ZnO B2O3 Research Articles

Sm3+-doped CsPbBr3 NCs glass: A luminescent material for potential use in lighting engineering

Since being synthesized, CsPbX3 (X = Cl, Br or I) quantum dots (QDs) have gained increased interest due to their superior performances in photovoltaic applications. Herein, Sm3+-doped CsPbBr3 nanocrystallines (NCs) were successfully prepared in zinc borosilicate sodium (ZnO–B2O3–SiO2–Na2CO3, ZBSN) glass, and the as-prepared glass exhibited a strong red emission, which was attributed to the effects of the energy level transitions in Sm3+. Importantly, white light-emitting diodes (W-LEDs) were prepared by combining the glass with a blue InGaN chip, eliminating the need for a red phosphor to provide the red light, and white light was generated with a high colour rendering index (CRI: 82.6), a low correlated colour temperature (CCT: 4455 K) and colour coordinates in the white light region (0.3547, 0.3234). The glasses show excellent stability at 85 °C and 85% RH. Therefore, the Sm3+-doped CsPbBr3 NCs glass can be used as a colour converter for application in lighting engineering.

Microstructures and magnetic properties of low temparature sintering NiCuZn ferrite ceramics for microwave applications

Polycrystalline (Ni0.2Cu0.2Zn0.6O)1.03(Fe2O3)0.97 (NiCuZn) ferrite ceramics with low ferromagnetic resonance (FMR) line width (ΔH) and high saturation magnetization (4πMs) were synthesized at low sintering temperatures by adding Bi2O3–ZnO–B2O3 (BZB) glass additives. Furthermore, phase compositions, microstructures, and magnetic properties of the low-temperature-sintered NiCuZn ferrite ceramics were systematically analyzed. First, X-ray diffraction patterns showed that BZB glass has no obvious effect on phase structure of NiCuZn ferrites. Moreover, scanning electron microscopy images revealed that BZB glass can dramatically enhance grain growth and densification of the ferrites. More importantly, due to grain growth and reduction of porosity, ΔH of the NiCuZn ferrite sintered at 870 °C decreased significantly from 521.2 Oe to 150.5 Oe. Moreover, compact and uniform NiCuZn ferrites possessed high saturation magnetization (4πMs = ~4267 Gauss), reduced coercivity (Hc = ~92.2 A/m), and large saturation flux density (Bs = ~269.1 mT). The above mentioned results indicated that low-melting point BZB glass is an optional sintering aid to promote grain growth and enhance gyromagnetic properties of NiCuZn ferrites sintered at low temperature.

Synthesis, physical, structural and shielding properties of newly developed B2O3–ZnO–PbO–Fe2O3 glasses using Geant4 code and WinXCOM program

New zinc lead borate glasses with (50B2O3–10ZnO–(40 − y) PbO)–yFe2O3: 0 ≤ y ≤ 10 wt%) composition were synthesized by the conventional melt-quench technique. The amorphous nature of the glasses was tested by using X-ray diffraction spectroscopy. FTIR spectra for the glasses were recorded in the range of 4000–400 cm−1. Physical properties of the proposed glasses were evaluated. The mass attenuation coefficients (μ/ρ) for the glasses were calculated by the Geant4 simulation toolkit code and XCOM software within the photon energy range 365–2510 keV. Different γ-ray shielding parameters such as half-value layer, tenth value layer, and transmission fraction for the proposed glasses were evaluated using the obtained values of the (μ/ρ). Results reveal that for 1 cm glass thickness, the (50B2O3–10ZnO–30PbO)–10Fe2O3 sample has the highest transmission, due to the lower amount of Pb, and thus poorer shielding capability among the other glass samples. In addition, the probabilities of γ-ray interaction with the studied glasses were investigated.

Microstructures and dielectric properties of (Na0.5Bi0.5)0.775Ba0.225Ti0.775Sn0.225O3 relaxor ferroelectric with Bi2O3–B2O3–ZnO glass addition

To further manipulate the dielectric properties of (Na0.5Bi0.5)0.775Ba0.225Ti0.775Sn0.225O3 ceramics, (Na0.5Bi0.5)0.775Ba0.225Ti0.775Sn0.225O3 − x wt% Bi2O3–B2O3–ZnO (BBZ) ceramics were prepared via a conventional solid state reaction method, whilst the effect of BBZ glass content on dielectric and ferroelectric properties was investigated. In XRD patterns, the minimal secondary phase of Zn3(BO3)2 can be detected in these compounds when x > 5. With the addition of BBZ glass, diffuse phase transition behavior (DPT) and the high temperature stability of permittivity were enhanced. When x = 7, a high permittivity of 1600 ± 15%, from ~ 50 to ~ 475 °C was obtained. Additionally, a high Wd of 1.4 J/cm3 and 𝜂 of 75.5% (measured at 150 kV/cm) were achieved due to the enhanced Pm of 24 μC/cm2. This work demonstrated that the study on (Na0.5Bi0.5)0.775Ba0.225Ti0.775Sn0.225O3 ceramics with BBZ glass addition providing an adequate strategy to enhance Pm.

The Structure of Binary and Iron-Containing ZnO–B2O3 Glass by IR, Raman, and Mössbauer Spectroscopy

The structure of binary xZnO–(100–x)B2O3 glass and iron-containing, 2.5Fe2O3–97.5[xZnO–(100–x)B2O3] glass with x = 40, 45, 50, and 55 mol % obtained by the melt quenching method is studied by the methods of vibrational and Mossbauer spectroscopy. It is shown that the regularities of the transformation of the local glass structure as the function of zinc oxide content are the same for the glass of both series. A relatively small addition of iron oxide results in changing glass structure on the level of superstructural groups and to the distribution of trigonal basic borate units. The concentrations of di- and trivalent iron atoms are almost independent of the composition of the glass matrix while the coordination state of Fe3+ ions is a function of the zinc oxide content in the studied glass.

Enhanced Sintering Behaviour and Microwave Dielectric Properties of CaLa4Ti4O15 Ceramics with ZnO–B2O3 Addition

Effects of ZnO-B2O3 (ZB) addition have been investigated on the sintering behavior, structure and microwave dielectric properties of CaLa4Ti4O15 ceramics. The sintering temperature of CaLa4Ti4O15 ceramics with a very small amount of ZB addition such as 0.2 and 0.5% is obviously reduced from 1550 to 1375°C, and the sintering temperature range is significantly broadened to 1350–1450°C. With the increase of ZB addition, the secondary phases of CaLa4Ti5O17 and LaBO3 are observed in these ceramics. Not only sintering behavior but also microwave dielectric properties of CaLa4Ti4O15 ceramics have been enhanced by a small amount of ZB addition. Excellent microwave dielectric properties of e = 42.7, Qf = 46.678THz, τf = –3.5 ppm/°C are achieved for the CaLa4Ti4O15 ceramics with 0.5% ZB addition sintered at 1375°C.

Effects of Bi2O3–ZnO–B2O3–SiO2 glass addition on the sintering and microwave dielectric properties of ZnZrNb2O8 ceramics for LTCC applications

A novel low-temperature sinterable microwave dielectric ceramic was successfully developed by adding low-melting-point Bi2O3–ZnO–B2O3–SiO2 (BBSZ) glass to ZnZrNb2O8 (ZZN) ceramic. The influence of BBSZ glass on the densification behavior and microwave dielectric properties of ZZN ceramic was systematically investigated by means of an X-ray diffractometer, a scanning electron microscope and a network analyzer. By adding an appropriate amount of BBSZ glass into ZZN ceramic, the sintering temperature was lowered to 950 °C, indicating that BBSZ glass was an effective firing agent for ZZN ceramic. Furthermore, favorable microwave dielectric properties of ɛr = 32.5, Q×f = 38,400 GHz and τf = − 51 ppm/°C were yielded in the ZZN sample with 6 wt% BBSZ glass addition, simultaneously maintaining uniform and compact microstructure. The chemical compatibility between the present composite and Ag electrode was also investigated for commercial applications.

Sintering behavior and microwave dielectric properties of low-loss Li2Mg3TiO6 ceramics doped with different glass agents

Abstract The Li2Mg3TiO6 ceramics doped with ZnO B2O3 SiO2 (ZBS)/Li2O B2O3 SiO2 (ZBS) glass were synthesized through the conventional solid-state reaction route. The phase compositions, microstructures, sintering characteristics and microwave dielectric properties of Li2Mg3TiO6-xwt%ZBS and Li2Mg3TiO6-xwt%LBS (0 ≤ x ≤ 8) were investigated. With the increase of low-melting ZBS/LBS glass, the densification of Li2Mg3TiO6 ceramics was improved significantly through the mechanism of liquid phase sintering. The addition of ZBS/LBS glass could effectively lower the sintering temperature from 1350 °C to 1025 °C/1050 °C and had slightly influences on microwave dielectric properties of Li2Mg3TiO6 ceramics. The dielectric constant ɛr and Q×f values correlated with bulk density strongly. The temperature coefficient of resonant frequency (τf) was reduced by adding ZBS/LBS glass, due to the formation of the second phase MgSiO4. Compared with Li2Mg3TiO6-4wt%LBS sintered at 1050 °C, Li2Mg3TiO6 ceramics with 4 wt% ZBS glass sintered at 1025 °C had higher densification and more uniform grain morphology, which displayed excellent microwave dielectric properties of ɛr∼13.35, Q×f∼138,800 GHz and τƒ∼-31.84 ppm/°C.

Low-Temperature Co-Firing Ceramic Li2Zn3Ti4O12 Modified by Li2O–ZnO–B2O3 Eutectic Additive

Amaterial sintering at temperature 950°C for the technology of low-temperature co-firing ceramic used in the production of electronic components was developed in the system Li2O–ZnO–TiO2. The effect and method of synthesizing the eutectic sintering additive content in the system Li2O–ZnO–B2O3 on the compaction process and the dielectric properties of the obtained material were studied. The developed ceramic is characterized by the permittivity e = 17.7 and dielectric Q-factor 407 MHz.

Calculations of defect structures and spin Hamiltonian parameters of copper in (70 − x)Bi2O3–xLi2O–30 (ZnO–B2O3) glasses at different compositions

Defect structures and spin Hamiltonian parameters (SHPs) and the corresponding composition dependencies are quantitatively analyzed for divalent copper in ([Formula: see text])Bi2O3–[Formula: see text]Li2O–30(ZnO–B2O3) ([Formula: see text] mol.%) glasses by means of the relevant perturbation formulas of an octahedral 3d9 cluster with tetragonal elongation distortion. The [CuO6][Formula: see text] groups are subject to the moderate tetragonal elongation distortions of 4% due to the Jahn–Teller effect. The cubic crystal-field (CF) parameter, orbital reduction factor, tetragonal elongation ratio and core polarization constant exhibit respective piecewise linear functions of Li2O composition [Formula: see text], which suitably account for the experimental optical spectra and the SHPs at various compositions. Mechanisms of these composition dependencies for the related quantities can be explained as the variations of immediate CFs strength and copper–oxygen electron cloud admixtures with increasing Li2O composition.

Low temperature sintering and microwave dielectric properties of Li2ZnTi3O8–TiO2 ceramics doped with BaO–B2O3–ZnO glass

A low temperature co-fired ceramic (LTCC) material of Li2ZnTi3O8–TiO2 (L2ZT3–TiO2) doped with BaO–B2O3–ZnO (BBZ) glass were prepared by conventional solid-state method. The effects of BBZ glass on the phase composition, microstructure, and microwave dielectric properties were investigated. The results indicated that BBZ glass as a sintering aid could effectively reduce the sintering temperature of L2ZT3–TiO2 ceramic below 950 °C. The XRD patterns indicated that L2ZT3–TiO2 ceramic consisted of Li2ZnTi3O8 and TiO2 phases. BBZ glass addition did not change the phase composition. In addition, the SEM demonstrated that BBZ glass could significantly improve the grain growth and densification. The sintering mechanism was analyzed through the wetting behavior and the activation energy (Ea). When added 2.5 wt% BBZ glass, the average activation energy reduced from 492.38 ± 139.03 to 370.69 ± 20.98 kJ/mol, which indicated that the BBZ glass not only effective lowered the sintering temperature but also promoted the sintering process. The L2ZT3–TiO2 ceramic with 2.5 wt% BBZ sintered at 925 °C for 4 h had excellent microwave dielectric properties of er = 26.3, Q × f = 36,554 GHz and τf = − 4.16 ppm/°C. In addition, the good chemical compatibility of this material with Ag electrode could make it as a potential candidate for LTCC technology.

Role of Mn2+ ions on optical and luminescent properties of CaF2–Y2O3–ZnO–B2O3–SiO2 glasses

MnO doped CaF2–Y2O3–ZnO–B2O3–SiO2 glasses were synthesized. Different physical parameters of these glass materials such as density, molar volume, electronegativity, optical basicity and refractive index were calculated. The glass transition and glass crystallization temperatures of these glasses were measured by DTA analysis. The mechanical properties such as Young’s modulus, Shear modulus, Bulk modulus, Poisson’s ratio and microhardness of these materials were also calculated. Different characterization such as FT-IR, ESR, DC conductivity, optical absorption and photoluminescence were carried out on the prepared glass samples. ESR studies of these glass materials exhibited sextet at lower concentrations of MnO. The optical bandgap, Urbach energy, transition probability and emission cross section of these glass materials were calculated. Semiconducting nature of these glass materials was also observed due to the significant increase in BO3 and MnO6 units with increasing concentration of MnO. Optical absorption studies revealed that the increase in intensity of different octahedral peaks were due to the increase in concentration of MnO. Photoemission occurs around 545 to 567.3 nm suggested that the emission was red-shifted for higher MnO concentration and green-shifted for lower MnO concentration.

Investigations on structural, optical and magnetic features of vanadyl ions in PbO–CaO–ZnO–B2O3 glasses

Investigations on structural, optical and magnetic features of vanadyl ions in PbO–CaO–ZnO–B2O3 glasses

Role of Mn2+ ions on optical and luminescent properties of LiF–Sb2O3–ZnO–B2O3–SiO2 glasses

MnO doped LiF–Sb2O3–ZnO–B2O3–SiO2 glasses were synthesized by melt quenching technique. Different physical parameters such as density, molar volume, electronegativity, optical basicity and refractive index were calculated. The non-crystalline nature of the samples was confirmed by XRD analysis. SEM images projected that the prepared glass materials were contain well defined and indiscriminately allocated grains. The chemical analysis of these materials was studied by energy dispersion spectrum. The glass transition and glass crystallization temperatures of the glasses were recorded by DTA. FT-IR, Raman and ESR studies were also carried out on the prepared glass samples. The optical absorption reports of these glass materials have suggested that the octahedral tendency of Mn2+ ions increases with increasing concentration of MnO. The optical bandgap, Urbach energy, transition probability and emission cross section of these glass materials were calculated. Photoluminescence studies were also performed on the glass samples. The outcomes on all the investigations of these glasses have suggested that the Mn2+ ions predominantly occupy octahedral sites at higher concentrations of MnO.

Structure and microwave dielectric properties of Zn0.9Mg0.1TiO3–Zn0.15Nb0.3Ti0.55O2 ceramics with ZnO–B2O3–SiO2 glass

(1 − x)Zn0.9Mg0.1TiO3–xZn0.15Nb0.3Ti0.55O2 ((1 − x)ZMT–xZNT) (x = 0.100, 0.125, 0.150, 0.175, 0.200) ceramics were prepared at 900 °C by conventional mixed-oxide method. The phase content, microstructure and microwave dielectric properties had been investigated in detail. Rietveld refinement shows the coexistence of Zn0.9Mg0.1TiO3, Zn0.15Nb0.3Ti0.55O2, Zn(BO2)2 and Zn2TiO4 phases. With ZnO–B2O3–SiO2 (ZBS) glass added, the ceramics can be sintered well at 900 °C with a smaller grain size of 0.12 µm and a higher relative density (> 95%). The microwave dielectric properties are largely influenced by the phase composition according to mixture rule. A typical sample of 0.825ZMT–0.175ZNT ceramic with optimal dielectric properties (e r = 26.14, Q × ƒ = 27184 GHz, τ ƒ = − 3.46 ppm °C−1) was sintered at 900 °C for 4 h.

Investigation of Low‐Temperature Sintering Mechanism on BaONd2O3TiO2 Dielectric Ceramics with Li2OB2O3‐SiO2 and BaOZnOB2O3 Glasses

In this paper, the BaONd2O3TiO2 (BNT) ceramics are synthesized at low temperature with the assistance of Li2OB2O3SiO2 (LBS) and BaOZnOB2O3 (BZB) glasses. The influences of glasses on the sintering behavior, phase composition, microstructure, activation energy (Ea) on the BNT ceramics are studied in detail. The results show that a new phase, Ba2LiB5O10, is formed from the chemical reaction between LBS and BZB glasses. The sintering temperature of BNT ceramics can be effectively reduced by 450 °C due to the synergetic effect of LBS and BZB glasses and the appearance of Ba2LiB5O10 phase.

Structural and optical properties of Cr3+ embedded in a P2O5–B2O3–ZnO–BaF2–AlF3 fluoroborophosphate glasses

A new fluoroborophosphate glass doped with different amount of CrF3 were prepared via the melt-quenching method. These glasses were characterized by several techniques. The amorphous nature of the glass was evidenced by X-ray diffraction. Raman and FTIR were used to determine the functional groups composing the glass network. It was demonstrated the formation of B-O-P bond which replace some of the P-O-P bond and ensure the bonding of phosphorus and boron groups. Electron paramagnetic resonance (EPR), optical absorption and photoluminescence (PL) investigation have shown that Cr3+ ions have a preference to be located at weak field with distorted octahedral sites and they are mainly dispersed in phosphorus rich environment with fluorine or mixed fluorine/oxygen surrounding anions. Cr3+ sites dispersion was also evidenced by analyzing the temperature dependence of the PL spectra and the PL decay.

Sintering characteristic and microwave dielectric properties of 0.45Ca0.6Nd0.267TiO3–0.55Li0.5Nd0.5TiO3 ceramics with La2O3–B2O3–ZnO additive

The La2O3–B2O3–ZnO (LBZ) glass was proved to be an effective sintering aid of the 0.45Ca0.6Nd0.26TiO3–0.55Li0.5Nd0.5TiO3 (CNT–LNT) ceramics. The influence of LBZ glass on the phase composition, low temperature sintering process, microstructure, activation energy, and dielectric properties of CNT–LNT ceramics was investigated in detail. The LBZ glass induced an obvious decrease of the CNT–LNT ceramics sintering temperature from 1350 to 1000 °C due to the liquid phase formation, which reduced the activation energy (Ea) of the CNT–LNT ceramics. In addition, the near zero temperature coefficient of resonant frequency (τƒ) value was obtained by adding moderate quantity of LBZ glass. CNT–LNT + 5 wt% LBZ (CNT–LNT + 5L) ceramics sintered at 1000°C/4 h displayed good microwave dielectric properties of: er = 101.7, Q × f = 1560 GHz (f = 3.25 GHz) and τƒ = 2.3 ppm °C−1.

Low-firing Li0.42Zn0.27Ti0.11Mn0.1Fe2.1O4 ceramics modified with V2O5–ZnO–B2O3 glass addition for microwave device application

A novel V2O5–ZnO–B2O3 (VZB) glass was introduced into the Li0.42Zn0.27Ti0.11Mn0.1Fe2.1O4 (LiZnTiMn) ferrites for advancing low-temperature cofired ceramics technology and fabricating microwave ferrite devices by the multilayer process. The results reveal that the addition of VZB glass is an effective way to improve the densification, microstructure, and ferrimagnetic properties of the LiZnTiMn ferrites. The relationship among dopant amount, sintering mechanism, and structural distribution characteristic was established, tailoring the foundation of ferrimagnetic performance of low-temperature fired LiZnTiMn composites. The resulting VZB glass as flux promotes the microstructural uniformity and compactness and also provides the optimized physical properties of low-temperature sintered LiZnTiMn composites. An appropriate amount of VZB glass (~0.5 wt%) could enhance the saturation magnetization (from 52.2 to 72.3 emu/g) and remanence ratio of saturation induction (from 0.76 to 0.85) and reduce the coercivity of magnetic induction intensity (from 685 to 199 A/m) of the ferrite composites sintered at ~900 °C. Moreover, the ferromagnetic resonance linewidth of LiZnTiMn composites doped with 0.5 wt% VZB glass decreased from 860 to 195 Oe because of the combined effect of good uniformity and low porosity. Thus, with a low-temperature sintering process, the VZB glass could be a promising additive for achieving low-loss LiZnTiMn ferrite used in microwave devices.

Monte Carlo Design and Experiments on the Neutron Shielding Performances of B2O3–ZnO–Bi2O3 Glass System

Neutron shielding properties of (90 – x)B2O3–10ZnO–xBi2O3 glass systems (where x = 15, 20, 25 and 30 mol %) were investigated by Monte Carlo simulations (FLUKA and GEANT4) and experiments. Neutron mass removal cross sections, number of inelastic scattering, elastic scattering, and capture interactions were estimated by simulations. 241Am/Be neutron source was used for the neutron equivalent dose rate measurements. As a result, produced glass samples have fine neutron shielding capacity.