At VSPARTICLE we believe that bridging the gap between research and industry is key in exploiting the full potential of nanotechnology. Researchers are becoming better in modifying materials on an atomic level. However, thin film fabrication industry is still lagging the right tools to manufacture at an industrial scale while maintaining atomic resolution. VSPARTICLE is currently developing an industrial particle source which is based on the same spark ablation technology as used in the VSP-G1. In this way, new results in research can easily be translated to industrial production.
Spark ablation is a gas phase physical process for the continuous production of very small particles, that can be switched on and off at the touch of a button. The inputs of the process are a conductive feedstock (e.g. Ag or Cu rod), electricity, and a carrier gas. The output is a highly concentrated aerosol of pure (metal) nanoparticles suspended in a clean gas at low temperature (<50 °C).
- Physics based process
- Start/stop at the push of a button
- No chemical waste
- Any (semi)conducting material
- High control on particle size
- Room temperature and pressure
With inert carrier gases such as Ar and N2, pure metal nanoparticles are produced with surfaces free from (organic) contaminants. By generating nanoparticles on demand, VSPARTICLE allows you to incorporate nanoparticles directly into your end product without worrying about handling, storage and stability (oxidation). The produced nanoparticles are directly incorporated into the next process step or applied in a product by, for example, impaction, electrostatic precipitation or diffusion. This way the unique physical properties of the nanoparticles are directly available in the product. The carrier gas can simply be recycled by passing it through a filter and used again, minimizing the environmental impact of the process. Because no waste streams are produced, spark ablation is uniquely suitable for integration into (existing) production processes.
Particle growth is determined by a physical process that allows the mean size of the nanoparticles to be controlled from several atoms to tens of nanometers, by modifying flow and energy input in an intuitive manner. Because of the high temperature in the spark (>20.000K), there is no practical limit to the materials that can be processed. In the most basic form, the material is an elemental metal.
General guidelines on spark operating conditions.
Tabrizi, N. S. et al., Journal of Nanoparticle Research (2009), doi: 10.1007/s11051-008-9407-y
Applying metal coatings on nanoparticle aerosols by spark ablation.
Pfeiffer, T. V. et al., Materials (2015), doi: 10.3390/ma8031027
Production of clusters comprising <25 silver atoms.
Maisser, A. et al., Aerosol Science and Technology (2015), doi: 10.1080/02786826.2015.1080812
Original description of aerosol particle generator for production of <10nm aerosols of carbon and gold.
Schwyn, S. et al., Journal of Aerosol Science (1988), doi: 10.1016/0021-8502(88)90215-7
Scale-up considerations and the relation of spark discharge to other plasma based aerosol methods.
Hontañón, E. et al., Journal of Nanoparticle Research (2013), doi: 10.1007/s11051-013-1957-y
Use of spark generated nanoparticles in studying coagulation of very small particles in a gas, indicating a 104 enhancement of dispersion forces in silver.
Burtscher, H., & Schmidt-Ott, A., Physical Review Letters (1982), doi: 10.1103/PhysRevLett.48.1734
Spark ablation is a versatile technology that works with a wide variety of materials, including metals (e.g. silver, copper, gold, platinum, tungsten or nickel), semiconductors (e.g. silicon) and carbon. The VSP-G1 ablates materials from two electrodes, which enables you to play with the elemental composition. In this way, even immersible materials can be mixed into nanoparticles.