High-Throughput Materials Discovery by Inkjet-Printing of Composition Spread Libraries

Abstract

High-throughput synthesis and screening rely on structurally diverse catalyst libraries. As a consequence of increased parallelization and integration of reactor and analysis systems, the requirements for new synthesis methodologies include even smaller amounts of samples, e.g. different multi-component mixed oxides in the mg or even μg-range have to be prepared reproducibly and fully automated. We tried to bring solution chemistry, composition spread libraries and a very high sample density together within one approach and tested inkjet printing of materials libraries using sol-gel recipes as synthesis method. Inkjet printing allows the deposition of liquid volumes in the pL range thus enabling the deposition of very small catalyst amounts. For the application of this technique in sol-gel chemistry several restrictions have to be handled, such as viscosity limitations of the printing head. Parameters as solvent, solvent amount, metal precursors, metal salt concentrations, deposition sequences etc. as well as gelification procedures have to be optimized. Catalytic screening relies on porous samples with high surface area to get conversions, which can be detected by HT screening methods. Thus, additionally the recipe itself as well as the support structure has to be optimized. In our first tests we used emission corrected IR thermography for screening.