Terthiophene based low-cost fully non-fused electron acceptors for high-efficiency as-cast organic solar cells

Abstract

Fully non-fused electron acceptors (FNEAs) have shown a promising prospect for commercial applications of organic solar cells (OSCs) due to their simple structures and low costs. Herein, two terthiophene-based NFEAs...

A rare case of iodinated non-fullerene acceptors for high-performance organic solar cells without post-treatments

“…The great structural complexity of organic molecules and intrinsically metastable micromorphology of blended films 16,18–20 make the construction of OSCs with both high performance and free of post-treatments very challenging. Despite the lack of structure–activity relationships, 21–23 a relatively clear clue has been revealed that not only efficient π–π stackings but also sufficient noncovalent interactions, like halogen bonding etc. , should be considered, if much enhanced intermolecular interactions and thermodynamically stable morphologies are expected.…”

“…The most distinctive advantage of our recently explored CH-series NFAs lies in the sufficient structural modification sites on the molecular skeleton of central units, which has afforded a blowout PCE growth of resulting OSCs. 20,24,27 Particularly, a huge possibility for molecular packing optimization through quite a minor structural modification (like halogenation) on central units of CH-series NFAs has been manifested, 21 demonstrating the powerful capacity in reducing E b , increasing relative dielectric constant, facilitating charge generation/transport, etc. 37 This unique property of CH-series NFAs is really exciting, because the hitherto inaccessible iodization of other NFAs such as ITIC, 38 F 39 and Y-series molecules 40 could be easily achieved if introducing iodine on central units rather than end groups.…”

Ternary organic solar cells with a selenophene-containing donor guest achieve a high efficiency of 18.41%

“…D18 was developed by Ding's group in 2020, which displays excellent photoelectric properties, showing high universality when combined with various kinds of NFAs. [50][51][52] To maximize the light harvesting and get the matched energy levels, herein, D18 and 2,2 0 -((7,8-difluoro-15,16-bis(2-hexyldecyl)-3,12-diundecyl-15,16-dihydrothieno[2 00 ,3 00 :4 0 ,5 0 ]thieno[2 0 ,3 0 :4,5]pyrrolo [3,2-a]thieno[2 00 ,3 00 :4 0 ,5 0 ]thieno[2 0 ,3 0 :4,5]pyrrolo[2,3-c]phenazine-2,13-diyl)bis(methaneylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene)dimalononitrile (CH-6F) were selected as the host donor and acceptor materials, respectively, to fabricate the SM donor doped ternary OSCs. The incorporation of CBTSeHR enhances light-capturing capability in the range of 550-700 nm.…”

Completely non-fused ring acceptors with low non-radiative energy loss enabled by end-group modulation

“…[19][20][21][22] To address the critical cost issues, many research studies have been conducted to design novel non-fused ring electron acceptors (NFREAs), intending to realize low-cost and highly efficient acceptors simultaneously. 23,24 In order to obtain comparable PCEs with their fused-ring counterparts, NFREAs should have suitable optical band-gaps (E g s), favorable aggregation behaviors and planar stable chemical conformations, which can be tuned using chemical modification methods. For example, Chen et al reported a NFREA named PTB4Cl by replacing F with Cl on the terminal groups of PTB4F.…”

“…19–22 To address the critical cost issues, many research studies have been conducted to design novel non-fused ring electron acceptors (NFREAs), intending to realize low-cost and highly efficient acceptors simultaneously. 23,24…”