Cellulose Based Photonic Materials Displaying Direction Modulated Photoluminescence

• Published in: Frontiers in bioengineering and biotechnology Vol. 9; p. 617328
• Main Authors: Santos, Molíria V, Maturi, Fernando E, Pecoraro, Édison, Barud, Hernane S, Lima, Laís R, Ferreira, Rute A S, Carlos, Luís D, Ribeiro, Sidney J L
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 30-03-2021
• Subjects: bacterial cellulose nanocrystals; Bioengineering and Biotechnology; chiral nematic liquid crystal; iridescence; luminescence; modulated light emission; photonic materials; iridescence; rhodamine 6G; luminescence; chiral nematic liquid crystal; bacterial cellulose nanocrystals; modulated light emission; photonic materials
• ISSN: 2296-4185; 2296-4185
• DOI: 10.3389/fbioe.2021.617328

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.