New acceptor-donor-acceptor-type conjugated molecules bearing naphtho[1,2-b: 5,6-b′]dithiophene and (E)-1,2-di(thiophen-2-yl)ethene and their applications in thin-film transistors and photovoltaic cells

Tae Wan Lee, Dae Hee Lee, Tae Ryang Hong, Jicheol Shin, Min Ju Cho, Dong Hoon Choi

Research output: Contribution to journalArticle

7 Citations (Scopus)


We synthesized new diketopyrrolopyrrole (DPP)-based small molecules i.e., TVT(DPP)<inf>2</inf> and NDT(DPP)<inf>2</inf>, containing (E)-1,2-di(thiophen-2-yl)ethene and naphtho[1,2-b:5,6-b′]dithiophene, respectively, as electron-donating moieties with almost identical conjugation lengths. To study the effect of the conjugation bridge between the DPP units on the performance of thin-film transistors (TFTs) and photovoltaic (PV) devices, we performed theoretical calculations and investigated the photophysical and electrochemical properties. Finally, TFTs and PV devices were fabricated, and their charge carrier mobilities and power conversion efficiencies (PCEs) with [6,6]-phenyl-C61-butyric acid methyl ester (PC<inf>61</inf>BM) were measured. The hole mobility of TVT(DPP)<inf>2</inf> was found to be larger than that of NDT(DPP)<inf>2</inf>. The solution-processed bulk-heterojunction PV devices based on TVT(DPP)<inf>2</inf> and NDT(DPP)<inf>2</inf> gave maximum PCEs of 2.21% and 3.03%, respectively.

Original languageEnglish
Pages (from-to)24-32
Number of pages9
JournalSynthetic Metals
Publication statusPublished - 2015 May 16



  • Carrier mobility
  • Conjugated molecule
  • Diketopyrrolopyrrole
  • Photovoltaic cell
  • Thin film transistor

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Chemistry
  • Metals and Alloys
  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

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