Emission Color Manipulation in Transparent Nanocrystals‐in‐Glass Composites Fabricated by Solution‐Combustion Process

Abstract

Rational design and fabrication of multicolor fluorescent sources represent one of the significant challenges in the development of high‐performance solid‐state lighting, tunable coherent lasing, and full‐color display technologies. However, generation of simultaneous multicolor emission, especially white light generation with a wide color gamut is usually beyond the ability of a single material. Heterogeneous structures made by combinations of red, green, and blue emission building blocks are bulky, inefficient, complicated, and costly. Here reported is a bottom‐up strategy to generate simultaneous multicolor emission with continuous tunability in a single monolithic material based on the “nanocrystals‐in‐glass composite” (NGC) architecture. In this approach, a self‐sustained low‐temperature solution combustion process enables homogeneous solvent dispersion and eventually stable immobilization of multiple nanocrystals in transparent matrix. With transparency of up to 80%, further demonstrated is drawing of fiber from the melt of these combustion‐processed NGC materials. The optical spectra of the as‐drawn glass fiber can be precisely tuned and clustering is effectively suppressed. Moreover, the NGC materials exhibit remarkable anti‐thermal quenching behavior at temperatures of up to 200 °C. The bottom‐up strategy for NGC provides a versatile platform for the fabrication of high‐performance multifunctional fiber‐based devices for advanced applications in lasers, illumination, displaying, and biophotonics.

Tunable luminescence in Pr3+ single-doped oxyfluoride glass ceramic and fibers

“…However, the main obstacle to the preparation of such a material is the sophisticated design for simultaneous red, green, and blue (RGB) oscillations. 14 A single material with the goal of simultaneous RGB emission is closely related to the selection of luminescent activators. Rare earth (RE 3+ ) ions with excellent optical properties are deemed to be appropriate luminescent activated ions in the optical gain materials for laser generation.…”

Highly thermostable fluoride nanocrystal-in-glass composites (NGCs) for mid-infrared emission

“…Recently, nanocrystal-in-glass composite (NGC), composed of custom-tailored nanocrystals (NCs) embedded in transparent glass matrix, provides a strong platform to develop new classes of fiber materials. 21–23 Exploiting such a bottom-up strategy, efficient MIR emission in a robust oxide glass can be expected by coupling low-phonon NCs with MIR transparent amorphous matrix. Compared to the homogeneous glass, the hybrid NGC materials exhibit combined merits with optimal fluorescent performance derived from the incorporated low-phonon NCs and robust stability from the strong covalent network of suitable glass (Fig.…”

Tunable broadband photoluminescence from bismuth‐doped calcium aluminum germanate glasses prepared in oxidizing atmosphere

“…Furthermore, glass matrices offer highest compositional flexibility, from activator solubility to redox control and the tailoring of secondary properties (e.g., mechanical, chemical, or optical) 7,8 . Diverse light sources ranging from ultraviolet (UV) to infrared PL have been achieved with glasses, mostly using f–d or f–f electronic transitions in rare‐earth (RE) dopants 9–11 . The 4f electrons of the various RE species are fully shielded by the 5s 2 and 5p 6 electrons, which results in limited tunability of the PL characteristics of f–f transitions when exposed to variable glass chemical environments (with only some of the degenerate states depending on ligand symmetry and orbital distortion) 12 .…”

“…7,8 Diverse light sources ranging from ultraviolet (UV) to infrared PL have been achieved with glasses, mostly using f-d or f-f electronic transitions in rare-earth (RE) dopants. [9][10][11] The 4f electrons of the various RE species are fully shielded by the 5s 2 and 5p 6 electrons, which results in limited tunability of the PL characteristics of f-f transitions when exposed to variable glass chemical environments (with only some of the degenerate states depending on ligand symmetry and orbital distortion). 12 Therefore, alternative activator species are of interest beyond the REs for achieving broadband PL.…”