title: High-Stability, High-Efficiency Organic Monoliths Made of Oligomer Nanoparticles Wrapped in Organic Matrix.
abstract: Oligomer nanoparticles (OL NPs) have been considered unsuitable for solid-state lighting due to their low quantum yields and low temperature stability of their emission. Here, we address these problems by forming highly emissive and stable OL NPs solids to make them applicable in lighting. For this purpose, we incorporated OL NPs into sucrose matrix and then prepared their all-organic monoliths. We show that wrapping the OL NPs in sucrose significantly increases their quantum yield up to 44%, while the efficiency of their dispersion and direct solid-film remain only at ∼6%. We further showed ∼3-fold improved temperature stability of OL NP emission within these monoliths. Our experiments revealed that a physical passivation mechanism is responsible from these improvements. As a proof-of-concept demonstration, we successfully employed these high-stability, high-efficiency monoliths as color converters on a blue LED chip. Considering the improved optical features, low cost, and simplicity of the presented methodology, we believe that this study holds great promise for a ubiquitous use of organic OL NPs in lighting and possibly in other photonic applications.
authors.affiliation: Departments of Electrical and Electronics Engineering, Physics, and Chemistry, UNAM-National Nanotechnology Research Center, and Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey.
authors.forename: Zeliha
authors.initials: Z
authors.lastname: Soran-Erdem
authors.affiliation: Departments of Electrical and Electronics Engineering, Physics, and Chemistry, UNAM-National Nanotechnology Research Center, and Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey.
authors.forename: Talha
authors.initials: T
authors.lastname: Erdem
authors.affiliation: Departments of Electrical and Electronics Engineering, Physics, and Chemistry, UNAM-National Nanotechnology Research Center, and Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey.
authors.forename: Kivanc
authors.initials: K
authors.lastname: Gungor
authors.affiliation: Departments of Electrical and Electronics Engineering, Physics, and Chemistry, UNAM-National Nanotechnology Research Center, and Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey.
authors.forename: Jousheed
authors.initials: J
authors.lastname: Pennakalathil
authors.affiliation: Departments of Electrical and Electronics Engineering, Physics, and Chemistry, UNAM-National Nanotechnology Research Center, and Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey.
authors.forename: Dönüs
authors.initials: D
authors.lastname: Tuncel
authors.affiliation: Departments of Electrical and Electronics Engineering, Physics, and Chemistry, UNAM-National Nanotechnology Research Center, and Institute of Materials Science and Nanotechnology, Bilkent University , Ankara 06800, Turkey.|Luminous! Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 639798, Singapore.
authors.forename: Hilmi Volkan
authors.initials: HV
authors.lastname: Demir
keywords: fluorescent monoliths; light-emitting diodes; oligomer nanoparticles; organic crystalline host; solid-state lighting