COSYMONA

Combustion Synthesis of Functional Metal Oxide Particles

26/01/2009 to 31/12/2010

The goal of this project is to explore combustion synthesis of tin-oxide nanoparticles for gas sensor applications. Particles will be made by flame spray pyrolysis (FSP) and directly deposited onto substrates with electronic functionality.

Sensor performance will be systematically evaluated and related to standard and microgravity process conditions. A dedicated reactor will be built for FSP, a highly versatile process for manufacture of nanoparticles with superior catalytic, mechanical and electrochemical properties. Organometallic precursors for tin oxide and dopant metals will be evaluated and selected for synthesis of nanostructured sensors with the appropriate morphology and optimal characteristics. Sensor particles and film properties will be characterized systematically by a range of state-of-the-art techniques; additionally sensing performance will be thoroughly assessed. A unique focus of this effort would be the development of new, ultra-sensitive sensors with very thin functional layers that can be processed at the short residence times available under microgravity conditions on earth. Microgravity would be anticipated to influence stagnation layer thickness and deposition dynamics. Additional effects on flame temperature profile may influence particle agglomeration and sensor film morphology. A number of experiments are to be performed at the Drop-Tower Bremen, Germany. The limited number of drops requires dedicated in situ diagnostics and current and new approaches of 2-dimensional particle and temperature measurement will be developed for the special conditions of this process and of the drop tower. Thermophoretic sampling and direct deposition sensor fabrication will allow verification of in situ particle characterization and comparison with ground-based results.