Characterization of Nanoparticles with Wide-Angle Light Scattering

Principle of Wide-Angle Light Scattering
Principle of Wide-Angle Light Scattering
Inverse analysis of scattering data
Inverse analysis of scattering data and uncertainties

In this research topic we employ Elastic Light Scattering (ELS) for the characterization of Nanoparticle aggregates. In conventional methods the angular dependent scattered light is either detected using multiple detectors at fixed scattering angles or by one detector being rotated on a goniometer. In the first case of a few fixed detectors only a limited number of angles can be measured, using a single detector on a goniometer only allows for the measurement of stationary processes due to the long measurement procedure.

The newly developed measurement principle Wide-Angle Light Scattering (WALS) employs an ellipsoidal mirror simultaneously imaging the scattered light from a wide angular range onto a camera chip with a high angular resolution. This allows for a determination of aggregate size and morphology from a single camera frame. With WALS not only turbulent combustion processes can be investigated, but also an online surveillance of industrial particle production processes, like production of carbon blacks or silica particles, is possible. Furthermore, the high angular resolution allows for an inverse analysis of the scattering data to obtain parameters of the particle size distribution.

By a combination with other measurement techniques, such as Laser-Induced Incandescence, a comprehensive characterization of gas borne nanoparticles can be achieved.