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We report on efficient ZnO nanocrystal (ZnO-NC) emission in the near-UV region. We show that luminescence from ZnO nanocrystals embedded in a SiO2 matrix can vary significantly as a function of the annealing temperature from 450°C to 700°C. We manage to correlate the emission of the ZnO nanocrystals embedded in SiO2 thin films with transmission electron microscopy images in order to optimize the fabrication process. Emission can be explained using two main contributions, near-band-edge emission (UV range) and defect-related emissions (visible). Both contributions over 500°C are found to be size dependent in intensity due to a decrease of the absorption cross section. For the smallest-size nanocrystals, UV emission can only be accounted for using a blueshifted UV contribution as compared to the ZnO band gap. In order to further optimize the emission properties, we have studied different annealing atmospheres under oxygen and under argon gas. We conclude that a softer annealing temperature at 450°C but with longer annealing time under oxygen is the most preferable scenario in order to improve near-UV emission of the ZnO nanocrystals embedded in an SiO2 matrix.
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http://dx.doi.org/10.1186/1556-276X-8-517 | DOI Listing |
Regen Biomater
August 2025
College of Textiles & Clothing, Institute of Functional Textiles and Advanced Materials, Qingdao 266071, China.
Bacterial infection in the injured skin may threaten the wound repair and skin regeneration owing to aggravated inflammation. The multifunctional dressings with persistent antibacterial activity and improved anti-inflammatory capability are urgently required. Herein, a type of heterogeneous zinc/catechol-derived resin microspheres (Zn/CFRs) composed of zinc ions (Zn) and zinc oxide (ZnO) nanoparticles was developed to impart the methacrylamide chitosan (CSMA)-oxidized hyaluronic acid (OHA) hydrogel with a persistent Zn release behavior.
View Article and Find Full Text PDFInt J Biol Macromol
September 2025
School of Resource and Environmental Engineering, Jiangxi University of Science and Technology, Ganzhou, 341000, China; School of Resources and Civil Engineering, GanNan University of Science and Technology, Ganzhou, 341000, China.
Herein, organic/inorganic multiple adsorption sites were constructed on halloysite to intensify the selective adsorption performance of the adsorbent for Al(III) in rare earth solutions. The adsorption heat behavior and thermodynamics of the composite for different ion systems were investigated using microcalorimetry. The results showed that chitosan formed a mesoporous membrane on the acid-treated calcined halloysite (HalH) substrate through a strong electron interaction between the nitrogen atom of the amino group and the oxygen atom of SiO structure on HalH.
View Article and Find Full Text PDFMikrochim Acta
September 2025
Department of Public Health Laboratory Sciences, College of Public Health, Hengyang Medical School, University of South China, 28 Changsheng West Road, Hengyang, 421001, Hunan, China.
We systematically evaluated the DNA adsorption and desorption efficiencies of several nanoparticles. Among them, titanium dioxide (TiO₂) nanoparticles (NPs), aluminum oxide (Al₂O₃) NPs, and zinc oxide (ZnO) NPs exhibited strong DNA-binding capacities under mild conditions. However, phosphate-mediated DNA displacement efficiencies varied considerably, with only TiO₂ NPs showing consistently superior performance.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
September 2025
A.O. Kovalevsky Institute of Biology of the Southern Seas, Russian Academy of Sciences, Sevastopol, Russia.
The emergence of new types of pollutants and the increase of anthropogenic load on the environment provoked an increased interest of researchers to study the toxic effects of pollutants on living organisms. This study is devoted to investigate the physiological response of the Black Sea phytoplankton community to the effects of ZnO, CuO and TiO nanoparticles (NPs) of different concentrations by creating in vitro model microcosms. Trends of changes in the ratio between phytoplankton groups (cyanobacteria-picoeukaryotic algae-nano-microphytoplankton), species composition, growth rates and functional state of cells under the influence of the studied nanoparticles were revealed.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
Key Laboratory of Atomic and Molecular Physics & Functional Materials of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China.
Overcoming the persistent challenges of high operating temperatures and poor selectivity in metal oxide semiconductor (MOS) gas sensors, this work enhances defect sites in the sensing material through heterostructure construction and builds mesoporous architectures using MOF-derived carbon skeletons as templates. The synergistic effects of multiple mechanisms significantly improve gas-sensing performance, successfully fabricating a ZnO/PCS flexible room-temperature gas sensor with exceptional room-temperature DMF detection capabilities. The nitrogen-containing porous carbon skeletons (PCSs) template shows a stable mesoporous microstructure with large pore volume.
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