Recent Progress of Benzodifuran‐Based Polymer Donors for High‐Performance Organic Photovoltaics

Abstract

At present, a variety of benzo[1,2‐b:4,5‐b′]dithiophene (BDT)‐based polymer donors are designed and synthesized, which have made great progress toward achieving high power conversion efficiencies (PCEs) of polymer solar cells (PSCs). Despite many advantages of benzo[1,2‐b:4,5‐b′]difuran (BDF) compared with BDT unit, the overall performance of BDF polymer‐based PSCs lags far behind that of the counterpart BDT‐based polymers. Recently, great advances have been achieved in BDF polymer‐based PSCs with the highest PCEs over 16%, suggesting that BDF‐based polymers have the significant potential to catch up or even surpass the performance of BDT‐based polymers. In this review, the recent advances of BDF polymers in PSCs are first summarized and then the design strategies and the chemical structure–performance relationships of BDF polymers are discussed. Finally, perspectives on the future development of BDF polymers for high‐efficiency PSCs are provided.

Two-dimensional benzo[1,2-b : 4,5-b′]difurans as donor building blocks for the formation of novel donor–acceptor copolymers

“…Despite these outcomes, the aforementioned synthetic ease and oxidative stability make the BDT moiety a promising building block for designing new materials. 37 In the future, we will investigate the BDF moiety with stronger electron-accepting comonomers. Doing this would both reduce the polymer bandgap and allow for the use of additional alkyl character to improve solubility and improve film formation.…”

p-Type Conjugated Polymers Containing Electron-Deficient Pentacyclic Azepinedione

“…In OPV applications, the use of benzo­[1,2- b :4,5- b ′]­dithiophene (BDT) as the electron-rich comonomer has become prevalent due to its combination of high solubilizing power and optimal energy levels, and the overall polymer performance has been tuned by the choice of acceptor comonomer . In the past few years, several representative electron-deficient units, such as benzo­[1,2- c :4,5- c ′]­dithiophene-4,8-dione (BDD) and dithieno­[3′,2′:3,4;2″,3″:5,6]­benzo­[1,2- c ]­[1,2,5]­thiadiazole (DTBT) have been developed to endow high-performance BDT copolymer donors PM6 and D18. , To further enhance the performance of BDT-based polymers in single-junction and double-junction OPV cells, for both indoor and AM 1.5G applications, the development of new electron-deficient comonomers is important. ,− …”

“… 9 , 10 To further enhance the performance of BDT-based polymers in single-junction and double-junction OPV cells, for both indoor and AM 1.5G applications, the development of new electron-deficient comonomers is important. 7 , 11 − 15 …”

Designing of benzofuran‐based monomers for photodetectors through similarity analysis and library enumeration

“…Benzo[1,2-b:4,5-b 0 ]dithiophene (BDT) has been extensively used to design polymers for photovoltaics applications; however, benzo[1,2-b:4,5-b 0 ]difuran (BDF) has rarely been utilized in photovoltaic applications. 35 There could be various possibilities to modify benzodifuran building blocks for designing its derivatives. Using Harvard photovoltaic database, numerous unique building blocks are screened using benzodifuran building blocks as standard.…”