Red emission enhancement in BaYF:Eu phosphor nanoparticles by Bi co-doping.

Herein, we report the photoluminescence properties of Bi-sensitized BaYF5:10 mol%Eu nanoparticles. The emission spectra feature Eu peaks corresponding to transitions from the D0 excited to FJ (J = 1, 2, 3, 4) lower levels with two dominant emissions positioned in the orange-red (∼ 592 nm, D0 → F1) and deep-red (∼ 697 nm, D0 → F4) regions. Upon 265 nm excitation, the emission intensity increases with an increase of Bi concentration up to 20 mol%.

Luminescence Thermometry with Eu-Doped YMoO: Comparison of Performance of Intensity Ratio and Machine Learning Temperature Read-Outs.

Accurate temperature measurement is critical across various scientific and industrial applications, necessitating advancements in thermometry techniques. This study explores luminescence thermometry, specifically utilizing machine learning methodologies to enhance temperature sensitivity and accuracy. We investigate the performance of principal component analysis (PCA) on the Eu-doped YMoO luminescent probe, contrasting it with the traditional luminescence intensity ratio (LIR) method.

Nanosized Eu-Doped NaYSiO Oxyapatite Phosphor: A Comprehensive Insight into Its Hydrothermal Synthesis and Structural, Morphological, Electronic, and Optical Properties.

Detailed analysis covered the optical and structural properties of Eu-doped NaYSiO oxyapatite phosphors, which were obtained via hydrothermal synthesis. X-ray diffraction patterns of NaYSiO:xEu (x = 0, 1, 5, 7, 10 mol% Eu) samples proved a single-phase hexagonal structure ( (176) space group). Differential thermal analysis showed an exothermic peak at 995 °C attributed to the amorphous to crystalline transformation of NaYSiO.

Tuneable Red and Blue Emission of Bi-Co-Doped SrF:Eu Nanophosphors for LEDs in Agricultural Applications.

Tunable blue/red dual-emitting Eu-doped, Bi-sensitized SrF phosphors were synthesized utilizing a solvothermal-microwave method. All phosphors have cubic structure (- (225) space group) and well-distinct sphere-like particles with a size of ~20 nm, as examined by X-ray diffraction and transmission electron microscopy. The diffuse reflectance spectra reveal a redshift of the absorption band in the UV region as the Bi concentration in SrF: Eu phosphor increases.

Structure-Dopant Concentration Relations in Europium-Doped Yttrium Molybdate and Peak-Sharpening for Luminescence Temperature Sensing.

A set of Eu-doped molybdates, YxEuxMoO (x = 0.04; 0.16; 0.

Hydrothermal Synthesis and Properties of Yb/Tm Doped SrLaF Upconversion Nanoparticles.

We report the procedure for hydrothermal synthesis of ultrasmall Yb/Tm co-doped SrLaF (SLF) upconversion phosphors. These phosphors were synthesized by varying the concentrations of Yb (x = 10, 15, 20, and 25 mol%) and Tm (y = 0.75, 1, 2, and 3 mol%) with the aim to analyze their emissions in the near IR spectral range.

Exploiting High-Energy Emissions of YAlO:Dy for Sensitivity Improvement of Ratiometric Luminescence Thermometry.

The sensitivity of luminescence thermometry is enhanced at high temperatures when using a three-level luminescence intensity ratio approach with Dy- activated yttrium aluminum perovskite. This material was synthesized via the Pechini method, and the structure was verified using X-ray diffraction analysis. The average crystallite size was calculated to be around 46 nm.

All near-infrared multiparametric luminescence thermometry using Er, Yb-doped YAG nanoparticles.

This paper presents four new temperature readout approaches to luminescence nanothermometry in spectral regions of biological transparency demonstrated on Yb/Er-doped yttrium aluminum garnet nanoparticles. Under the 10 638 cm excitation, down-shifting near infrared emissions (>10 000 cm) are identified as those originating from Yb ions' F → F (∼9709 cm) and Er ions' I → I (∼6494 cm) electronic transitions and used for 4 conceptually different luminescence thermometry approaches. Observed variations in luminescence parameters with temperature offered an exceptional base for studying multiparametric temperature readouts.

Surface Plasmon Enhancement of Eu Emission Intensity in LaPO/Ag Nanoparticles.

A promising way to improve the performance of luminescent materials is to combine them with noble metal nanoparticles. Herein, a set of silver/europium-doped lanthanum orthophosphate (Ag/LaEuPO) nanostructures with different concentrations of silver nanoparticles were prepared and investigated. The presented overlap between the strongest europium (Eu) excitation line and the broad silver nanoparticle surface plasmon resonance makes the combination prospective for coupling.

Ratiometric temperature measurement using negative thermal quenching of intrinsic BiFeO semiconductor nanoparticles.

A strategy for optical nanothermometry using the negative thermal quenching behavior of intrinsic BiFeO semiconductor nanoparticles has been reported here. X-ray diffraction measurement shows polycrystalline BiFeO nanoparticles with a rhombohedral distorted perovskite structure. Transmission electron microscopy shows agglomerated crystalline nanoparticles around 20 nm in size.

Making Nd a Sensitive Luminescent Thermometer for Physiological Temperatures-An Account of Pitfalls in Boltzmann Thermometry.

Ratiometric luminescence thermometry employing luminescence within the biological transparency windows provides high potential for biothermal imaging. Nd is a promising candidate for that purpose due to its intense radiative transitions within biological windows (BWs) I and II and the simultaneous efficient excitability within BW I. This makes Nd almost unique among all lanthanides.

Pulsed Laser Deposited Dysprosium-Doped Gadolinium-Vanadate Thin Films for Noncontact, Self-Referencing Luminescence Thermometry.

Lanthanide-doped vanadate thin films offer (i) a promising platform for luminescence-based noncontact temperature sensing; (ii) ratiometric/self-referencing absolute measurements; (iii) exceptional repeatability and reversibility for multirun uses and a long life cycle; (iv) 2% K(-1) maximum temperature sensitivity (among the highest recorded for inorganic nanothermometers); (v) a temperature resolution greater than 0.5 K; and (vi) the potential for high-resolution 2D temperature mapping.