Search

The development of amorphous films with a wide transmission window and high refractive index is of growing significance due to the strong demand of integrating functional nanoparticles for the next-generation hybrid optoelectronic films. High-index TeO2-based glass films made via the sol–gel process are particularly suitable as their low temperature preparation process promises high compatibility with a large variety of nanoparticles and substrates that suffer from low thermal stability. However, due to the lack of in-depth understanding of the mechanisms of the formation of undesired metallic-Te (highly absorbing species) in the films, the preparation of high-transmission TeO2-based sol–gel films has been severely hampered. Here, by gaining insight into the mechanistic chemistry of metallic-Te formation at different stages during the non-hydrolytic sol–gel process, we identify the chemical route to prevent the generation of metallic-Te in a TeO2-based film. The as-prepared TeO2-based film exhibits a high transmission that is close to the theoretical limit. This opens up a new avenue for advancing the performance of hybrid optoelectronic films via incorporating a large variety of unique nanoparticles. Refereed/Peer-reviewed

Nanostructured YAG:Nd³⁺ is an interesting material with a wide range of applications. In this paper, we report the fabrication of luminescent YAG:Nd³⁺ nanoparticles via a simple template-assisting nano-casting technique. By optimizing the synthetic parameters, bead-like hollow YAG:Nd³⁺ nanoparticles with nano-porous walls were successfully prepared. Their porous and hollow structures, and strong photoluminescence in the "Human Optical Window" make the YAG:Nd³⁺ nanoparticles promising candidates for in-vivo applications.

An AIE-active polytriazole coated fibre tip sensor was developed to detect picric acid with its detection limit down to 100 ppb. The fibre sensor requires an analysis time of only a few minutes and shows strong photostability and high reusability, and is promising for remote sensing of explosives in dangerous environments.

In this paper, a novel and efficient approach to digital optical data storage using rare-earth ion doped inorganic insulators is demonstrated. More specifically, the nanocrystalline alkaline earth halide BaFCl: Sm is shown to hold great potential for multilevel optical data storage. Proof-of-concept demonstrations show that these phosphors could be used for rewritable, multilevel optical data storage down to the physical dimensions of a single nanocrystal. Multilevel information storage is based on the highly-efficient and reversible conversion of Sm3+ to Sm2+ ions upon exposure to UV-C light. The stored information is efficiently read-out by employing the photoluminescence of the Sm2+ ions in the nanocrystals, with the signal strength being dependent on the UV-C intensity used during the write step. This serves as the mechanism for multilevel data storage in the individual nanocrystals. This data storage platform has the potential to be extended to 2D and 3D memory for storage densities that could approach tera- or even petabyte/cm(3) levels. Refereed/Peer-reviewed

Structural design is of great importance to the performance of photocatalysts in environmental remediation. Therefore, micro/nanofibrous morphology and nanoporous local structures have been found to be beneficial to improve the photocatalytic activity. In this investigation, we report the design and fabrication of flexible and thermal stable nanoporous SiO2–TiO2 composite fibers as efficient photocatalysts. Combining electrospinning and modified Stober techniques, core-shell and mesoporous SiO2 fibers with high flexibility were fabricated and employed as the scaffold for supporting TiO2 nanoparticles. A nanoporous shell of TiO2 nanoparticles was then muffled over the SiO2 fibers to form core@dual-shell SiO2–TiO2 composite fibers with hierarchically porous structure, which were conveniently patterned into a nonwoven, recyclable film. This nonwoven film exhibits better photocatalytic activity for Rhodamine B degradation under UV irradiation compared with some other TiO2-based materials reported in recent years.

Nanostructured YAG:Nd³⁺ is an interesting material with a wide range of applications. In this paper, we report the fabrication of luminescent YAG:Nd³⁺ nanoparticles via a simple template-assisting nano-casting technique. By optimizing the synthetic parameters, bead-like hollow YAG:Nd³⁺ nanoparticles with nano-porous walls were successfully prepared. Their porous and hollow structures, and strong photoluminescence in the "Human Optical Window" make the YAG:Nd³⁺ nanoparticles promising candidates for in-vivo applications.

Novel approaches for digital data storage are imperative, as storage capacities are drastically being outpaced by the exponential growth in data generation. Optical data storage represents the most promising alternative to traditional magnetic and solid-state data storage. In this paper, a novel and energy efficient approach to optical data storage using rare-earth ion doped inorganic insulators is demonstrated. In particular, the nanocrystalline alkaline earth halide BaFCl:Sm is shown to provide great potential for multilevel optical data storage. Proof-of-concept demonstrations reveal for the first time that these phosphors could be used for rewritable, multilevel optical data storage on the physical dimensions of a single nanocrystal. Multilevel information storage is based on the very efficient and reversible conversion of Sm³⁺ to Sm²⁺ ions upon exposure to UV-C light. The stored information is then read-out using confocal optics by employing the photoluminescence of the Sm²⁺ ions in the nanocrystals, with the signal strength depending on the UV-C fluence used during the write step. The latter serves as the mechanism for multilevel data storage in the individual nanocrystals, as demonstrated in this paper. This data storage platform has the potential to be extended to 2D and 3D memory for storage densities that could potentially approach petabyte/cm³ levels. Refereed/Peer-reviewed

Structural design of photocatalysts is of great technological importance for practical applications. A rational design of architecture can not only promote the synthetic performance of photocatalysts but also bring convenience in their application procedure. Nanofibers have been established as one of the most ideal architectures of photocatalysts. However, simultaneous optimization of the photocatalytic efficiency, mechanical strength, and thermal/chemical tolerance of nanofibrous photocatalysts remains a big challenge. Here, we demonstrate a novel design of TiO2-SiO2 composite fiber as an efficient photocatalyst with excellent synthetic performance. Core-shell mesoporous SiO2 fiber with high flexibility was employed as the backbone for supporting ultrasmall TiO2 nanowhiskers of the anatase phase, constructing core@double-shell fiber with luffa-sponge-like appearance. Benefitting from their continuously long fibrous morphology, highly porous structure, and completely inorganic nature, the TiO2-SiO2 composite fibers simultaneously possess high photocatalytic reactivity, good flexibility, and excellent thermal and chemical stability. This novel architecture of TiO2-SiO2 glass composite fiber may find extensive use in the environment remediation applications.

TiO2-based micro/nano fibres with secondary hierarchical structure have been extensively studied concerning a wide range of applications. However, simultaneous optimization of the flexibility and thermal stability of these materials still remains a big challenge. In this investigation, the successful fabrication and characterization of TiO2–SiO2 composite micron fibers with both high flexibility and excellent thermal stability are reported. Electrospun flexible SiO2 fibers were used as the scaffold for supporting TiO2 nanostructures. Three distinguished layers of porous SiO2, anatase TiO2 nanoparticle and rutile TiO2 nanorods were muffled over the SiO2 fibers stepwise, forming a unique core@multi-shell architecture with hierarchical structure. Such elaborately designed core@multi-shell TiO2–SiO2 fibers present high flexibility, excellent thermal stability, large specific surface area and high porosity. Moreover, they are easy to be patterned into nonwoven film with hierarchically porous structure, which is promising for many applications. We evaluate the water purification performance of the TiO2–SiO2 nonwoven film with Rhodamine B as a model organic pollutant. Efficient removal of Rhodamine B from water was implemented via simple filtration under UV irradiation, and regeneration of the photocatalytic functionality of the film from organic contamination was conveniently realized merely through calcination.