Organic Solar Cells Based on a 2D Benzo[1,2‐b:4,5‐b′]difuran‐Conjugated Polymer with High‐Power Conversion Efficiency

Abstract

A novel 2D benzodifuran (BDF)-based copolymer (PBDF-T1) is synthesized. Polymer solar cells fabricated with PBDF-T1 show high power conversion efficiency of 9.43% and fill factor of 77.4%, which is higher than the performance of its benzothiophene (BDT) counterpart (PBDT-T1). These results provide important progress for BDF-based copolymers and demonstrate that BDF-based copolymers can be competitive with the well-studied BDT counterparts via molecular structure design and device optimization.

On the Efficiency Limit of Conjugated Polymer:Fullerene‐Based Bulk Heterojunction Solar Cells

“…[ 52,53 ] Fill factors in this range have been reported for BHJ solar cells recently. [ 54 ] Some optimization approaches discussed above may only be applicable to hero devices. That is ultrapure materials or advanced light managements structures may be too expensive to be used in commercial products.…”

A twisted monomeric perylenediimide electron acceptor for efficient organic solar cells

“…Among various materials used for acceptors, fullerene derivatives act as the protagonists of electron acceptors, which lead the power conversion efficiencies (PCEs) to 11% for single junction OSCs [8][9][10][11][12]. Despite the achievements of fullerene derivatives in laboratory scale devices, the high-cost production, inflexibility in chemical modification, and weak light absorption in the visible region of fullerenes hamper their practical applications [13][14][15][16].…”

Medium Bandgap Polymer Donor Based on Bi(trialkylsilylthienyl‐benzo[1,2‐b:4,5‐b′]‐difuran) for High Performance Nonfullerene Polymer Solar Cells

“…[7] We also synthesized a similar 2D-conjugated D-A copolymer J71 with trialkylsilyl substituent on the thiophene conjugated side chains of BDTT unit, the PCE of the NF-PSCs based on J71:ITIC reached 11.4%. [29] However, there is no report on the application of the BDF-based copolymers as donor in NF-PSCs. [23][24][25][26][27][28] For example, compared with BDT-based polymers, the highest occupied molecular orbital (HOMO) energy levels of the corresponding BDF-based polymers were always downshifted, which is beneficial to higher open circuit voltage (V oc ) of the PSCs with the polymer as donor.…”