Oligothiophene‐Bridged Bis(arylene ethynylene) Small Molecules for Solution‐Processible Organic Solar Cells with High Open‐Circuit Voltage. Issue 8 (6th May 2013)

• Record Type: Journal Article
• Authors: Liu, Qian; Zhan, Hongmei; Ho, Cheuk‐Lam; Dai, Feng‐Rong; Fu, Yingying; Xie, Zhiyuan; Wang, Lixiang; Li, Jin‐Hua; Yan, Feng; Huang, Shu‐Ping; Wong, Wai‐Yeung
• Is Part Of: Chemistry, an Asian journal. Volume 8:Issue 8(2013:Aug.)
• Page Start: 1892
• Page End: 1900
• Publication Date: 2013-05-06
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1002/asia.201300244
• Languages: English
• ISSNs: 1861-4728

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>A new series of conjugated oligothiophene‐bridged bis(arylene ethynylene) small molecules have been designed, synthesized, and characterized by photophysical, electrochemical and computational methods. These compounds were found to have optimal LUMO levels that ensure effective <named-content id="d280e640" content-type="chemicalTechnology" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">charge transfer</named-content> from these compounds to [6, 6]‐phenyl‐C<sub>71</sub>‐butyric acid methyl ester (PC<sub>70</sub>BM). They were utilized as good electron‐donor materials that can be blended with electron‐acceptor PC<sub>70</sub>BM in the fabrication of solution‐processed molecular bulk heterojunction (BHJ) <named-content id="d280e652" content-type="chemicalTechnology" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">solar cells</named-content>. All of these BHJ devices showed very high open‐circuit voltage (<italic>V</italic><sub>oc</sub>) of 0.90–0.97 V, and the best power conversion efficiency achieved was 3.68 %. The high <italic>V</italic><sub>oc</sub> is consistent with the deeper low‐lying HOMO level and is relatively insensitive to the donor : acceptor blend ratio. The spin‐coated <named-content id="d280e666" content-type="chemicalTechnology" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">thin films</named-content> of these small molecules showed p‐channel field‐effect <named-content id="d280e669" content-type="chemicalTechnology" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">charge transport</named-content> with the hole mobilities of up to 2.04×10<sup>−4</sup> cm<sup>2</sup> V<sup>−1</sup> s<sup>−1</sup>. These compounds illuminate the potential of solution‐processible small‐molecular aryl acetylide compounds for efficient <named-content id="d280e685" content-type="chemicalTechnology" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink">power generation</named-content> in photovoltaic implementation.</p> </abstract>