Environment-friendly 0D/2D nanocomposites for broadband UV-vis-NIR-sensitive photodetectors

• Applicant: Professor Dr. Dietrich R. T. Zahn
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 424154386

The development of new broadband-sensitive and self-powered photodetectors based on heterostructures of 0D nanocrystalline (quantum dots - QDs) and 2D few-layer and single-layer materials can be strongly boosted by the introduction of new toxic-metal free multinary chalcogenide QDs and readily available, stable semiconducting and conducting 2D nanosheets. The present project focuses on new reliable protocols of aqueous synthesis of multinary Cu(Ag)-In-Se and Cu-Zn-Sn-Se QDs with controlled composition/size, the relationships between the morphology and photophysical properties of such QDs, and the dynamics of photoinduced charge transfer in 0D/2D composites of metal-selenide QDs with single-layer reduced graphene oxide (RGO) and carbon nitride (SLCN) sheets as components of self-powered photodetectors. The project combines several inter-related research tasks, including (i) preparation of water-soluble composition- and size-selected Cu(Ag)-In-Se and Cu-Zn-Sn-Se QDs; (ii) detailed investigation of the electro- and photophysical properties of such QDs as well as their composites with SLCN and RGO; (iii) gaining deep insights into the mechanisms/dynamics of the photoinduced electron transfer between QDs and 2D moieties depending on the QD size/composition and acceptor properties of RGO and SLCN; (iv) selection of the most promising 0D/2D heterostructures as UV-vis-NIR-sensitive elements of self-powered photodetectors.This project has a distinct proof-of-concept character and will provide a fundamental basis for the design of new self-powered photodetectors with high figures of merit. It is also expected to have a marked impact on the development of new „green“ syntheses of vis-NIR-luminescing QDs, chalcogenide 0D materials with promising magnetic and thermoelectric properties, as well as broadband-sensitive photocatalysts of artificial photosynthetic processes.

• DFG Programme: Research Grants