A Solution‐Processable Small Molecule Based on Benzodithiophene and Diketopyrrolopyrrole for High‐Performance Organic Solar Cells

Abstract

A linear solution‐processable small molecule (BDT‐2DPP) based on 5‐alkylthiophene‐2‐yl‐substituted benzodithiophene and diketopyrrolopyrrole is designed and synthesized. BDT‐2DPP exhibits strong and broad absorption with low band gap, low lying energy levels matching with PC61BM and high hole mobility. Solution‐processed organic solar cells based on BDT‐2DPP:PC61BM blend showed power conversion efficiencies as high as 5.79%.

A star-shaped D–π–A small molecule based on a tris(2-methoxyphenyl)amine core for highly efficient solution-processed organic solar cells

“…13 C NMR spectra were recorded on a Bruker DRX500 at a frequency of 125 MHz. In the case of 1 H NMR spectroscopy, the compounds to be analysed were taken in the form of 1% solutions in CDCl 3 .…”

“…In the case of 1 H NMR spectroscopy, the compounds to be analysed were taken in the form of 1% solutions in CDCl 3 . In the case of 13 C NMR spectroscopy, the compounds to be analysed were taken in the form of 5% solutions in CDCl 3 . The spectra were then processed on the computer using the ACD Labs soware.…”

“…[4][5][6] The current research pursuits for small molecule-based OSCs target even higher efficiencies by designing and synthesizing new organic small molecules, such as star-or X-shaped molecules and [7][8][9][10] one-or two-dimensional oligomers with D-A-D or A-D-A structures. 3,[11][12][13][14][15][16] In particular, the most promising organic small molecule donor materials for photovoltaic applications are normally built by connecting various electron donating (donor) and electron capturing (acceptor) moieties through a p-conjugating spacer (D-p-A). [7][8][9][11][12][13][14][15][16] Such a D-p-A structure can be used to lower the optical band gap to broaden molecular optical absorption and to assist the formation of favorable morphologies for high photovoltaic performance.…”

“…3,[11][12][13][14][15][16] In particular, the most promising organic small molecule donor materials for photovoltaic applications are normally built by connecting various electron donating (donor) and electron capturing (acceptor) moieties through a p-conjugating spacer (D-p-A). [7][8][9][11][12][13][14][15][16] Such a D-p-A structure can be used to lower the optical band gap to broaden molecular optical absorption and to assist the formation of favorable morphologies for high photovoltaic performance. 17 A large number of D-p-A small molecules have been extensively studied and exhibit considerable molecular photovoltaic properties.…”

4H-1,2,6-Thiadiazin-4-one-containing small molecule donors and additive effects on their performance in solution-processed organic solar cells

“…17 Devices employing solution-processed small molecules as both donor and acceptor components gave device efficiencies of $3%, 18 which is similar to the average device performance of the widely studied and extensively optimized polymer : fullerene P3HT : PC60BM system. 19 As a result of this progress, a wide variety of new small molecules for solutionprocessed organic photovoltaics are being prepared, [20][21][22][23][24] including efficient donor-acceptor-donor (D-A-D) systems. 25 A recent electrochemical study of non-oxidised 4H-1,2,6-thiadiazines indicated electron affinities (LUMO energy values) of À3.25 to À3.66 eV with reversible oxidations and reductions.…”