Solid Additive Delicately Controls Morphology Formation and Enables High‐Performance in Organic Solar Cells

Abstract

Volatile solid additives are an effective strategy for optimizing morphology and improving the power conversion efficiencies (PCEs) of organic solar cells (OSCs). Much research has been conducted to understand the role of solid additives in active layer morphology. However, it is crucial to delve deeper and understand how solid additives affect the entire morphology evolution process, from the solution state to the film state and the thermal annealing stage, which remains unclear. Herein, the use of a highly crystalline solid additive, phenoxathiin (Ph), in D18‐Cl:N3‐based OSCs and study its impact on morphology formation and photovoltaic performance is presented. Owing to its good miscibility with the acceptor N3, Ph additive can not only extend the time for the active layer to form from the solution state to the film state, but also provide sufficient time for acceptor aggregation. After thermal annealing, Ph solid additive volatilizes better aligned the N3 molecules and formed a favorable hybrid morphology. Consequently, the D18‐Cl:N3–based OSC exhibited an outstanding PCE of 18.47%, with an enhanced short‐circuit current of 27.50 mA cm−2 and a fill factor of 77.82%. This research is spurring the development of high‐performance OSCs using solid additives that allow fine control during morphology development.

A–A Strategy Enables Desirable Performance of All-Polymer Solar Cells Fabricated with Nonhalogenated Solvents

“…The intermolecular pre-aggregation of the two polymers in solution would be advantageous in forming photoactive blend films with high domain purity and appropriate morphology. 47 The highest occupied molecular orbital (HOMO) energy levels and lowest unoccupied molecular orbital (LUMO) energy levels of PM6, PY-FBTA, and PY-DPP were estimated by cyclic voltammetry (Figures 3b and S11). The reference electrode, internal standard, and work electrode were Ag/ AgCl, Fc/Fc + couple (0.43 eV), and ITO, respectively.…”

A high-performance dual-functional organic upconversion device with detectivity approaching 1013 Jones and photon-to-photon efficiency over 20%

“…36 Therefore, an appropriate morphology is of vital significance for realizing efficient conversion of photogenerated excitons into free carriers, as well as for carrier transport, finally resulting in a high-performance device. 37–39…”

High‐Performance Binary All‐Polymer Solar Cells with Efficiency Over 18.3% Enabled by Tuning Phase Transition Kinetics

“…[10][11][12][13] Unfortunately, the performance of All-PSCs has lagged behind that of OSCs based on non-fullerene small molecular acceptors, primarily due to non-optimal BHJ morphology. [14][15][16][17][18] Therefore, more efforts should be made to deeply understand and regulate the morphology formation to advance the development of All-PSCs.…”