Cellulose‐Based Microparticles for Magnetically Controlled Optical Modulation and Sensing
Abstract
Responsive materials with birefringent optical properties have been exploited for the manipulation of light in several modern electronic devices. While electrical fields are often utilized to achieve optical modulation, magnetic stimuli may offer an enticing complementary approach for controlling and manipulating light remotely. Here, the synthesis and characterization of magnetically responsive birefringent microparticles with unusual magneto‐optical properties are reported. These functional microparticles are prepared via a microfluidic emulsification process, in which water‐based droplets are generated in a flow‐focusing device and stretched into anisotropic shapes before conversion into particles via photopolymerization. Birefringence properties are achieved by aligning cellulose nanocrystals within the microparticles during droplet stretching, whereas magnetic responsiveness results from the addition of superparamagnetic nanoparticles to the initial droplet template. When suspended in a fluid, the microparticles can be controllably manipulated via an external magnetic field to result in unique magneto‐optical coupling effects. Using a remotely actuated magnetic field coupled to a polarized optical microscope, these microparticles can be employed to convert magnetic into optical signals or to estimate the viscosity of the suspending fluid through magnetically driven microrheology. Mehr anzeigen
Publikationsstatus
publishedExterne Links
Zeitschrift / Serie
SmallBand
Seiten / Artikelnummer
Verlag
Wiley‐VCH VerlagThema
Cellulose nanocrystals; Magneto-optical properties; Microfluidics; Microparticles; Polarized lightOrganisationseinheit
03831 - Studart, André R. / Studart, André R.
09619 - Schürle-Finke, Simone / Schürle-Finke, Simone
Förderung
159906 - Hierarchisch strukturierte zellulose-basierte Komposite (SNF)