Project Details
Projekt
Energy-efficient syntheses of intermetallic compounds using a microwave-assisted polyol process. Elucidation of the reaction process towards the development of adapted reaction conditions for the production of tailor-made nanostructured materials.
Subject Area
Solid State and Surface Chemistry, Material Synthesis
Term
from 2018 to 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 413437826
The polyol process is a resource-efficient method for the production of metallic micro- and nanoparticles. In this process, metal salts are dissolved in a polyalcohol and the metal cations are subsequently reduced at temperatures below T = 300 ° C. The polyol serves as solvent and reducing agent as well as surfactant which can influence the particle shape and size. Sintering and aggregation of the particles can often be prevented. In addition to elemental metals such as, e.g. silver, gold or platinum, nanoparticles of binary and multinary intermetallic compounds are also obtained. The reaction temperatures which are comparatively low compared to traditional melting or sintering processes can also lead to kinetically controlled crystallizations and to metastable phases which are difficult or not accessible by classical syntheses routes. Polyol reactions often proceed efficiently and to uniform products with defined particle size and morphology when rapid heating of the reactant mixture by microwave radiation is applied.Despite the more than 30 year history of the polyol process with numerous experimental investigations and theoretical considerations, little is known about the redox mechanisms.In this project, the elucidation of the reaction mechanisms of polyol reductions by means of ex and in situ techniques is therefore focused on. The knowledge of reaction mechanisms is of fundamental importance for the development of synthetic pathways for new, ternary intermetallic phases, which are investigated in a second work package.
DFG Programme
Research Grants
