Reexamining the Role of Solution-Cast Ferroelectric Polymer Interlayer toward Enhanced Efficiency and Stability in Conventional Organic Solar Cells

Abstract

Interfacial modification is crucial for achieving efficient and stable organic solar cells (OSCs). Herein, an N,N-dimethylformamide (DMF) solution-cast poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) interlayer was applied to enhance the efficiency and stability of a range of OSCs, and the underlying mechanism was revealed via morphological and device physics studies. DMF rinse during the P(VDF-TrFE) interlayer casting process strengthens π–π stacking of the active layer with fibril aggregation, optimized phase separation, and vertical component distribution, while the P(VDF-TrFE) interlayer with rich diploes contributes to increased surface potential and internal electric field. The synergistic effect of the P(VDF-TrFE) interlayer and DMF rinse increases the PCEs of PM6:IT-4F, PM6:C5–16, and PM6:L8-BO OSCs from 12.7, 17.9, and 18.2% to 13.1, 18.7, and 18.8%, respectively. Additionally, OSCs containing the P(VDF-TrFE) interlayer also showed improved storage stability.

Brominated Quaternary Ammonium Salt-Assisted Hybrid Electron Transport Layer for High-Performance Conventional Organic Solar Cells

“…Device fabrication procedures including substrate cleaning as well as deposition of PEDOT:PSS, 2PACz, PM6:C5-16, PM6/L8-BO, PDINN, and Ag can be found in our previous work. , The optimal thickness for PM6:C5-16 and PM6/L8-BO are ca. 80 and 95 nm, respectively.…”

Solution-Processed Co3O4-Based Hole Transport Layer for Nonfullerene Organic Solar Cells

“…32 Generally, nonfullerenebased OSCs' conventional device structure indicated more efficiency than the inverted configuration. 9,33 Significantly, the most dominated HTL is poly (3,4- processability. 34−36 However, the hygroscopic and acidic nature of PEDOT:PSS severely reduces the quality of OSCs as it corrodes the indium tin oxide (ITO) surface.…”

“…In general, the function of the HTL is to facilitate hole transport generated by light absorption in the active layer toward the anode, competing with the geminate and nongeminate recombination . Generally, nonfullerene-based OSCs’ conventional device structure indicated more efficiency than the inverted configuration. , Significantly, the most dominated HTL is poly­(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) for well-performing conventional OSCs due to having a suitable work function, good transmittance, high hole mobility, and simple solution processability. − However, the hygroscopic and acidic nature of PEDOT:PSS severely reduces the quality of OSCs as it corrodes the indium tin oxide (ITO) surface. , The other HTLs, such as transition metal oxides (V 2 O 5 , MoO 3 , NiO X , WO 3 , etc. ), have gained a lot of attention due to their excellent transmittance, high work function, and better stability in the open air .…”