Cellulose Based Photonic Materials Displaying Direction Modulated Photoluminescence

Abstract

Photonic materials featuring simultaneous iridescence and light emission are an attractive alternative for designing novel optical devices. The luminescence study of a new optical material that integrates light emission and iridescence through liquid crystal self-assembly of cellulose nanocrystal-template silica approach is herein presented. These materials containing Rhodamine 6G were obtained as freestanding composite films with a chiral nematic organization. The scanning electron microscopy confirms that the cellulose nanocrystal film structure comprises multi-domain Bragg reflectors and the optical properties of these films can be tuned through changes in the relative content of silica/cellulose nanocrystals. Moreover, the incorporation of the light-emitting compound allows a complementary control of the optical properties. Overall, such findings demonstrated that the photonic structure plays the role of direction-dependent inner-filter, causing selective suppression of the light emitted with angle-dependent detection.

Recyclable luminescent carbon dots nanopaper for flexible electronics

“…One peak for the pure NFC-based nanopaper can be seen around 430 nm, with a shoulder peak appearing around 502 nm (figure 6(C)). The 430 nm peak corresponds to intrinsic emissive behavior of NFC [24]; while the peak ∼502 nm is due to the fluorescence properties of NFC (range of 500-600 nm) caused by structural property of the material and are independent of the presence of lignin [25].…”