The orange luminescence of α-AlO under UV excitation is characterized by a 2.07-eV orange broadband emission that has not yet been elucidated. This emission is present in natural and synthetic crystals and powders, as well as in Be-treated samples. All orange-luminescent materials have low Fe concentration (mostly <1000 ppm) with traces of divalent cations, mostly Mg, or Be in Be-diffused material (dozens of ppm). Mg, Mn, and Be cations substitute for trivalent Al. To accommodate the charge deficit, several defects are created, including oxygen vacancies also called F centers. Indeed, our excitation spectra revealed the presence of several different F centers (F, F, and clustered F, F , F ) in those samples. However, the thermal stability and the measured luminescence lifetimes do not match with previously reported characteristics of isolated F centers. Based on our experiments, we suggest that a complex aggregate of two F centers (F ) trapped at divalent cations is a major cause of this uncommon microsecond lifetime emission, even if a variety of other defects, including Cr, V, or interstitial Al, are present.
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http://dx.doi.org/10.1002/bio.4757 | DOI Listing |
Spectrochim Acta A Mol Biomol Spectrosc
January 2025
College of Chemical and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022 China.
In recent years, it has become a development trend to design multi-application luminescent materials with rare earth ion doping. In this work, a series of Eu/Sm doped self-activated NaYMgVO (NYMVO) phosphors were synthesized through a simple high-temperature solid-state reaction method. Interestingly, due to the energy transfer (ET) from the matrix to the activators, the luminescence color of the phosphors changed from turquoise to orange-red and yellow-green under near-ultraviolet (n-UV) 365 nm excitation.
View Article and Find Full Text PDFInorg Chem
January 2025
Department of Chemistry, College of Sciences, Northeastern University, Shenyang, Liaoning 110819, China.
Copper-based halides have attracted significant attention due to their unique photophysical properties and diverse coordination configurations. However, enhancing water stability and modulating structural transitions in cuprous halide materials remain challenging. In this work, we successfully synthesized three copper(I) halides, (CHP)CuBr (L1, [CHP] = hexyltriphenylphosphonium), (CHP)CuBr (L2), and (CHP)CuI (L3), via solvent volatilization, demonstrating exceptional water stability even after 27 days of submersion.
View Article and Find Full Text PDFInorg Chem
January 2025
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China.
Mn-doped luminescent materials play a significant role in a variety of fields, including modern lighting, displays, and imaging. Mn exhibits a broad and adjustable emission, hinging on the local environment of the crystal field and the interaction of the 3d electrons. However, it is still a challenge to realize the precise control of the emission of Mn ions due to site-prior occupation in a specific lattice.
View Article and Find Full Text PDFJ Fluoresc
January 2025
Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, Andhra Pradesh, 522510, India.
In this work, the conventional melt quenching approach is used to synthesize the Pr doped NaF-BiO-BO-SiO (NBBS) glasses. The influence of Pr ions on their spectroscopic and structural characteristics in glass network is investigated. The amorphous nature of the samples has been amply verified by X-ray diffraction patterns.
View Article and Find Full Text PDFSmall
January 2025
College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, P. R. China.
Developing single-particle nanocomposite with aqueous-phase orthogonal multicolor phosphorescence or multimodal luminescence holds great significance for optical coding, anti-counterfeiting encryption, bioimaging, and biosensing. However, it faces challenges such as a limited range of emission wavelengths and difficulties in controlling the synthesis process. In this work, a conjugate structure manipulation integrated luminophor confinement strategy is proposed to prepare carbon dots@upconversion nanoparticles (CDs@UCNPs) featuring aqueous-phase orthogonal multicolor room-temperature phosphorescence-upconversion luminescence (RTP-UCL) through wet-chemical synthetic methods.
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