Screening Quinoxaline-Type Donor Polymers for Roll-to-Roll Processing Compatible Organic Photovoltaics

Abstract

We demonstrate, by screening a library of four derivatives of benzodithiophene–quinoxaline (BDT-QX)-based polymer, that BDT-QX are donor polymer candidates for large-scale coating of organic photovoltaic (OPV) active layers. Our study shows that pairing them with a twisted N-annulated perylene diimide (PDI) dimer, which solid-state aggregation can be induced via diphenyl ether (DPE) solvent additive, yields OPV devices with power conversion efficiency (PCE) over 5%. The active layers, both spin-coated (from o-xylenes and o-methylanisole) and slot-die-coated (from o-xylenes), maintain a high open-circuit voltage (V oc) over 1 V and a fill factor (FF) of ca. 60%, with a maximum PCE of respectively 6.07 and 4.11%, which show promise for compatibility with roll-to-roll, non-halogenated processing of OPV devices.

Exploring the Effect of the Irradiation Time on Photosensitized Dendrimer-Based Nanoaggregates for Potential Applications in Light-Driven Water Photoreduction

“…This potential is demonstrated by the effect of the radiant energy emitted by the sun on natural photosynthesis processes, demonstrating the feasibility of efficiently using sunlight to produce the photoinduced cleavage of the chemical bonds of water molecules [13,14,15]. Considering this, gaining a better understanding of natural photosynthesis at the molecular level has attracted much attention lately in order to create artificial photosynthetic systems having photoactive and donor–acceptor compounds [16,17,18,19]. Indeed, a significant amount of research effort has been directed toward the development of artificial systems composed of covalently attached molecules [20,21] or supramolecular arrangements [22,23].…”

Tackling Performance Challenges in Organic Photovoltaics: An Overview about Compatibilizers

“…Unsubstituted DPE is investigated by Zheng et al in the frame of PTB7:PC 71 BM OPVs preparation [165]; an addition of 4% v/v DPE caused a three-fold PCE enhancement (from 2% to 6%), due to an increased absorption in the visible range revealed by optical microscopy (increased absorption peak at 450 nm) formation of ordered packing of the PTB7, and reduction of PC 71 BM to the 500 nm range (as proofed by AFM). In a different study, Laventure and colleagues use DPEs for tuning the solid-state aggregation of a twisted N-annulated perylene diimide acceptor dimer [166]. AFM images support the hypothesis by revealing that photoactive layers prepared with no DPE present the molecular acceptor aggregated with fibrillar morphology, while the films processed with DPE show an evolution in the topography, from fibrillar to granular.…”

Red Organic Light-Emitting-Diodes based on a N-Annulated Perylene Diimide Dimer

“…The N-annulated PDI dimer, tPDI2N-EH ( Figure 1a) 29 , can be synthesized on multi-gram scale, is semiconducting, and can be coated via roll-to-roll processes from non-halogenated solvents 18,19 .…”

“…The perylene diimide (PDI) chromophore is one of the best candidates to construct new emitters for solution-processed red OLEDs owing to a pure red colour, high quantum yield photoluminescence, and high thermal and photochemical stability [15][16][17] . Furthermore, PDIs can be rendered soluble in a range of solvents and thus are suitable for large area roll-to-roll coating [18][19][20] .…”