Plasma-based synthesis of nanomaterials

Nanomaterials, owing to their nanoscopic dimensions, offer unique physico-chemical properties, which make them promising for applications in fields such as plasmonics, sensing and catalysis. At INP, complementary plasma-based approaches are pursued to create a large range of nanomaterials.

Nanoparticles from nanoparticle beam deposition can be obtained from a supersaturated metal vapor via a magnetron-based gas aggregation source, resulting in a high-purity, surfactant-free deposition with good process control on all vacuum-compatible substrates, ranging from solid substrates, over fabrics and fibers, flexible and soft substrates towards liquids. Gas phase synthesis enables fabrication of complex nanoparticles with tailored composition (controlled alloying) and morphology (core-shell, core-satellite, multicore-shell). To gain a deeper understanding of the processes involved in nanoparticle formation within the gas aggregation source, we have introduced a variety of in-situ diagnostic techniques that allow for enhanced monitoring and control of the deposition process.

In-liquid plasma processing (ILP) is a new eco-friendly and single-step process for the production of nanomaterials at high cost-efficiency. ILP synthesis exhibit attractive advantages, such as a simple reactor design and rapid processing times, no need of toxic chemicals and can easily be upscaled and operated as a continuous process. Production of nanoparticles by ILP can be carried out from solid and liquid precursors and enable production routes via exfoliation, pyrolysis, fragmentation or crystallization of nanomaterials. Also, hydration, intercalation, functionalization, and phase transitions may occur in ILP synthesis, giving rise to a large range of new structures formed. Charged and neutral species with different energies, lifetimes, and densities may be produced by specific adaption of the electrode setup, precursor solution or suspension, applied voltage, frequency, pulse width, and process time.