.3 nm due to the stronger electron withdrawing group. The electron‐withdrawing substituents contribute to red shifts of absorption spectra and better stabilities for designed molecules. The theoretically determined reorganization energies of designed donor molecules suggested excellent charge mobility property. The lower λ e values in comparison with λ h illustrated that these four donor materials would be ideal for electron transfer and M4 would be best amongst the investigated molecules with lowest λ e of 0.0177. Furthermore, the calculated V oc of M4 is 2.04 V with respect to PC60 BM (phenyl‐C61‐butyric acid methyl ester). This study revealed that the designed donor materials are suitable and recommended for high performance organic solar cell devices. Abstract : Four Donor–Acceptor–Donor (D–A–D) type molecules with triphenylamine as donor moiety, thiophene as bridge, and thiazolothiazole as acceptor unit were computationally designed. All the designed molecules have excellent photovoltaic parameters with respect to reference molecule "R" but among designed donor molecules, one manifests lowest band gap, frontier molecular orbital energy levels, and distinctive broad due to stronger electron withdrawing groups. Such substituents contribute to the red shifts of absorption spectra and better stabilities for designed molecules.