Tuning Green to Red Color in Erbium Niobate Micro- and Nanoparticles

Abstract

Tetragonal Er0.5Nb0.5O2 and monoclinic ErNbO4 micro- and nanoparticles were prepared by the citrate sol–gel method and heat-treated at temperatures between 700 and 1600 °C. ErNbO4 revealed a spherical-shaped crystallite, whose size increased with heat treatment temperatures. To assess their optical properties at room temperature (RT), a thorough spectroscopic study was conducted. RT photoluminescence (PL) spectroscopy revealed that Er3+ optical activation was achieved in all samples. The photoluminescence spectra show the green/yellow 2H11/2, 4S3/2→4I15/2 and red 4F9/2→4I15/2 intraionic transitions as the main visible recombination, with the number of the crystal field splitting Er3+ multiplets reflecting the ion site symmetry in the crystalline phases. PL excitation allows the identification of Er3+ high-energy excited multiplets as the preferential population paths of the emitting levels. Independently of the crystalline structure, the intensity ratio between the green/yellow and red intraionic transitions was found to be strongly sensitive to the excitation energy. After pumping the samples with a resonant excitation into the 4G11/2 excited multiplet, a green/yellow transition stronger than the red one was observed, whereas the reverse occurred for higher excitation photon energies. Thus, a controllable selective excited tunable green to red color was achieved, which endows new opportunities for photonic and optoelectronic applications.

Study on the Structure, Morphology, Dielectric, and Piezoelectric Properties of Large-Grain (Ba0.85Sr0.15)1–xPbxTiO3 Ceramic System for 0.02 ≤ x ≤ 0.08

“…This finding reinforces the conclusion that the diffusion of all Pb 2+ ions occurred within the tetragonal (Ba 0.85 Sr 0.15 )TiO 3 lattice, giving rise to the establishment of a solid solution marked by a pristine perovskite structure. The crystal sizes and associated structural parameters of the samples were computed based on this diffraction data, with an uncertainty ranging from 5 to 10%, 39,40 and the ensuing findings will be elaborated upon in the subsequent section.…”

“…This method, as detailed in the reference, with an uncertainty ranging from 5 to 10%. 39,40,49 The total broadening of the peaks, represented by (β total ) is influenced by the combined effects of crystallite size (β size ) and microstrain (β strain ). The overall broadening observed in the X-ray diffraction peaks is a result of the interplay between these factors.…”

Reproductive performance of freshwater snail, Helisoma duryi under the effect of bulk and nano zinc oxide

“…Its nontoxic and eco‐friendly nature makes it particularly suited for environmental remediation, especially in freshwater aqueous environments where it demonstrates minimal toxicity to aquatic life despite high concentrations (Franklin et al, 2007). In water treatment, zinc oxide's catalytic activity under UV irradiation enables efficient degradation of organic pollutants (Bertrand et al, 2021), while in biology, its biocompatibility renders it invaluable for various biomedical applications such as drug delivery and antimicrobial coatings, owing to its ability to interact with biological systems without causing adverse effects (Fillmann et al, 2002). By elucidating these distinctions and applications, we underscore the multifaceted benefits of zinc oxide, emphasizing the importance of eco‐conscious material design and utilization.…”

“…The reproductive system serves as a crucial focal point in toxicity experiments due to its sensitivity to environmental stressors and toxic substances, as highlighted by the previous studies (Devesa et al, 2021;Franklin et al, 2007). Changes in reproductive parameters such as fecundity, fertility, and developmental abnormalities can provide early indicators of toxicity and adverse effects on overall organism health (Turner & Chislock, 2010).…”

Synthesis and Optical Characteristics of Gd0.96Eu0.01Sm0.01Tb0.01Er0.01Nb0.9Ta0.1O4 Ceramic Solid Solutions Prepared under Different Temperature Conditions

“…These powders provide the possibility of obtaining dense homogeneous materials with good mechanical characteristics at an optimal sintering temperature. For example, ceramics and thin films can be obtained [16][17][18][19]. High density and uniformity significantly increase the efficiency of luminescent materials, increasing the intensity of the glow due to their greater structural uniformity [3].…”