Over 18% Efficiency Ternary Organic Solar Cells with 300 nm Thick Active Layer Enabled by an Oligomeric Acceptor

Abstract

The development of high‐efficiency thickness‐insensitive organic solar cells (OSCs) is crucially important for the mass production of solar panels. However, increasing the active layer thickness usually induces a substantial loss in effcicency. We herein adopt a ternary strategy to break this dilemma, in which an oligomer DY‐TF was incorporated into PM6:L8‐BO system as a guest component. The S···F intramolecular noncovalent interactions in the backbone endows DY‐TF with a high planarity. Upon the addition of DY‐TF, the crystallinity of the blend is effectively improved, leading to increased charge carrier mobility, which is highly desirable in the fabrication of thick‐film devices. As a result, a thin‐film PM6:L8‐BO:DY‐TF based device (110 nm) shows a power conversion efficiency (PCE) of 19.13%. Impressively, when the active layer thickness increases to 300 nm, an efficiency of 18.23% (certified as 17.8%) is achieved, representing the highest efficiency reported for 300‐nm‐thick OSCs thus far. Additionally, a blade‐coated thick device (300 nm) delivers a promising PCE of 17.38%. This work brings new insights into the construction of efficient OSCs with high thickness tolerance, showing great potential for roll‐to‐roll printing of large‐area solar cells.This article is protected by copyright. All rights reserved

Dithienoquinoxaline-quaterthiophene wide bandgap donor polymers with strong interchain aggregation for efficient organic solar cells processed with a non-halogenated solvent

“…It should be noted that in the short wavelength range from 300 to 450 nm, increasing the thickness of the active layer can contribute to higher spectral response. This behavior has been observed before, 64–67 which is coming from thick blend film enhanced absorptions in this band. Our results suggest that the oligothiophene based polymer donor PQx4T-2F is a good candidate for roll-to-roll printing with a non-chlorinated solvent.…”

Regulating Crystallinity Mismatch Between Donor and Acceptor to Improve Exciton/Charge Transport in Efficient Organic Solar Cells

“…To confirm whether the guest molecule features better compatibility with PM6 donor than Y6 acceptor, as inferred by the results of UV/Vis absorption, the miscibility was calculated using DSC to calculate the Flory-Huggins interaction parameter (χ) of different blends. [26] The χ value of the organic material in the molten state was determined by measuring the depression in the melting point temperature of the blends. The DSC heating curves of BDTPF4-C6 : PM6 and BDTPF4-C6 : Y6 blends are shown in Figure 2a and 2b.…”

“…Compared to the first two approaches, a ternary strategy that involves adding a third component as a guest molecule, emerged as a promising choice. [22][23][24] This third component can be selected to enhance the compatibility of Y6-type acceptors, thereby reducing their crystallinity and aggregation effects, [25,26] or to improve the crystallinity of the polymer donors by introducing guest molecules with good compatibility. [27,28] Although substantial research has focused on regulating the Y6-type acceptors, comparatively limited attention has been paid to the effective control of polymer donors.…”

Regulating Crystallinity Mismatch Between Donor and Acceptor to Improve Exciton/Charge Transport in Efficient Organic Solar Cells

“…Compared to the first two approaches, a ternary strategy that involves adding a third component as a guest molecule, emerged as a promising choice. [22][23][24] This third component can be selected to enhance the compatibility of Y6-type acceptors, thereby reducing their crystallinity and aggregation effects, [25,26] or to improve the crystallinity of the polymer donors by introducing guest molecules with good compatibility. [27,28] Although substantial research has focused on regulating the Y6-type acceptors, comparatively limited attention has been paid to the effective control of polymer donors.…”