Development of the state diagrams of PBTTT and a novel PBTTT de-rivative in combination with PC61BM for organic near-infrared cavi-ty photodetectors

Activiteit: Talk or presentation at a conference

Description

In organic cavity-based near-infrared (NIR) photodetectors, the formation of an intermolecular charge transfer (CT) state at the interface between the donor and the acceptor plays a crucial role in the device performance. For this particular ap-plication, a high interfacial contact area is required, as it results in relatively strong CT absorption [1]. A benchmark system, PBTTT:PC61BM, is selected because the intercalation of the fullerene acceptor between the side chains of the polymer donor maximizes the PBTTT:PC61BM contact [2]. A novel PBTTT derivative with al-ternating alkyl and alkoxy substituents was developed to further lower the energy gap between the HOMO of the donor and the LUMO of PC61BM, and therefore extend the CT absorption of the device more into the NIR.
In this research, the benchmark donor material PBTTT and the novel alkoxy-alkyl-PBTTT polymer, as well as their blends with PC61BM, are studied by Rapid Heat-Cool DSC (RHC). RHC allows a relatively wide range of heating and cooling rates up to 2000 K/min, thanks to its unique infrared furnace design and small sample size (ca. 250 ╬╝g). Using this technique, the state diagram of alkoxy-alkyl-PBTTT:PC61BM is constructed for the first time. The comparison with the bench-mark system regarding the state diagrams and their complex thermal behaviour, including cocrystal formation and eutectic transitions, is discussed with the help of synchrotron XRD results.
Periode31 aug 2021
EvenementstitelICTAC 2020
17th International Congress on Thermal Analysis and Calorimetry: 8th Joint Czech-Hungarian-Polish-Slovakian Thermoanalytical Conference (V4 8) and 14th Conference on Calorimetry and Thermal Analysis of the Polish Society of Calorimetry and Thermal Analysis (CCTA 14)
EvenementstypeConference
Mate van erkenningInternational