Holographic characterization of individual colloidal spheres’ porosities
نویسندگان
چکیده
Synthetic colloidal spheres play a central role in applications as diverse as catalysis, medical diagnostics, and photonics. Even as many applications advance toward single-sphere implementations, methods for characterizing colloidal spheres typically offer only sampleaveraged overviews of such properties as spheres’ sizes and porosities. Moreover, such characterization methods as mercury adsorption porosimetry, nitrogen isotherm porosimetry, transmission electron microscopy and x-ray tomography require preparatory steps that may affect particles’ properties. Here, we demonstrate that holographic video microscopy can meet this need for particleresolved in situ characterization, and that results of these optical measurements can be interpreted to measure individual spheres’ porosities.
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