A Solution‐Processable Dithienyldiketopyrrolopyrrole Dye Molecule with Acetylene as a π‐Linkage for Organic Solar Cells. Issue 5 (17th March 2015)

• Record Type: Journal Article
• Authors: Wang, Li‐Ping; Xia, Yan; Luo, Guo‐Ping; Zhang, Chun‐Hui; Liu, Quan; Tan, Wan‐Yi; Zhu, Xu‐Hui; Wu, Hong‐Bin; Peng, Junbiao; Cao, Yong
• Is Part Of: Asian journal of organic chemistry. Volume 4:Issue 5(2015:May)
• Page Start: 470
• Page End: 476
• Publication Date: 2015-03-17
• Subjects: Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; 547.005
• DOI: 10.1002/ajoc.201500068
• Languages: English
• ISSNs: 2193-5807

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>We present the efficient synthesis and photovoltaic response of a linearly conjugated molecule <bold>DT‐DPP (AAnAT)₂</bold>, which contains a dithienyldiketopyrrolopyrrole core symmetrically connected through a 9, 10‐anthracenyl unit to 3‐alkylthiophene via an acetylene linkage. The compound is crystalline with a <italic>T</italic>_m of 204 °C. The as‐cast film has a main broad absorption at 650 nm with a shoulder at 737 nm, tailing until ca. 800 nm. The HOMO level was estimated as −5.26 eV, derived from the first reversible electron oxidation wave at ca. 0.93 V vs. Ag/AgCl reference electrode. The space charge limited current hole mobility of a pristine film is ca. 2.90×10⁻⁴ cm² V⁻¹ s⁻¹. The preliminary characterization of simple bulk heterojunction solar cells provides a power conversion efficiency (PCE) of ca. 4.0 % with <italic>V</italic>_OC=0.77 V, <italic>J_SC</italic>=10.0 mA cm⁻², and <italic>FF</italic>=52 %, based on the as‐cast active layer without a processing additive or solvent vapor annealing. Thermal annealing the active layer at a mild temperature of 50 °C increased the PCE to 4.39 % due mainly to the improvement of the <italic>FF</italic>.</p> </abstract>