Miscibility Regulation and Thermal Annealing Induced Hierarchical Morphology Enables High‐Efficiency All‐Small‐Molecule Organic Solar Cells Over 17%

Abstract

Achieving an ideal morphology to realize efficient charge generation and transport is an imperative avenue to improve the photovoltaic performance of all small‐molecule organic solar cells (SM‐OSCs). Here, ternary SM‐OSCs are fabricated based on a new small molecule donor, SM‐mB, and an alloyed blend acceptor of Y6 and its derivative, L8‐BO, and desirable hierarchical morphology with appropriate nanoscale phase separation is successfully realized through adjusting the thermal annealing treatment conditions and compositions of mixed acceptors in the active layer. Then the ternary SM‐OSCs achieve an excellent PCE of 17.06 %, which is one of the best results for the SM‐OSCs so far. The desirable morphology can be ascribed to the optimization of the miscibility‐driven donor and acceptor blend morphology that takes full advantage of the individual advantages of both acceptors, which facilitate efficient charge generation and extraction with more balanced charge carrier mobilities. More importantly, the photovoltaic performance of the ternary SM‐OSCs possesses a high tolerance to the device fabrication conditions, including thermal annealing treatment, and is insensitive to film thickness, which is beneficial for large‐area manufacture and future practical applications.

Enhancing Efficiency and Stability in Organic Photovoltaics through Miscibility of High‐Tg Insulating Material with Y‐Series Nonfullerene Acceptors

“…We also explored the effect of SA9000 in L8-BO-based devices, noting that L8-BO demonstrates superior solubility in common organic solvents, attributed to its branched alkyl side chains. [32,33] The device performance was evaluated under the same conditions as Y6-based devices. As shown in Figure S4 and Table S3, Supporting Information, we observed that incorporating 2 wt% of SA9000 into PM6:L8-BO resulted in a modest increase in the average PCE, improving from 17.9% to 18.6% without the additive.…”

A highly crystalline donor enables over 17% efficiency for small-molecule organic solar cells

“…20–24 In addition, with the continuous updating of small molecule donors and acceptors, the film thickness insensitive, thermal annealing treated and non-halogen solvent processed high-performance SM-OSCs have been fabricated successively. 25,26 Recently, an efficient large-area SM-OSC with an area of 1 cm 2 was fabricated using a slot-die printing technology. 27 These results demonstrate that SM-OSCs could be a promising candidate for industrial application.…”

“…42 Until now, phenyl groups as conjugated side chains have been widely used to develop SM donors for high-efficiency SM-OSCs. 26 Recently, Chen et al designed and synthesized a donor material, HD-1, with a couple of thiazole side chains, which showed a favorable BHJ morphology with BTP-eC9. Therefore, the HD-1:BTP-eC9-based OSC gave a PCE of up to 17.19%.…”

Synergistic engineering of the Stokes shift for highly efficient and stable quasi-2D perovskite luminescent solar concentrators

“…To meet the growing demand for renewable energy, solar energy as the main renewable energy technology has been widely investigated. 1–3 Existing research on solar energy conversion mainly focuses on photovoltaics (PVs). 4 Besides conventional PV devices, luminescent solar concentrators (LSCs) have recently attracted great attention.…”