Solution-Processable Low-Molecular Weight Extended Arylacetylenes: Versatile p-Type Semiconductors for Field-Effect Transistors and Bulk Heterojunction Solar Cells

Abstract

We report the synthesis and characterization of a series of five extended arylacetylenes, 9,10-bis-{[m,p-bis(hexyloxy)phenyl]ethynyl}-anthracene (A-P6t, 1), 9,10-bis-[(p-{[m,p-bis(hexyloxy) phenyl]ethynyl}phenyl)ethynyl]-anthracene (PA-P6t, 2), 4,7-bis-{[m,p-bis(hexyloxy)phenyl]ethynyl}-2,1,3-benzothiadiazole (BTZ-P6t, 5), 4,7-bis(5-{[m,p-bis(hexyloxy)phenyl]ethynyl}thien-2-yl)-2,1,3-benzothiadiazole (TBTZ-P6t, 6), and 7,7'-({[m,p-bis(hexyloxy)phenyl]ethynyl}-2,1,3-benzothiadiazol-4,4'-ethynyl)-2,5-thiophene (BTZT-P6t, 7), and two arylvinylenes, 9,10-bis-{(E)-[m,p-bis(hexyloxy)phenyl]vinyl}-anthracene (A-P6d, 3), 9,10-bis-[(E)-(p-{(E)-[m,p-bis(hexyloxy)phenyl]vinyl}phenyl)vinyl]-anthracene (PA-P6d, 4). Trends in optical absorption spectra and electrochemical redox processes are first described. Next, the thin-film microstructures and morphologies of films deposited from solution under various conditions are investigated, and organic field-effect transistors (OFETs) and bulk heterojunction photovoltaic (OPV) cells fabricated. We find that substituting acetylenic for olefinic linkers on the molecular cores significantly enhances device performance. OFET measurements reveal that all seven of the semiconductors are FET-active and, depending on the backbone architecture, the arylacetylenes exhibit good p-type mobilities (mu up to approximately 0.1 cm(2) V(-1) s(-1)) when optimum film microstructural order is achieved. OPV cells using [6,6]-phenyl C(61)-butyric acid methyl ester (PCBM) as the electron acceptor exhibit power conversion efficiencies (PCEs) up to 1.3% under a simulated AM 1.5 solar irradiation of 100 mW/cm(2). These results demonstrate that arylacetylenes are promising hole-transport materials for p-channel OFETs and promising donors for organic solar cells applications. A direct correlation between OFET arylacetylene hole mobility and OPV performance is identified and analyzed.

π-Linkage effect of push-pull-structure organic small molecules for photovoltaic application

“…Besides, OSMs will receive high V OC which were benefited from the deep-lying HOMO level caused by the electron-withdrawing effect of alkyne. Hence, alkyne including acetylene and arylacetylenes is a promising class of π-bridge [78][79][80][81][82][83]. Fig.…”

Donor-π-Acceptor Type Diphenylaminothiophenyl Anthracene-mediated Organic Photosensitizers for Dye-sensitized Solar Cells

“…[21][22][23][24] Even though the anthracene containing compounds have been developed successfully for applications to light-emitting diodes, [25][26][27] thin film transistors, [28][29][30] and bulk heterojunction solar cells 31 not much attempts was made to develop novel photosensitizers for fabricating high performance DSSC. Simple anthracenemediated photosensitizers have been recently reported for DSSCs.…”

Novel Organic Sensitizers Containing 2,6-Difunctionalized Anthracene Unit for Dye Sensitized Solar Cells

“…Among rigid fused aromatic entities, anthracene has been widely used in opto-electronic materials such as organic thin film transistors [22][23][24], organic light-emiting diodes [25][26][27][28][29][30] and bulk heterojunction solar cells [31]. Recently, a few anthracene-based derivatives have been reported as sensitizers for DSSCs [32][33][34].…”