Gas Phase Synthesis of Inorganic Nanomaterials on the Pilot Plant Scale

key applications for nanomaterials within rapidly developing markets. The production of nano scaled materials from gaseous precursors in the gas phase is a so called bottom-up method, the advantages of this synthesis route are process control, high purity products and the opportunity to design a continuous process. Generally, the highly specific properties of particulate systems are directly correlated with the size of each particle and applications often require highly defined properties.<br/>In this work we provide an overview of our combustion, thermal decomposition and plasma assisted material synthesis on the pilot plant scale. Furthermore, direct transfer of these materials into processable dispersions using wet electro precipitator technology will be presented.<br/>The combustion based flame spray synthesis is a widely used in lab scale for the synthesis of nanomaterials, but has not reached industrial scale yet. Here, we present the generation of particles using easily available metal nitrates and demonstrate their conversion into defined nanoparticles in a spray flame. The composition of the particles can be adjusted and range from single metal oxides like titania to complex lanthanum strontium manganite (LSM or LSMO) perovskite particles with defined metal ratios. The particles are typically used in catalysis applications like hydrogen generation in electrolysis or the decomposition of versatile oxide components. We will demonstrate oxygen evolution ratio measurements on these materials.<br/>Thermal decomposition is used for the generation of pure silicon material, which is a candidate for battery application. The decomposition of silane (SiH4) in a nitrogen/hydrogen atmosphere leads to the formation of highly crystalline material, which can be doped on demand. Production rates of up to 1kg/h material can be achieved using this method. Battery performance of silicon based materials has been evaluated and reveals promising results for future applications.<br/>The plasma based system decomposes precursors at higher temperatures (T &gt; 2000K) into atoms and subsequent nucleation leads to particle formation, while a steep temperature gradient helps to obtain nanomaterial with designed characteristics.<br/>We report on the formation of graphene, since it offers high potential to improve a wide range of energy applications. It is well known that the combination of high production rates and material with defined properties is a major challenge in graphene synthesis. To address this, we performed eco-friendly continuous gas- phase synthesis of graphene on a pilot plant scale using easily available ethanol as precursor material. For this purpose, ethanol is evaporated and subsequently fed through an argon-hydrogen plasma generated by microwave radiation. The graphene powder is ex-situ analyzed by scanning and transmission electron microscopy as well as RAMAN spectroscopy, which reveals the typical signal of graphene with low defects. Results reveal that a throughput of 200 g/h of ethanol and low plasma energy supports the formation of graphene structures and, therefore, paves the way for energy efficient synthesis.