Kinetics Manipulation Enables High‐Performance Thick Ternary Organic Solar Cells via R2R‐Compatible Slot‐Die Coating

Abstract

Power conversion efficiency (PCE) of organic solar cells (OSCs) has crossed the 18% mark for OSCs, which are largely fabricated by spin‐coating, and the optimal photoactive thickness is limited to 100 nm. To increase reproducibility of results with industrial roll‐to‐roll (R2R) processing, slot‐die coating coupled with a ternary strategy for optimal performance of large‐area, thick OSCs is used. Based on miscibility differences, a highly crystalline molecule, BTR‐Cl, is incorporated, and the phase‐separation kinetics of the D18:Y6 film is regulated. BTR‐Cl provides an early liquid–liquid phase separation and early aggregation of Y6, which slightly improves the molecular crystallinity and vertical phase separation of the ternary blends, resulting in high PCEs of 17.2% and 15.5% for photoactive films with thicknesses of 110 and 300 nm, respectively. The ternary design strategy for large‐area and thick films is further used to fabricate high‐efficiency flexible devices, which promises reproducibility of the lab results from slot‐die coating to industrial R2R manufacturing.

Fluid Mechanics Inspired Sequential Blade‐Coating for High‐Performance Large‐Area Organic Solar Modules

“…[ 5,6 ] While the upscaling fabrication of OSCs is essential for industrialization, there is still a huge PCE lag between small‐area and large‐area OSCs. [ 7–11 ] Thus, in addition to the advances in inherent semiconductor properties, a crucial consideration for the development of large‐area OSCs and OSC modules lies in the manner in which they are processed and relevant film morphology evolution.…”

Simultaneously Decreasing the Bandgap and Voc Loss in Efficient Ternary Organic Solar Cells

“…Organic solar cells (OSCs) have stimulated extensive interest as an emerging photovoltaic technology because of their advantageous properties such as lightweight, flexibility, semitransparency, and large-area fabrication via solution processing methodologies. [1][2][3] The rapid progress in the development of fused-ring non-fullerene acceptors, e.g., Y6, widened the locates in both the donor and the acceptor material has seldom been indicated yet.…”

“…Organic solar cells (OSCs) have stimulated extensive interest as an emerging photovoltaic technology because of their advantageous properties such as lightweight, flexibility, semitransparency, and large‐area fabrication via solution processing methodologies. [ 1–3 ] The rapid progress in the development of fused‐ring non‐fullerene acceptors, e.g., Y6, widened the absorption profiles toward the near‐infrared region and led to a significant boost in photons harvesting as well as the power conversion efficiency (PCE) of OSCs. [ 4–8 ] Constructing OSC with narrow bandgap materials could widen the light absorption range and enhance short‐circuit current ( J sc ) of OSC, [ 9 ] but the open‐circuit voltage ( V oc ) of the device will also decrease due to the offset decreasing between the highest occupied molecular orbital (HOMO) energy levels of donor and lowest unoccupied molecular orbital (LUMO) energy levels of acceptor materials.…”

Synergetic Strategy for Highly Efficient and Super Flexible Thick‐film Organic Solar Cells

“…Moreover, the inferior mechanical stability also delays the development and application of flexible OSCs. [9][10][11] Accordingly, overcoming thickness sensitivity of active layer and improving mechanical stability of device are urgent problems to be solved in industrial preparation of high performance flexible OSCs.…”

“…However, it is difficult to realize in the preparation of such film by solution method in industrial production. [9,12] Slight variations of the thickness will seriously affect photon capture and charge recombination, and ultimately reduce the photovoltaic performance of device. It is of great significance to develop high efficiency thick-film OSCs.…”