Exploring energy and environmental challenges with functionalized silicon nanoparticles

In order to reduce global greenhouse gas emissions, and to meet the EU's commitment of a reduction of 80% by 2050, it is necessary to make major advances in efficient, clean and secure energy conversion and use. Therefore, thermoelectric materials have become an area of great interest.1 Phenylacetylene functionalized Silicon quantum dots (SiQDs) are showing potential to provide highly efficient thermoelectric materials. We have successfully synthesized Phenylacetylene capped SiQDs via the micelle reduction method.2 These conjugated ligands would allow transport of electrons through the π orbitals. A preliminary characterization of this system shows an electric conductivity in the region of 24 S·m-1, thermal conductivity 0.10 Wm-1K-1 and a Seebeck coefficient of 3228 µVK-1 at 300 K, with an estimated ZT in the region of 0.6.2Knowledge of the microscopic conduction rates and mechanisms of these materials would be of much use in our attempts to improve these materials by design. Muon spectroscopy appears to be an elegant method of measuring these microscopic properties for conducting organic polymers, materials which are structurally similar to the ligands found in our SiQDs. Further, muonium adducts to CC triple bonds in other organic compounds have already been characterised by our group.3 This talk is to present recent results obtained from Muon study in PSI, Switzerland.In this presentation, I will also briefly talk about recent research in batteries and solar conversion.