Asymmetric, efficient π-conjugated organic semiconducting chromophore for bulk-heterojunction organic photovoltaics. (February 2018)

• Record Type: Journal Article
• Authors: Nazim, M.; Ameen, Sadia; Shaheer Akhtar, M.; Shin, Hyung Shik
• Is Part Of: Dyes and pigments. Volume 149(2018)
• Page Start: 141
• Page End: 148
• Publication Date: 2018-02
• Subjects: Benzothiadiazole -- 3, 5-bis (trifluoromethyl) benzene -- Electrochemical properties -- Semiconducting chromophore -- Organic photovoltaics; Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2017.09.048
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: A novel, asymmetric benzothiadiazole-core π-conjugated organic semiconducting chromophore (CF-BTz-ThR) containing an alkyl bithiophene donor and 3, 5-bis (trifluoromethyl) benzene as acceptor unit was synthesized via Suzuki cross-coupling in a relatively cost-effective way. The synthesized chromophore was applied as an acceptor material in the solution-processed fabrication of bulk heterojunction (BHJ) organic photovoltaics (OPVs). The presence of terminal hexyl chain in CF-BTz-ThR induced its solubility in common organic solvents. The energy levels of CF-BTz-ThR were calculated as −5.22 eV and −3.19 eV for HOMO and LUMO, respectively. The fabricated devices attained power conversion efficiency (PCE) of ∼3.52% for CF-BTz-ThR: PC61 BM (1:3, w/w) ratio with the short circuit current (JSC ) of ∼10.38 mA/cm 2 and the open-circuit voltage (VOC ) of ∼0.68 V. The reasonable JSC and VOC of the devices might be attributed to strong absorption and emission properties as well as the electrochemical properties due to the presence of strong electron-withdrawing benzothiadiazole as well as –CF3 unit as electron-acceptor. Highlights: An asymmetric benzothiadiazole-core π-conjugated organic (CF-BTz-ThR) semiconducting chromophore. It is applied as an electron-donor material in the solution-processed organic solar cells. CF-BTz-ThR presents the good HOMO (−5.22 eV) and LUMO (−3.19 eV) values. Device with CF-BTz-ThR:PC61 BM (1:3, w/w) ratio attains reasonable power conversion efficiency (PCE) of ∼3.52%.