YVO4 Research Articles

CuMn2O4 anchored on mesoporous yttrium orthovanadate for the visible-light removal of hexavalent chromium ions in water

Recently, there has been significant interest in using one-dimensional nanomaterials for environmental cleanup in water sources, particularly for breaking down and eliminating harmful pollutants. Creating a reusable and effective photocatalyst poses a challenge in addressing semiconductor flaws such as instability and rapid recombination. This work discusses developing a highly responding photocatalyst by introducing varying quantities of CuMn2O4 (CMO) onto the surface of yttrium vanadate (YVO4) nanoparticles using the surfactant sol-gel method. The structures and morphology of these developed nanocomposites were verified using many characterization methods. The findings reveal that CMO is an electron trap within the dual system, which impedes charge carrier recombination and ameliorates photocatalytic performance. Their photocatalytic efficacy was evaluated through the photoreduction of Cr(VI) ions under visible illumination, revealing that adding CMO nanoparticles significantly boosts YVO4's photocatalytic activity. The Cr(VI) photoreduction follows a first-order reaction model. Among the tested photocatalysts, the 2.0 g/L dose of 9.0 % CMO-YVO4 demonstrated the most effective and reusable performance within 45 min. This sustained photocatalytic performance is credited to improved capture of light and effective transfer of charges resulting from the combination of CMO and YVO4.

Exploring silver oxide-loaded yttrium vanadate nanocomposite for visible-light-driven photooxidation of ciprofloxacin antibiotic in water

As a sooner or later risk, antimicrobial resistance due to the overuse of antibiotics is considered a nightmare facing humankind. The visible-light mineralization of antibiotic waste over nanoceramic photocatalysts is an innovative expectant method. Concerning this, nanostructured yttrium orthovanadate (YVO4) is grown via an adapted sol-gel process tracked by loading of 1.0–4.0 wt% of silver oxide (Ag2O) to form heterojunction nanocomposite of Ag2O/YVO4. The as-prepared heterostructures were applied for visible-light photoelimination of ciprofloxacin (CF) in water. The presence of Ag2O has enhanced both light absorbance and photogenerated carrier separation of YVO4. The 3.0 to 4.0 wt% loading of Ag2O designated the thinnest bandgap of 2.4 eV regardless of the minor decrease in their specific surface areas from 220 in bare YVO4 to 168 m2 g−1 for 3.0 % Ag2O/YVO4. The complete mineralization of CF over 3.0 % Ag2O/YVO4 was achieved after 60 min of light illumination at an optimized dose of 1.6 mg mL−1 and a reaction rate constant of 5.41 × 10−2 min−1. This improved photocatalyst has also a recyclable ability of ∼95 % of its initial photoactivity after the fifth experimental run. Therefore, the augmented light harvesting, surface texture, as well as superb carrier separation represent a key role in the performance of Ag2O/YVO4.

Optical properties and passive self Q-switching of floating zone grown Cr–Nd co-doped YVO4 crystal

Single crystals of Cr (0.7, 1.0, 1.4 and 2.0 at%) and Nd (0.7 at%) co-doped yttrium vanadate (YVO4) were grown by optical floating zone method. [100]-oriented elements were fabricated from the grown crystals for optical and lasing studies. The refractive index analysis revealed that the values of ordinary refractive indices (no) for 0.7, 1.0, 1.4 and 2.0 at% Cr doped samples were found to be almost constant except for a slight increase corresponding to 532 nm. But the extraordinary refractive indices (ne) was found to increase with Cr doping concentration and it is maximum at 1.4 at% for all the wavelengths. The thermal coefficient of ne and no increases slightly and becomes constant beynd 1.4 at% of Cr. The band gap of the crystal is polarization sensitive with the values in the range of 3.51–3.55 eV and 3.59–3.62 eV for electric field parallel and perpendicular to c axis, respectively. The band gap does not exhibit any significant change on Cr doping. The emission spectrum with excitation at 808 nm is characterized by three broad asymmetric bands centered at 896, 1064 and 1341 nm. The emission intensity for the peak around 1064 nm decreases with an increase in Cr due to a broad absorption around 1100 nm of Cr5+ ion and, therefore, this band is exploited for passive Q-switching in the crystal. Further, excitation at 400 nm of Cr band revealed that there is strong emission at 1064 nm, which may be explored for pumping the gain medium with solar radiation. Finally, a stable passive Q-switching at 1064 nm was demonstrated in [100] element fabricated from the gown crystal having 1.4 at% Cr. An output power of ∼108 mW having pulse-width ∼220 ns and repetition rate ∼239 kHz was achieved for a pumping of ∼14.6 W at 808 nm.

Observation of Extraneous Axial Cavity Modes of a Single-Mode Solid-State Laser Using Ultrahigh-Contrast Fabry–Perot Interferometry

Extraneous axial optical cavity modes produced by a single-mode frequency-doubled neodymium-doped yttrium orthovanadate (Nd:YVO[Formula: see text]) laser were observed in spectra obtained via ultrahigh-contrast Fabry–Perot interferometry. These modes, which are much weaker than the primary axial mode emission, are separated by [Formula: see text] GHz and display decreasing intensity with increasing shift from the primary laser line and with increasing laser output power. The possible presence of such modes in target sample spectra necessitates that caution be used in the interpretation of spectral peaks in laser spectroscopy studies, particularly Brillouin light scattering experiments. This work also showcases the remarkable capabilities of modern multipass Fabry–Perot interferometry in the detection of exceedingly weak optical signals shifted in frequency by only a few gigahertz from the primary laser emission line.

Polarized spectral properties and 2.3 µm laser performance of the Tm:YVO4 crystal

The polarized spectral properties and ∼2.3 µm high-power continuous-wave laser operation of Tm3+-doped yttrium orthovanadate crystal (Tm:YVO4) are reported. For the 3H4 → 3H5 transition, the stimulated-emission cross-section σSE is 1.01 × 10−20 cm2 at 2276 nm corresponding to a large emission bandwidth of 52 nm (for π-polarization). Pumped by a 794 nm laser diode, the 1.5 at.% Tm:YVO4 laser delivered 5.52 W at 2.29 µm with a slope efficiency of 19.9%, a laser threshold of 8.70 W, and a linear laser polarization (π). The Tm laser operated on the cascade scheme (on the 3H4 → 3H5 and 3F4 → 3H6 transitions) which was mainly responsible for the observed high laser slope efficiency. We also report on the first passively Q-switched Tm:YVO4 laser at 2.3 µm by employing porous nano-grained cuprous selenide (PNG-Cu2Se) as a saturable absorber. The shortest pulse duration and the highest single pulse energy amounted to 706 ns and 3.65 µJ, respectively, corresponding to a pulse repetition rate of 62.8 kHz.

Surface functionalized visible light-responsive yttrium orthovanadate for photocatalytic hydrogen production

Yttrium orthovanadate (YVO4), a wide-bandgap photocatalyst was tuned into a visible responsive material by anchoring an organic framework on the surface of YVO4 nanoparticles using polyethyleneimine (PEI). The surface organic framework was identified as the decomposed PEI derivatives with the carbonyl and carboxylic acid functional groups by the FTIR and XPS analyses. The top of the valence band (VB) was raised and the bottom of the conduction band was moved down; hence, the band gap of YVO4 was reduced to absorb the light in the visible region for all three synthesized samples, which was confirmed by DRS UV–Vis analysis. The functional groups facilitated more water molecules on the YVO4 surface via hydrogen bonding; hence, the YVO4 surface acquired superhydrophilicity. Among the three YI, YII, and YIII samples synthesized with three different calcination temperatures of 80, 260 and 400 °C respectively, YII showed many advantageous photocatalytic properties. The optimum loading of organic compounds obtained on YII surface at 260 °C, which improved the surface area, visible light absorption, hydrophilicity, and exciton's life. Hence, YII showed a better performance of 3.75 mmol h−1g−1cat H2 production than YI and YII. This work interestingly revealed the influence of calcination temperature on surface functionalization and the performance of catalytic materials.

Optimization of photoluminescence of Eu3+ doped YVO4 nanoparticles by green microwave synthesis

A detailed investigation of the europium-doped yttrium orthovanadate (YVO4:Eu3+) phosphorus prepared by fast and facile microwave synthesis was undertaken. The phase purity, morphology, particle distribution analysis, and photoluminescence were all thoroughly examined. The photoluminescence (PL) properties of the as-synthesized YVO4:Eu3+ nanostructures depend greatly on the synthesis parameters. The PL intensity of the nanomaterials increased when the Eu concentration, holding time, and amount of water used in the prepared phosphors were adjusted. The optimal europium doping concentration was 7 mol% for temperature holding times of 60 min, and 5 ml of water was used as the solvent. The emission intensity of Eu3+-doped YVO4 phosphors can be rationally modified by simply changing the pH of the solution or by employing different solvents. The phosphors studied were produced as nanoparticles with a very intense emission spectrum, making them good candidates for fluorescent lamps and light-emitting diodes (LEDs).

Study on all solid-state 213 nm laser Raman spectrometer

Due to the adverse effects formed by fluorescence interference difficult to remove, intense interest has been directed towards the development of techniques and instrumentation to inhibit fluorescence. When the wavelength of Raman excitation light is less than 250 nm, we can completely separate the fluorescence noise from the Raman features in the UV spectrum. Based on this, we describe a new deep UV Raman spectroscopy system composed of a compact acousto-optically Q-switched diode-pumped solid-state (DPSS) neodymium-doped yttrium vanadate laser and a UV Raman spectrometer. The laser is capable of producing ∼140 mW of 213 nm power quasi-continuous wave as 9.6 ns pulses at a 20 kHz repetition rate. The UV Raman spectrometer with the incident slit of 50 μm width is based on Littrow structure, of which the spectral resolution is better than 0.05 nm in the band of 211.5 nm ∼ 235.5 nm meeting the requirements of 10 cm−1 Raman spectral resolution. We effectively reduce the volume of the test system and improve the robustness of the test system. We measure the deep UV Raman spectra of solution methanol, which verified the feasibility and rationality of the system.

Synthesis and Basic Properties of Y1−xYbxVO4 Obtained by High-Energy Ball Milling and High-Temperature Treatment

The main objective of this work was to experimentally confirm that a continuous, substitutional solid solution of a general formula Y1−xYbxVO4 is formed in the pseudo-binary system YVO4–YbVO4, and to investigate its basic unknown properties as a function of composition for 0.00 < x < 1.00. To date, such a solid solution has been obtained and characterized to a limited extent, but only for a few selected compositions. This solution was obtained by a high temperature and, for the first time, using mechanochemical methods. For the solution obtained by the high-energy ball-milling method, unknown physicochemical properties were established over its entire range of homogeneity. The solution was synthesized from mixtures of yttrium orthovanadate (V) with ytterbium (III) orthovanadate (V) of different compositions and investigated by XRD, IR, SEM, and UV-Vis(DRS) methods. It was found that Y1−xYbxVO4 crystallizes in a tetragonal system. The results confirmed that the solid solution Y1−xYbxVO4 has a structure of YVO4 and YbVO4, and its structure is composed of YbO6 and YO6 octahedrons and VO4 tetrahedrons. Moreover, if the parameter (x) in the solid solution Y1−xYbxVO4 increases, its crystalline lattice contracts and the value of the energy gap decreases. This solid solution is stable in the air atmosphere at least up to ~1500 °C. The estimated band gap for this solid solution indicates that it belongs to the semiconductors.

Silver vanadate-coupled yttrium orthovanadate nanocomposite: An improved photocatalyst for amended visible-light-driven hydrogen evolution

The synthesis of yttrium orthovanadate (YVO4) by surfactant-aided sol-gel method is presented in this work. To enhance the visible-light activity of YVO4, 4.0–16.0 wt % of silver vanadate (AVO) nanoparticles were coupled by simple impregnation. The formed nanocomposites were applied for hydrogen (H2) production by photocatalytic reaction in a glycerol/water mixture with traces of platinum as a cocatalyst. The incorporation of 12.0 wt% AVO has boosted the H2 evolution by > 130 times (3.000 mmol g−1h−1) to the pure YVO4 (0.023 mmol g−1h−1). These outcomes were attributed to the efficient separation of photogenerated charges as well as bandgap reduction to 2.35 eV compared to 3.54 eV in pristine YVO4. The produced H2 could be furtherly enhanced to 3.750 mmol g−1h−1 by optimizing the photocatalyst amount at 2.0 g L−1. This innovative nanocomposite could also maintain its ability to produce 96% of its original H2 amount after the fifth regeneration cycle as well.

Yttrium vanadate coupled with cobalt ferrite nanocrystals for enhanced photocatalytic H2 production under visible light irradiation

Yttrium vanadate (YVO4) nanocrystals are synthesized by a modified sol-gel route followed by coupling with 4.0–16.0 wt% of cobalt ferrite (CoFe2O4) nanoparticles. The synthesized heterostructures were laboured for photocatalytic H2 generation in a water/glycerol system below visible light in the presence of platinum cocatalyst traces. The addition of CoFe2O4 nanoparticles has improved the physicochemical characteristics of YVO4 in terms of light harvesting and photoinduced charge separation. The 12.0 wt% CoFe2O4/YVO4 indicates the narrowest bandgap of 2.5 eV and the highest visible-light activity with a slight reduction of its surface area from 185 to 168 m2 g−1. Moreover, the H2 evolution rate has augmented utilizing this photocatalyst at 2.557 mmol g−1h−1 compared to 0.044 mmol g−1h−1 over the pure YVO4. Furthermore, the dose optimization of 12% CoFe2O4/YVO4 at 2.0 gL−1 has endorsed the photocatalytic generation of H2 to 3.389 mmol g−1h−1 with recyclability of 97% after the fifth cycle.

KGW and YVO4: two excellent nonlinear materials for high repetition rate infrared supercontinuum generation.

We present an experimental investigation of supercontinuum generation in potassium gadolinium tungstate (KGW) and yttrium vanadate (YVO4) crystals pumped with 210 fs, 1030 nm pulses from an amplified Yb:KGW laser operating at 2 MHz repetition rate. We demonstrate that compared to commonly used sapphire and YAG, these materials possess considerably lower supercontinuum generation thresholds, produce remarkable red-shifted spectral broadenings (up to 1700 nm in YVO4 and up to 1900 nm in KGW) and exhibit less bulk heating due to energy deposition during filamentation process. Moreover, durable damage-free performance was observed without any translation of the sample, suggesting that KGW and YVO4 are excellent nonlinear materials for high repetition rate supercontinuum generation in the near and short-wave infrared spectral range.

Decontamination of lithium disilicate ceramics using various photosensitizers, herbal and chemical disinfectants, and the effect of surface conditioners on bond strength values

AimTo assess and compare the antimicrobial efficacy of disinfectants on lithium disilicate ceramic (LDC) used in dental applications and shear bond strength (SBS) of LDC after using different conditioners hydrofluoric acid (HF), self-etching ceramic primers (SECP) and Neodymium-doped yttrium orthovanadate (Nd: YVO4). Materials and methodsOne hundred and twenty LDC discs were fabricated by auto-polymerizing acrylic resin using the lost wax technique. S. aureus, S. mutans, and C. albican were inoculated on thirty discs (n = 30 each). Each group was further divided into three subgroups based on different disinfecting agents used (n = 30) Group 1: Garlic extract, Group 2: Rose Bengal (RB) activated by PDT, and Group 3: Sodium hypochlorite (NaOCl). An assessment of the survival rate of microorganisms was performed. The remaining thirty samples were surface treated using three different LDC surface conditioners (n = 10) Group 1: HF + Silane (S), group 2: SECP, and Group 3: Nd: YVO4 laser+S. SBS and failure mode analysis were performed using a universal testing machine and stereomicroscope at 40x magnification, The statistical analysis was conducted using one-way ANOVA and Post Hoc Tukey test. ResultsGarlic extract, RB, and 2% NaOCl sample displayed comparable outcomes of antimicrobial potency against C. albicans, S aureus, and S. mutans (p > 0.05). Furthermore, SBS analysis showed HF+S, SECP, and Nd: YVO4+S exhibited comparable outcomes of bond strength (p > 0.05). ConclusionGarlic extract and Rose bengal activated by PDT can be contemplated as alternatives to the chemical agent NaOCl used for LDC disinfection. Similarly, SECP and Nd: YVO4 possess the potential to be used for the surface conditioning of LDC to improve the bond integrity with resin cement.

Upconversion Luminescence Response of a Single YVO4:Yb, Er Particle.

We present the results of the luminescence response studies of a single YVO4:Yb, Er particle of 1-µm size. Yttrium vanadate nanoparticles are well-known for their low sensitivity to surface quenchers in water solutions which makes them of special interest for biological applications. First, YVO4:Yb, Er nanoparticles (in the size range from 0.05 µm up to 2 µm), using the hydrothermal method, were synthesized. Nanoparticles deposited and dried on a glass surface exhibited bright green upconversion luminescence. By means of an atomic-force microscope, a 60 × 60 µm2 square of a glass surface was cleaned from any noticeable contaminants (more than 10 nm in size) and a single particle of 1-µm size was selected and placed in the middle. Confocal microscopy revealed a significant difference between the collective luminescent response of an ensemble of synthesized nanoparticles (in the form of a dry powder) and that of a single particle. In particular, a pronounced polarization of the upconversion luminescence from a single particle was observed. Luminescence dependences on the laser power are quite different for the single particle and the large ensemble of nanoparticles as well. These facts attest to the notion that upconversion properties of single particles are highly individual. This implies that to use an upconversion particle as a single sensor of the local parameters of a medium, the additional studying and calibration of its individual photophysical properties are essential.

Surface conditioning of PEEK post using Nd: YVO4 laser, photodynamic therapy, and sulfuric acid on the pushout bond strength to canal dentin

AimTo assess the push-out bond strength (PBS) of polyetheretherketone (PEEK) post-to-root dentin using post-surface conditioners i.e., Neodymium-doped yttrium orthovanadate (Nd: YVO4) and Riboflavin (RF) and Rose Bengal (RB) mediated photodynamic therapy (PDT) compared to sulfuric acid (SA). Materials and MethodsDecoronation of forty human single-rooted premolar teeth was performed. Followed by chamber opening, working length (WL) was established at 15 mm. Root canal preparation was completed using ProTaper Ni-Ti rotary system till F3 finishing file along with root canal disinfection. The canals were dried with paper cones followed by obturation using gutta-percha (GP) and AH sealer. Post space was prepared by drilling out 11 mm of GP using a Gates Glidden drill #3. PEEK posts were fabricated using the CAD-CAM system and then randomly allocated into 4 groups based on the post-surface conditioning (n = 10). Group 1: SA, group 2: PDT RF, group 3: PDT RB, and group 4: Nd: YVO4 laser. The PEEK post was then cemented in their respective canal. PBS and failure mode assessment were performed using a universal testing machine and stereomicroscope at 40x magnification. The SBS data set was subjected to a one-way analysis of variance (ANOVA) and Tukey's Post Hoc test at a significance level of 0.05. ResultsThe samples in group 4 (Nd: YVO4 laser) coronal third (7.99±0.24 MPa) demonstrated the highest PBS. The apical third of samples in group 1 PEEK post surface conditioned with SA (5.15± 0.52 MPa) exhibited the minimum values of PBS. Intergroup comparison analysis showed that samples in group 1 (SA), group 2 (RF activated by PDT), group 3 (RB activated by PDT), and group 4 (Nd: YVO4 laser) demonstrated comparable outcomes of bond scores (p>0.05) ConclusionNeodymium-doped yttrium orthovanadate (Nd: YVO4) and riboflavin and Rose bengal activated by photodynamic therapy (PDT) have been investigated as potential alternatives for the surface conditioning of PEEK (polyetheretherketone) posts.

Self-Raman 1176 nm Laser Generation from Nd:YVO4 Crystal by Resonator Cavity Coating

Crystal coating is an important process in laser crystal applications. According to the crystal characteristics of neodymium-doped yttrium vanadate (Nd:YVO4), its intrinsic parameters, and optical film design theory, Ta2O5 and SiO2 were selected separately as high and low refractive index materials. The optical properties and surface roughness of the films were characterized by OptiLayer and Zygo interferometers, and the effects of ion source bias on refractive index and surface roughness were investigated so that the optimal ion source parameters were determined. Optical monitoring and quartz crystal control were combined to accurately control the thickness of each film layer and to reduce the monitoring error of film thickness. The prepared crystal device was successfully applied to the 1176 nm laser output system.

Promoted visible-light-driven H2 production over hydrothermally synthesized YVO4 nanorods coupled with Pt/AgInS2 nanospheres

The curiosity of hydrogen (H2) production has become a vital substitute energy resource due to its lightweight, green, and renewability. The photocatalytic production of H2 from water over nanostructured semiconductors is a talented route. This study aims to synthesize yttrium vanadate (YVO4) nanorods by hydrothermal approach coupled with different amounts of tiny silver indium sulfide (AgInS2) nanospheres at 5.0–20.0 wt%). All samples were applied for visible-light photocatalytic evolution of H2 in a water-glycerol mixture. Physicochemical description of the prepared specimens exposes the impact of adding AgInS2 on structure, surface, and light harvesting properties. The addition of 15.0 wt% AgInS2 on YVO4's has slightly reduced the specific surface area from 170 to 160 m2 g−1, while the visible light absorbance is pointedly improved due to the significant bandgap energy reduction from 3.67 to 2.49 eV. The photogenerated H2 over 15% AgInS2/YVO4 and trace Pt deposits reached 3.344 mmol g−1h−1, which continued its recyclability for five runs at 96%. This effectual photogenerated H2 evolution is ascribed to the wide-ranged light absorbance and the efficient charge separation between AgInS2 and YVO4.

Self-Mixing Displacement Measured by a Two-Color Laser in 66-nm Steps

We demonstrate a new self-mixing interferometer (SMI) simultaneously working on two wavelengths, the fundamental at 1064 nm and the second harmonic at 532 nm delivered in the same beam. The beam is sent to the remote target in the usual way, and in the return path, two photodiodes detect the two self-mixing signals without crosstalk. As the source, we were able to use a diode-pumped neodymium-doped yttrium vanadate (Nd:YVO4 laser crystal) with potassium titanyl phosphate (KTP nonlinear crystal) two-color laser of a commercial pointer. With simple processing of the two self-mixing signals, we are able to obtain the interferometric signals <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\cos (2ks)$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sin (2ks)$ </tex-math></inline-formula> at 532 nm, from which the unambiguous measurement of arbitrary target displacement follows with counts in units of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda /8$ </tex-math></inline-formula> of the second-harmonic wavelength or 66 nm.

Gold-nanoparticles induced transition in YVO4 crystal: From saturable to reverse saturable absorption

The embedded gold (Au) nanoparticles (NPs) are synthesized inside the yttrium vanadate (YVO4) crystal by direct Au ion implantation. The formed Au nanospheres are with average diameter of ∼5 nm, generating a clear optical absorption band centered at 595 nm due to the localized surface plasmon resonance (LSPR). With the doping of Au NPs, the nonlinear optical properties of YVO4 crystal are also modified, endowing the substrate with new features. Using femtosecond open-aperture Z-scan investigation under variable laser intensities, the Au NPs-modified YVO4 exhibits saturable absorption (SA) property at moderate excitation irradiances due to the plasmonic effect of embedded Au NPs, whilst transits to reverse saturable absorption (RSA) under higher pump irradiances. As an example for practical applications, we demonstrate a 1-μm pulse laser generation utilizing Au NPs-embedded YVO4 crystal as the saturable absorber. This work suggests that ion beam synthesis of metallic NPs may be a suitable way to tailor properties of functional crystals to achieve diverse applications in optics.

Enhanced optical properties of yttrium aluminum garnet with the yttrium vanadate impurity phase

Yttrium aluminum garnet doped with europium with an additional impurity phase of yttrium vanadate doped europium has been prepared in different ways: synthesized by a sol-gel route and mechanically mixed in a mortar. The obtained samples were characterized by X-ray diffraction analysis, and scanning electron microscopy. Photoluminescence spectra were recorded to understand the role of the impurity phase in the garnet's optical properties. The impurity phase showed a significant contribution to the optical properties of Y3Al5O12:1%Eu.