EMPIR-14IND12: Metrology for innovative nanoparticles (Innanopart)

• Forschungsstelle: METAS
• Projektnummer: F-5235.30063
• Projekttitel Englisch: EMPIR-14IND12: Metrology for innovative nanoparticles (Innanopart)

Schlüsselwörter (Englisch)

Nanoparticles, nanomaterials, traceable measurements, particle concentration, monodisperse particles

Kurzbeschreibung (Englisch)

Nanoparticles are increasingly used in innovative products manufactured by advanced industries and provide enhanced, unique properties of great commercial and societal value. The demand for high performance materials places increasingly stringent tolerances on the properties of nanoparticles. The Innanopart project focusses on the major unmet metrological needs in the production of high quality nanomaterials: measuring the concentration of particles and measuring the surface chemistry. These two measurements are critical to the performance of these novel materials in products and the development of valid measurement approaches, supported by documentary standards, will underpin trade and the supply chain for these novel products.

This is a joint research project carried out in the framework of the European Metrology Programme for Innovation and Research (EMPIR) (see:http://www.euramet.org/research-innovation/empir/). The EMPIR initiative is co-funded by the European Unions's Horizon 2020 research and innovation programme and the participating states. METAS is one of the project partners in the project.

Projektziele (Englisch)

The specific technical objectives of the project are to:

1. Develop traceable measurement and calibration protocols to measure particle number concentrations in liquid suspension with a target relative uncertainty of better than 10 % for spherical particles in the size range 1 nm to 1000 nm.
2. Develop methods to quantify the number concentration of particles in partially agglomerated or aggregated states within a liquid suspension of otherwise monodisperse primary particles and the ability to measure number concentration of particles with a non-spherical shape.
3. Develop standard procedures to traceably measure the chemical composition and thickness of the nanoparticle shell, both to within 10 % uncertainty.
4. Conduct two inter-laboratory studies to establish a good practice guide for industry and thereby establish laboratory-scale methods to enable valid, routine monitoring and quality control of particle concentration and surface chemistry for nanoparticle-based formulations and products.
5. Engage with industry that manufactures and or / exploits nanoparticles in order to facilitate the uptake of the technology and measurement infrastructure developed by the project, to support the development of new, innovative products, thereby enhancing the competitiveness of EU industry.

Abstract (Englisch)

All project goals were achieved. The Laboratory of Particles and Aerosols employed a setup consisting of an Electrospray generator (ES), a Differential Mobility Analyzer (DMA) and a Condensation Particle Counter (CPC) in order to measure the number concentration of nanoparticles in colloidal suspensions. The ES was coupled to a custom-made sample injection system based on a Microfluidic Pressure Controller and a liquid flow meter, which allowed the measurement of the suspension flow rate through the ES capillary.

In the context of the EMPIR-Innanopart project, the measurement efficiency of the setup could be determined based on the use of well-characterized reference suspensions (gold, silica and polystyrene NPs in the size range 10 nm – 200 nm). It was found that the measurement efficiency of the system depends strongly on the suspension flow rate through the ES generator and the properties of the suspension matrix and varies between 5% and 90%

Umsetzung und Anwendungen (Englisch)

The measurement efficiency of the ES-DMA-CPC method was investigated for the first time with a large variety of reference suspensions (of different NP materials and sizes). The results have shown that the method has a great potential for the measurement of NP concentration in colloids, however, more efforts are required in order to find useful applications in the field of metrology. More specifically, the design of the ES generator must be optimized in order to minimize particles losses upon aerosolization of the suspension, improving thus the transport efficiency of the particles through the system. To this aim, input/support from instrument manufacturers would be highly desirable.

Publikationen / Ergebnisse (Englisch)

in preparation