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Comprehensive Summary: A new gelator (BAzo‐Chol) comprising a diazocine core and two cholesterol units linked via carbamate groups has been designed and synthesized. Its gelation ability in several kinds of organic solvents is identified. Investigations with scanning electron microscopy (SEM), transmission electron microscopy (TEM), rheological measurements, and UV‐vis absorption and 1H NMR spectroscopy reveal that BAzo‐Chol can self‐assemble into elastically interpenetrating one‐dimensional nanostructures in organogels through a cooperative effect of the π‐π interactions, hydrogen‐bonding, and van der Waals forces. Moreover, the unconventional Z/E conformational transitions of these organogels, due to the inclusion of diazocine, endow the BAzo‐Chol gels with excellent photo‐responsive gel‐sol transition and remarkable visible light‐induced chromic properties. Lastly, due to its sensitive response to visible light accompanied by distinct changes in both colour and transparency of the gel‐sol transitions, the potential application of the current gelator in smart windows is signified. [ABSTRACT FROM AUTHOR]

Organic-inorganic nanocomposites (RF/VOX) based on resorcinol-formaldehyde carbon matrix enriched by vanadium nanoparticles were synthesized by sol-gel method coupled with pyrolysis treatment. The crystallite structure of the resulting sample was investigated by X-ray diffraction technique, which shows the change of the V2O5 phase to V2O3 one under the pyrolysis temperature effect and the presence of vanadium carbide V8C7 phase in sample pyrolyzed at 1000 °C. The X-ray diffraction analysis proves the appearance of the graphite phase in all samples. Microscopic images (transmission electron microscopy and scanning electron microscopy) indicate the presence of macroporous carbon enriched with vanadium oxide in the form of nanobelts. These structural observations strongly affect the electrical properties. The current-voltage curves exhibit the presence of non-linear behavior for samples RF/VOX-625 and RF/VOX-650 which is identified as negative differential resistance NDR phenomenon. This NDR behavior appears at applied voltages of 51 and 180 V for samples RF/VOX-625 and RF/VOX-650, respectively. The Joule heating effect and filament formation were estimated as the origin of NDR behavior. The conductivity of our samples can be modulated by applying current. The coexistence of these two behaviors makes our samples promising for threshold switching and oscillator circuits. [ABSTRACT FROM AUTHOR]

Novel Eu3+-doped Na5Zn2Gd(MoO4)6 triple molybdate phosphors were fabricated by the sol-gel method. The structure, morphology, and luminescent properties have been characterized by X-ray diffraction (XRD), thermogravimetric differential thermal analysis (TG-DTA), scanning electron microscopy (SEM), FTIR spectroscopy, and luminescence spectroscopy. The results indicated that the synthesized Na5Zn2Gd1−x(MoO4)6: xEu3+ phosphor consisted of a pure phase with monoclinic structure. Under excitation at 465 nm, the Na5Zn2Gd1−x(MoO4)6: xEu3+ phosphor exhibits an intensive red emission band around 610 nm corresponding to the transition of 5D0→7F2 which is much higher than that 5D0→7F1 at 594 nm, which was appropriate for a blue LED. According to the influence of the synthesis conditions, the phosphors showed the highest emission intensity when the doping concentration of Eu3+ was 25 mol.% and the molar ratio of citric acid to metal ions was 2:1. Na5Zn2Gd0.75(MoO4)6: 0.25 Eu3+ with the color coordinates (x = 0.658, y = 0.341) is a more stable red phosphor for blue-based white LEDs than the commercial Y2O2S: Eu3+ red phosphor (0.48, 0.50) due to its being closer to the NTSC standard values (0.670, 0.330). [ABSTRACT FROM AUTHOR]

This study investigates the synthesis, characterization, and application of ZnO/SnO2 nanocomposite (ZnO/SnO2 NC), focusing on their photocatalytic and antioxidant properties. The sol-gel technique was utilized for the synthesis of the ZnO/SnO2 NC. Subsequent characterization was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and UV-visible (UV-Vis) spectrophotometry. The XRD analysis indicated crystallite dimensions of 15 nm for ZnO/SnO2 and 21 nm for pure ZnO NPs. The photocatalytic efficiency was assessed by the degradation of Toluidine Blue (TB) and m-Toluidine Blue (m-TB) dyes. The ZnO/SnO2 NC demonstrated degradation rates of 99% for both TB and m-TB within 120 and 140 min of sunlight exposure, respectively. Furthermore, the scavenging activity of superoxide radicals was evaluated, with the ZnO/SnO2 NC exhibiting an Half-maximal inhibitory concentration (IC50) value of 48.12 µg∙mL− 1, compared to 60.03 µg∙mL− 1 for pure ZnO. This research highlights the potential of ZnO/SnO2 NC in environmental remediation and biomedical applications. [ABSTRACT FROM AUTHOR]

A sol-gel matrix was generated from S– and P-based acids to prepare a fire-retardant solution system for coating natural cotton fibers. The physical properties, surface morphology, and elemental composition of the coated samples were assessed using optical scanning electron microscopy. The thermal behavior of the coated samples was documented using TGA and VFT tests, which confirmed higher thermal stability of the phosphate-based coatings. High char residue formation (~44.5%) and self-extinguishing properties were observed for the phosphate-based coating under non-curing conditions. The superior properties of phosphate-based coatings P5-4h could be ascribed to the collaborative effect of P–Si–N—i.e., the combined activity during the combustion process and pyrolysis of the coated sample. [ABSTRACT FROM AUTHOR]

The controllable α/β ratio of Si 3 N 4 powder was synthesized using tetraethyl orthosilicate (TEOS), glucose, MgCl 2 and YCl 3 ·6H 2 O by sol-gel assisted carbothermal reduction and nitridation (CRN). This study aimed to investigate the impact of various parameters, including a H 2 O/TEOS mol ratio of the sol, a C/Si mol ratio, sintering aids, and the temperature of CRN on the phase transformation of α-Si 3 N 4. The results demonstrated that the H 2 O/TEOS ratio significantly influenced the relative content of α and β phase in Si 3 N 4 by changing the morphological characteristics of SiO 2. When the H 2 O/TEOS ratio was 100, β-Si 3 N 4 powder with an approximate β content over 88 wt% was synthesized at 1500 °C. This remarkable phase transformation was likely facilitated by the eutectic liquid phase consisting of MgSiO 3 /Mg 2 SiO 4. The SEM image revealed rod-like whiskers with a length around 1.4 μm for the β-Si 3 N 4 grains. Due to the presence of liquid phase, the synthesis of spherical-like α-Si 3 N 4 nano-powder with an α-phase content of 91 wt% was achieved at a lower temperature of 1450 °C, with an H 2 O/TEOS ratio of 15 and a C/Si ratio of 4. The size of the particles was about 70 nm due to the reduced reaction temperature. Furthermore, without the addition of any sintering aids or Si 3 N 4 seeds, high purity α-Si 3 N 4 with an α phase content approaching 96 wt% could be synthesized at 1500 °C, using an H 2 O/TEOS ratio of 15 and a C/Si ratio of 4. The resulting α-Si 3 N 4 powder exhibited an extremely regular hexagonal prism shape with a length of approximately 2 μm. [Display omitted] [ABSTRACT FROM AUTHOR]

Our research attempted to investigate the impact of calcination on the synthesis procedure, thickness dependency, and catalytic phases of carbon nanotubes (CNTs) exhibiting a foam-like design. The sol-gel technique of combustion was used to generate three different stoichiometric molar proportions of extremely active Fe:Mo:MgO catalyst significantly powder (namely 1:0.5:13, 1:1:13, and 1:1:50). The crystalline phases of the catalysts were modified by calcination under Air, inert (Ar) and reduced (H 2) atmospheres. XRD, scanning electron microscopy (SEM), in addition to Energy Dispersive X-ray (EDX) analysis were utilized to examine the development of the catalytic compounds' morphological phases, size of particles, shape, and composition of elements.The crystalline shapes, sizes and other morphological characteristics of the highly active catalysts were studied by TEM. Additionally, the BET surface area as well as the average particle diameter, volume of pore, and radius of pore were ascertained using the N 2 sorption isotherm evaluation. Then, the combination of uncalcined and calcined catalysts were employed to generate CNT foams through CVD approach. The CNT foam development findings were examined using a variety of physicochemical strategies. From these studies, we established the relation between the catalytic phases and the growth of MWCNTs with foam-like morphology. Finally, the change of the growth mechanism and diameter of the MWCNT foams over the active catalysts based on the stoichiometric molar ratios between the catalyst and support was analyzed through TEM studies. [ABSTRACT FROM AUTHOR]

In this investigation, our primary objective is to explore the structural, morphological, and electrical characteristics of Bi0.75Ba0.25(FeMn)0.5O3 ceramic material synthesized by the sol-gel method. The prepared sample underwent synthesis through the conventional sol-gel technique. Examination through X-ray diffraction (XRD) unveiled a well-defined rhombohedral structure within the R 3 ´ C space group. Moreover, to evaluate the purity and nano-grain morphology, we utilized energy dispersive spectroscopy (EDX) and scanning electron microscopy (SEM). Electrical assessments were carried out over a frequency span of 100 Hz to 1 MHz and temperatures ranging from 200 to 340 K. Employing the correlated barrier hopping (CBH) model, we analyzed the AC conductivity of our specimen. The activation energy, determined from both DC conductivity and impedance spectra, demonstrated close correspondence, suggesting that both conductivity and r laxation processes are influenced by similar factors. Notably, the dielectric properties hold significant importance, potentially rendering our sample suitable for electronic applications. Furthermore, we calculated thermodynamic parameters, such as enthalpy (ΔH), entropy change (ΔS), and free energy of activation (ΔF), offering deeper insights into the material's behavior and conductivity mechanisms. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) are garnering significant interest because of their cost-effective production process and promising potential for future prospects. This paper presents an innovative approach to the fabrication of DSSCs. Further, a comparative study of DSSCs has been carried to evaluate the performance of the solar cells. BaSnO3 (BSO)- and TiO2-based DSSCs were fabricated with the incorporation of a ruthenium-based N719 dye [(Bu4N)2(Ru)(dcbpyH)2(NCS)2]. The sol–gel technique, facilitated by a microwave oven, was employed for the synthesis of the solar cell materials. Subsequently, these materials were deposited on a fluorine-doped SnO2 glass substrate via doctor blade method. Comprehensive analysis of the structural, optical, and electrical properties of the powder and FTO/BSO/N719/electrolyte/Pt and FTO/TiO2/N719/electrolyte/Pt cells was conducted using x-ray diffraction, scanning electron microscopy, UV–Vis–NIR spectroscopy, and current–voltage (J–V) characteristics. The BSO DSSC demonstrated higher incident photon-to-current conversion efficiency in the UV–Vis region and better overall performance than the TiO2-based cell with a similar experimental environment. The BSO-based DSSC exhibited maximum conversion efficiency (ƞ) of 2.64%, whereas the TiO2-based DSSC demonstrated maximum conversion efficiency of 2.19%. [ABSTRACT FROM AUTHOR]

For alumina (Al2O3) powder produced by corrosion of aluminum, we investigated the effect of the solvent composition (C2H5OH/H2O of 100:0, 80:20, 60:40, 40:60, 20:80, and 0:100 v/v) on the particle size distribution. The powders were calcined at 1473K and identified as α-Al2O3. The particle size of alumina powder obtained with H2O as the solvent was 0.3-100 µm. As the volume fraction of H2O in the solvent mixture increased, the particle size of the alumina powder also increased. With the increase in the H2O volume fraction, agglomeration of the obtained alumina particles was observed by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

The PNIPAM/PAphe interpenetrating nanogels which were responsive to temperature and pH were synthesized. The chemical structure, morphology, particle size and dispersity, temperature-and pH-response, structural color tunability, photonic crystal self-assembly, and sol-gel transition behavior of the interpenetrating nanogels were studied in detail by infrared spectroscopy, scanning electron microscopy (SEM), dynamic light scattering, and optical fiber spectrometry. According to the infrared spectrum and SEM image, the effective interpenetration and good monodispersity of the two networks were confirmed. The analysis of particle size and polydispersity index (PDI) indicated that, with the increase of PAphe content, the particle size of the interpenetrating nanogels correspondingly increased, but the monodispersity remained good. The temperature-and pH-sensitivity experiments proved the responsiveness of the interpenetrating nanogels, which showed that the particle size was significantly decreased when the temperature was increased or the pH value was decreased. Combined with the optical fiber spectrum, it was further found that the interpenetrating nanogel could achieve controllable structural colors by adjusting the particle size. More importantly, they possessed the ability of transition from sol to gel above Tp (32 °C) by the method of test tube inversion. These characteristics showed their potential applications in highly controllable optical materials and the biomedical field. [ABSTRACT FROM AUTHOR]

Luminescent Li3Ba2Gd3Mo8O32:Tb3+ phosphors were synthesized using the sol–gel method, and extensively characterized through various spectroscopic techniques, including x-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, photoluminescence (PL) excitation, and emission. SEM micrographs revealed the irregular and non-uniform morphology and size of the prepared phosphors. The FT-IR spectra offered insights into the functional groups and bonding within the phosphor. The PL excitation spectra at a 545 nm emission wavelength displayed a slight shift in peak positions with a prominent peak at 283 nm, corresponding to the characteristic 4f8 → 4f75d1 transitions of Tb3+ ions, while under excitation at λexc = 283 nm, PL emission spectra exhibited distinct peaks associated with 5D4 → 7Fj (j = 6, 5, 4, 3) transitions. Notably, the transition 5D4 → 7F5 at 545 nm demonstrated strong and particularly high intensity in the Li3Ba2Gd3Mo8O32:0.09Tb3+ phosphor. Photometric analysis showed the potential of this phosphor to serve as a vivid green light source for various display applications. The Li3Ba2Gd3Mo8O32:Tb3+ phosphor may be used for creating sensors for environmental monitoring. Future research could explore its biocompatibility for biomedical applications and improve its targeting and photostability. [ABSTRACT FROM AUTHOR]

In this work, the monolithic ZrO2-Al2O3 aerogels with hollow sphere structure have been prepared by ambient pressure drying. In the preparation process of Al2O3 hollow spheres, different mole of ZrOCl2⋅8H2O was added. We explored the maximum addition of zirconium via ambient pressure drying. A series of ZrO2-Al2O3 aerogels with hollow sphere structure are successfully synthesized using AlCl3⋅6H2O and ZrOCl2⋅8H2O as aluminum and zirconium precursor, and propylene oxide (PO) as the gel initiator by the sol-gel method. It was found that the gelation time was prolonged with increasing zirconium content. When the zirconium content was more than 10%, the gel can't be obtained. It can only get precipitation. With the zirconium content increase from 0 to 10%, the core-shell structure can be formed, proved by SEM and TEM characterizations. The core-shell structure can be kept well under 1000°C. When the heat treatment temperature was at 1200°C, the diffraction peaks were mainly ZrO2 and Al2O3, showed by XRD. With the content of zirconium increase from 0 to 10%, the specific surface area of XZrO2-Al2O3-aerogel increased from 170 to 582 m²/g. [ABSTRACT FROM AUTHOR]

Barium zirconate (BaZrO3, BZO), which exhibits superior mechanical, thermal, and chemical stability, has been widely used in many applications. In dentistry, BZO is used as a radiopacifier in mineral trioxide aggregates (MTAs) for endodontic filling applications. In the present study, BZO was prepared using the sol–gel process, followed by calcination at 700–1000 °C. The calcined BZO powders were investigated using X-ray diffraction and scanning electron microscopy. Thereafter, MTA-like cements with the addition of calcined BZO powder were evaluated to determine the optimal composition based on radiopacity, diametral tensile strength (DTS), and setting times. The experimental results showed that calcined BZO exhibited a majority BZO phase with minor zirconia crystals. The crystallinity, the percentage, and the average crystalline size of BZO increased with the increasing calcination temperature. The optimal MTA-like cement was obtained by adding 20% of the 700 °C-calcined BZO powder. The initial and final setting times were 25 and 32 min, respectively. They were significantly shorter than those (70 and 56 min, respectively) prepared with commercial BZO powder. It exhibited a radiopacity of 3.60 ± 0.22 mmAl and a DTS of 3.02 ± 0.18 MPa. After 28 days of simulated oral environment storage, the radiopacity and DTS decreased to 3.36 ± 0.53 mmAl and 2.84 ± 0.27 MPa, respectively. This suggests that 700 °C-calcined BZO powder has potential as a novel radiopacifier for MTAs. [ABSTRACT FROM AUTHOR]

The thickness of the photoanode film plays a crucial role in the photoelectrochemical (PEC) water splitting process, significantly impacting the photoconversion efficiency. The optimal thickness of the photoanode enhances the photocurrent density by making a balance between light absorption and electrolyte mass transfer. The main goal of this study was to investigate the effect of thickness on the photoelectrochemical performance of the Al2TiO5-based nanocomposite layer as a photoanode under the sunlight simulator. Al2TiO5/TiO2/Al2O3 nanocomposite was initially synthesized utilizing the citrate sol-gel technique, and after the calcination at 800°C, it was deposited on the fluorine-doped tin oxide coated glass slide (FTO) substrate by the doctor blade method in which, several films of various thicknesses can be prepared from a unique paste, by just changing the adhesive tape layers. The Diffuse Reflectance spectroscopy (DRS) technique was utilized to determine the band gap energy value of all specimens, and the field emission scanning electron microscopy (FE-SEM) method was used to investigate the morphology and to determine the thickness of the deposited films. The X-ray diffraction (XRD) analysis exhibited the presence of the tialite (Al2TiO5) phase besides the anatase, rutile, and corundum phases. The cyclic voltammetry (CV) measurements were utilized to estimate the accessible surface area in specimens. Different photoelectrochemical results were expected to be obtained by the photoanodes with different thicknesses of the Al2TiO5/TiO2/Al2O3 nanocomposite films. Photoelectrochemical (PEC) measurements revealed that the highest photoconversion efficiency was achievable by the tialite-based sample by the thickness of about 5 µm which was about 20% higher than the obtained value by the thinner or even thicker tialite-based nanocomposite samples. [ABSTRACT FROM AUTHOR]

In the study, Tb3+‐doped LiMgPO4 phosphors between.10 and 5 mol% were successfully synthesized by the sol–gel process. The crystal structure of Tb3+‐doped LiMgPO4 was identified by X‐ray diffraction (XRD), scanning electron microscopy (SEM), and X‐ray photoelectron spectroscopy (XPS) analyses. The XRD results for LiMgPO4 ceramics doped with Tb3+ indicated a single‐phase up to 5 mol%, accompanied by lattice shrinkage. An SEM analysis of LiMgPO4 samples showed that increasing Tb3+ concentration reduced grain size but did not cause any significant change in slightly angular and round grains. The emission intensity of phosphor increased from.10 to 5 mol%, and no concentration quenching was observed. The luminescence color of LiMgPO4:Tb3+ phosphor can be tuned from blue to green through cross‐relaxation with the increase in Tb3+ concentration. The photoluminescence emissions of LiMgPO4:Tb3+ on the CIE diagram shifted from blue to green as the Tb3+ concentration increased. The color purity of the 5 mol% Tb3+‐doped phosphor showing the strongest emission was measured at 22.71%, whereas the color‐correlated temperature parameter was found to be 5573 K. The phosphors exhibited bi‐exponential decay profiles, and the observed lifetimes of 5D3 decreased with the increase of Tb3+, where the cross‐relaxation effect increased. The quantum efficiency (ɳQE) of the phosphor was determined using the cross‐relaxation process. For Tb3+ concentrations ranging from.1 to 5 mol%, the ɳQE of the 5D3 state decreased from 62.49% to 28.29%. The research may offer a new perspective and new approaches for tuning luminescence in Tb3+‐doped phosphors. [ABSTRACT FROM AUTHOR]

In this study, we investigated the effect of Ni/SiO2 hollow spheres (HS) particle size on the activity for 4-nitrophenol (4-NP) reduction. The SiO2 HS, which serves as Ni support was synthesised by sol-gel method using polystyrene (PS) particles with various diameters. TEM images show that the diameters of the SiO2 HS were 330, 445, and 490 nm. To prepare the Ni/SiO2 HS, Ni particles were immobilised by the impregnation method. SEM images of the Ni/SiO2 HS with a diameter of 330 nm show uniform spherical particles. The Ni were confirmed the surface of SiO2 HS using the EDX. Meanwhile, small particles with irregular shapes were observed in the Ni/SiO2 HS with diameters of 445 and 490 nm. The reaction for 4-nitrophenol reduction was evaluated using the obtained samples. We found that the sample with a diameter of 330 nm shows high activity. Additionally, we reveal that the SiO2 HS enhances the activity by adsorbing the 4-NP. [ABSTRACT FROM AUTHOR]

The presented work sheds light on the impact of CeO2 content and sintering temperatures on the microstructure and physical characteristics of Soda-Lime-Alumino Silicate Glass Ceramics for possible use in dental applications. Samples of nominal composition 45SiO2-15Al2O3-(20-x)NaO2-(20-x)CaO-2xCeO2, (x = 1–5) were successfully synthesized via the sol–gel technique. Synthesized samples were characterized by Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction scan (XRD), and Scanning electron microscopy (SEM) supplemented with an EDX and calculate roughness parameters in addition to physical properties such as (density, free volume, oxygen packing density, etc.). XRD reveals that 850 °C is the optimal temperature to transform samples to their corresponding glass–ceramic derivative, leading to the rearrangement of Qn Si in the glass network. The rearrangement was explained through FTIR, Raman, and the surface morphology of samples. In addition, the increased density is attributed to the high compactness of the glass ceramic formed resulting from the addition of CeO2, which improves the durability and hardness of the samples. [ABSTRACT FROM AUTHOR]

A CdSiO3:Tb3+ deep trap phosphor was prepared by a sol–gel method. The structural information of the prepared phosphors was characterized by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The optical properties of the Tb3+-doped CdSiO3 nanophosphors were investigated by fluorescence spectrophotometry. The afterglow time was more than 10.3 h in the case of Tb3+ doping. The stress–strain of this elastomer was enhanced after the phosphor was compounded with PDMS, and the energy release in the trap was accelerated under external force after applying stress to it, and this composite elastomer may possess mechanoluminescent properties. [ABSTRACT FROM AUTHOR]

Using ytterbium nitrate pentahydrate (Yb(NO3)3·5H2O), ammonium metavanadate (NH4VO3) and citric acid monohydrate (C6H8O7·H2O) as main raw materials, the YbVO4 was prepared by sol-gel method. The samples were characterized by thermogravimetry differential scanning calorimeter (TG-DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflection spectrometer (DRS) and Fourier infrared spectrometer (FT-IR). The photocatalytic activity of YbVO4 was studied by using 10 mg/L methyl orange as simulated wastewater. The results show that pure YbVO4 can be prepared by calcining at 500 °C to 900 °C. The surface of YbVO4 sample prepared at different temperatures is porous and irregular. The forbidden band width of YbVO4 sample calcined at 700 °C is about 3.04 eV. Under ultraviolet light conditions, the degradation rate of methyl orange was over 95% after illumination for 30 min with YbVO4 sample calcined at 700 °C. YbVO4 show excellent photocatalytic activity for degradation of methyl orange. This indicates that YbVO4 is a new photocatalyst with wide application prospect in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

Silica-based xerogel was prepared by the two-step sol-gel method to investigate its methylene blue removal performance. The characteristics of the prepared adsorbent were determined using X-ray diffraction (XRD), Fourier transforms infrared (FTIR), scanning electron microscopy (SEM), and N2 adsorption/desorption analyses. The MB removal studies were conducted with different operating parameters and optimal conditions were found to be 0.06 g adsorbent dosage, and 20 mg.L-1 initial MB concentration at 45 min. The Langmuir isotherm best represents the MB adsorption equilibrium data and the high maximum adsorption capacity was achieved with 1666.67 mg.g-1. The kinetic mechanism of the study is defined by the pseudo-second-order kinetic model. Additionally, the adsorption of MB on xerogel exhibited fast kinetics, reaching a high removal capacity (96.56%) in a minute. [ABSTRACT FROM AUTHOR]

Nanosized Bi1−xSmxFe1−ySnyO3 powders are successfully synthesized using a simple sol–gel auto‐combustion route. The X‐ray diffraction pattern confirms the formation of a pure‐phase crystalline structure in bismuth ferrite (BFO). The co‐doping of Sm3+ and Sn4+ into the BFO structure indicates structural distortion, and a decrease in average crystallite size. Transmission electron microscopy and field‐emission scanning electron microscopy images show agglomerated particles surface morphology with particle size of around 41 nm for BFO and 22 nm for co‐doped BFO sample. X‐ray photoelectron spectroscopy measurements indicate a reduction in oxygen vacancies due to the co‐doping of Sm–Sn into BFO lattice. The co‐doping effect results in a reduction in the value of optical bandgap and an improvement in multiferroics properties. A significant enhancement in the photocatalytic degradation of rhodamine B dye under visible‐light irradiation is observed for co‐doped samples, and these results are further supported by photoluminescence analysis. [ABSTRACT FROM AUTHOR]

We studied the thermal stability and many-sided properties of Y0.5Sr0.5Cr0.5Mn0.5O3 chromite-manganite that was made using the sol-gel method. We focused on the syngony type, unit cell parameters, and x-ray analysis. To confirm the results of the chromite-manganite indexing, the inverse values of the squares of interplane distances (104/d2) and the consistency of the x-ray and pycnometric densities were found to be very close to each other. It was found that the synthesised chromite-manganite crystallises in orthorhombic syngony and has a perovskite-like structure. Scanning Electron Microscopy (SEM) shows that chromite-manganite is uniformly distributed, and the crystallites are sized between 6 and 20 microns. The analysis of the relationship between heat capacity and temperature using the Thermo Gravimetry Analysis (TGA) technique demonstrates the stability of the internal structure and the presence of polymorphic transformations in the sample under study. [ABSTRACT FROM AUTHOR]

In the present research, nanoparticles based on the alumina-yttria system were synthesized using a sol-gel method. Then, the effect of heat treatment on the phase evolution and crystallite size in this composite system was investigated. The produced composite powder was characterized using X-ray diffraction and scanning electron microscopy. Scherrer equation was used to investigate the effect of temperature on crystallite sizes. The composite powder was cold isostatically pressed and subjected to a pressureless sintering process at different temperatures to evaluate its density changes. The X-ray diffraction results showed that the powder sample was initially amorphous. By increasing the temperature, the components of this composite system reacted and Alpha-Al2O3 and Y3Al5O12 phases are formed. The crystallite size of the Theta-alumina phase grew with increasing temperatures up to 1000 C. At higher temperatures, crystallite size decreased due to the decomposition of theta-alumina. The density of the samples increased by increasing the temperature up to 1600 C so that the samples reached a relative density of about 96%. The densification curve of the composite showed three different stages during sintering. Examining the hardness of the samples showed that the hardness increases with the increase of the sintering temperature, and in the sample sintered at 1600 C for 3 hours, the Vickers hardness reached about 14 GPa. [ABSTRACT FROM AUTHOR]

This study explores the potential utilization of walstromite (BaCa2Si3O9) as a foundational material for creating new bioceramics in the form of scaffolds through 3D printing technology. To achieve this objective, this study investigates the chemical–mineralogical, morphological, and structural characteristics, as well as the biological properties, of walstromite-based bioceramics. The precursor mixture for walstromite synthesis is prepared through the sol–gel method, utilizing pure reagents. The resulting dried gelatinous precipitate is analyzed through complex thermal analysis, leading to the determination of the optimal calcination temperature. Subsequently, the calcined powder is characterized via X-ray diffraction and scanning electron microscopy, indicating the presence of calcium and barium silicates, as well as monocalcium silicate. This powder is then employed in additive 3D printing, resulting in ceramic scaffolds. The specific ceramic properties of the scaffold, such as apparent density, absorption, open porosity, and compressive strength, are assessed and fall within practical use limits. X-ray diffraction analysis confirms the formation of walstromite as a single phase in the ceramic scaffold. In vitro studies involving immersion in simulated body fluid (SBF) for 7 and 14 days, as well as contact with osteoblast-like cells, reveal the scaffold's ability to form a phosphate layer on its surface and its biocompatibility. This study concludes that the walstromite-based ceramic scaffold exhibits promising characteristics for potential applications in bone regeneration and tissue engineering. [ABSTRACT FROM AUTHOR]

We investigate the impact of sintering temperature on changes in phase characteristics and grain size in the La0.7AE0.3MnO3 (AE=Ba/Ca/Sr) materials synthesized by the sol-gel method. The materials were sintered at different sintering temperatures of 700°C, 800°C, 900°C, and 1200°C. The refinement of the X-ray Diffraction (XRD) pattern revealed that the La0.7Ca0.3MnO3 and La0.7Sr0.3MnO3 materials exhibited a single phase across all sintering temperatures. For La0.7Ba0.3MnO3, a single-phase structure was observed only at sintering temperature above 800°C. All materials showed an increase in peak intensity and a shift in peak in the range angle 31°-34° towards higher angles correlated to increased sintering temperature. Sintering temperature plays an important role in controlling the grain size. Images obtained by Scanning Electron Microscope (SEM) showed the morphology of La0.7Sr0.3MnO3 sintered at different temperatures (700°C, 800°C, and 900°C). The morphology results show an increment in the average grain size with range of 41.05-69.27nm because of the grain growth as the sintering temperature. [ABSTRACT FROM AUTHOR]

Akermanite (Ak) has promising prospects as an innovative bio-ceramic for bone regeneration. The most common fabrication methods to produce pure Ak powders are long-lasting synthesis routes followed by calcination at high temperatures. This study focuses on the use of microwave irradiation of a solution to provide initial Ak-based powder product that after subsequent heat treatment changes to pure Ak powder. The novel process named microwave-assisted sol–gel method actually speeds up the initial and final stages of pure Ak powder production when compared to the traditional sol–gel with later heat treatment stage. The viscous solution containing magnesium nitrate hexahydrate, calcium nitrate tetrahydrate, and tetraethyl ortho-silicate was microwave irradiated for three minutes. X-ray diffraction showed that the microwaved products after calcination treatment at 1200 °C for 4 h were mostly made of Ak and a small amount of merwinite. However, by increasing the calcination treatment to 1300 °C, single-phase akermanite powder was achieved. By subjecting same precursor and subsequent heat treatments, the typical sol–gel method did not yield pure Ak powder. Thermal analyses and scanning electron microscopy examinations showed that the Ak crystallization temperature was lower in the case of the microwave irradiated product than in the conventional sol–gel route. The microwave irradiated product after calcination showed a porous structure formed by necking between the powder particles with a mean particle size of 2 µm. The results of the in vitro bioactivity evaluation indicated that synthesized Ak was bioactive through proving the formation of hydroxyapatite (HAp) on the surface of pure Ak disc after 7 days of immersion in simulated body fluid (SBF). The cell adhesion findings showed that MG-63 cells adhered and spread well on the Ak disc, suggesting that Ak discs possess good biocompatibility. The results of the MTT assay demonstrated that the cell proliferation of osteoblast-like MG-63 cells was enhanced with the increase in culture time. Our in vitro bioactivity, cell morphology, and adhesion evaluations and in vitro biocompatibility assessment suggested that Ak powders were bioactive and cytocompatible and have a great potential to be selected as an ideal candidate for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

In this study, carbon-free and completely soluble hydrogen peroxide (H2O2) was utilized in place of conventional surfactants as a pore-forming agent. Citric acid was also used in low concentration for the hydrolysis reaction. A sol-gel method was used to prepare bioactive glass (BG) specimens of H2O2-untreated BG, 1M, 2M, and 3M H2O2-treated BGs. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy (EDS), and nitrogen adsorption/desorption isotherm with the Brunauer–Emmett–Teller (BET) method were used for analyzing the samples' phase, surface morphology, chemical composition, constituent composition, pore size, and specific surface area respectively. In vitro bioactivity, as well as biodegradability tests, was performed on samples by immersing them in simulated body fluid (SBF) solution. According to the results, BG particles treated with 2 M H2O2 exhibited higher specific surface area (SSA), which is 189.55 cc/g, and better in vitro bioactivity and biodegradability. [ABSTRACT FROM AUTHOR]

Methylene blue is widely used in the textile industry and is difficult to degrade naturally because of its heterocyclic aromatic structure. One technique that can be used to degrade methylene blue is through a photocatalytic process using ZnO nanoparticles. This study aims to synthesize ZnO nanoparticles using Lidah mertua extract (Sansevieria trifasciata) as a capping agent by the sol-gel method, and determine the characteristics and stability of ZnO nanoparticles in methylene blue photodegradation. The synthesis of ZnO nanoparticles begins with drying Lidah mertua, grinding it, and then extracting it using distilled water. Furthermore, the extract was reacted with Zn(CH3COO)2.2H2O 0.15 M at pH 8. The extract was characterized using Fourier Transform Infrared (FTIR), and the ZnO nanoparticles were characterized using X-Ray Diffraction (XRD), ultraviolet-visible (UV-Vis) DRS, and Scanning Electron Microscopy (SEM). Lidah mertua extract has OH (hydroxyl), CN, CH, and C=C functional groups. The obtained ZnO nanoparticles have a crystal size of 19.324 nm. The crystalline phase is hexagonal; the morphology is spherical, with a particle size of 79.153 nm and a band gap energy of 3.21 eV. ZnO nanoparticles exhibited a methylene blue decolorization of 98.50% through 43.41% by adsorption and 55.09% by photocatalytic mechanism. ZnO nanoparticles showed good stability for a three-cycle reaction. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to evaluate the ability of the bioactive glass-bonds to inhibit the demineralization surrounding the orthodontic brackets and evaluate the physical and mechanical properties in order to be accepted as an orthodontic bonding agent. Materials and Methods: Preparation of mesoporous bioactive glass (MBG) used an improved sol-gel method. The samples were prepared with different surfactant to oil ratio with 12 groups and one control group with six samples each. The debonding characteristics were analyzed using an Instron Universal Testing Machine (UTM). After six months of pH cycling in vitro saliva solution to simulate the oral environment, the microstructure was analyzed using a field emission gun-based scanning electron microscope (SEM). The sample, which is viable in terms of physical and mechanical properties, is converted into a single paste form by addition of resins and compared with the control group Transbond XT adhesive. Results: SEM analysis showed that the prepared MBG particles possess spherical morphology. Novel orthodontic bonding material (BG) provides adequate mechanical properties with bond strength of 7.2 MPa (p =.304) in order to be accepted as an orthodontic bonding agent since its bond strength both at the time of bonding (p = 1) and after six months (p =.325) in simulated salivary conditions is in par with conventional bonding resin (TBXT) with reduced demineralization potential. Conclusion: This novel adhesive results in reduced demineralization surrounding orthodontic brackets and possesses optimal physical and mechanical properties to be accepted as an orthodontic adhesive. [ABSTRACT FROM AUTHOR]

A series of CaY2Al4SiO12:xEu3+ (x = 0.01, 0.03, 0.05, 0.07 and 0.09) phosphors were synthesized by the sol–gel method. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS) techniques were used in the study of the crystal structure, surface morphology, and elemental composition of the prepared phosphors. Photoluminescence (PL) and thermoluminescence (TL) properties were also studied. When the CaY2Al4SiO12:Eu3+ phosphor was excited at 394 nm wavelength, the optimum emission peak centered at 592 nm was found. The calculated CIE coordinates from the PL emission spectra lie in the orange-red region of the visible spectrum. To determine the optimum doping concentration of Eu3+ , the variation in the luminescence intensity with different concentrations of Eu3+ in the CaY2Al4SiO12 host lattice was also studied. To study the TL of the prepared samples, a 60Co- γ (gamma) source was used for irradiation and to determine the trapping parameters such as activation energy (E), order of kinetics (b) and frequency factor (s) of the samples, Chen's peak shape method was used. [ABSTRACT FROM AUTHOR]

A series of Bi1–xLaxFeO3 samples with 0.00 ≤ x ≤ 0.30 was synthesized by the sol–gel method. The effects of lanthanum concentration on the phase formation, microstructure and cycloidal spin ordering were studied using X‐ray diffraction, scanning electron microscopy and Mössbauer spectroscopy. The crystal structure of the La‐doped bismuth ferrite transformed from rhombohedral R3c (x ≤ 0.05) to a mixture of R3c and cubic Pm3m (0.07 ≤ x ≤ 0.15) and finally to a mixture of R3c, Pm3m and orthorhombic Pbam (0.20 ≤ x ≤ 0.30). The Pbam phase, with characteristic porous microstructure shown by microscopy images, was observed in Bi1–xLaxFeO3 compounds for the first time. Based on the Mössbauer spectroscopy, it was found that the cycloidal spin ordering started to disappear at x = 0.07. With increasing La concentration the share of the cycloid decreased from 100% at 0.00 ≤ x ≤ 0.05 to 0% at x = 0.30. At the beginning, for x ≤ 0.02, the anharmonicity parameter, m, of the cycloidal spin ordering was about 0.5, which is typical of a pure BiFeO3 compound. In the range 0.05 ≤ x ≤ 0.25, the m parameter was of the order of 0.1, which indicated the practically harmonic character of the cycloid. The structural transition at x = 0.07 was accompanied by a substantial increase in magnetization. [ABSTRACT FROM AUTHOR]

A series of Bi1–xLaxFeO3 samples with 0.00 ≤ x ≤ 0.30 was synthesized by the sol–gel method. The effects of lanthanum concentration on the phase formation, microstructure and cycloidal spin ordering were studied using X‐ray diffraction, scanning electron microscopy and Mössbauer spectroscopy. The crystal structure of the La‐doped bismuth ferrite transformed from rhombohedral R3c (x ≤ 0.05) to a mixture of R3c and cubic Pm3m (0.07 ≤ x ≤ 0.15) and finally to a mixture of R3c, Pm3m and orthorhombic Pbam (0.20 ≤ x ≤ 0.30). The Pbam phase, with characteristic porous microstructure shown by microscopy images, was observed in Bi1–xLaxFeO3 compounds for the first time. Based on the Mössbauer spectroscopy, it was found that the cycloidal spin ordering started to disappear at x = 0.07. With increasing La concentration the share of the cycloid decreased from 100% at 0.00 ≤ x ≤ 0.05 to 0% at x = 0.30. At the beginning, for x ≤ 0.02, the anharmonicity parameter, m, of the cycloidal spin ordering was about 0.5, which is typical of a pure BiFeO3 compound. In the range 0.05 ≤ x ≤ 0.25, the m parameter was of the order of 0.1, which indicated the practically harmonic character of the cycloid. The structural transition at x = 0.07 was accompanied by a substantial increase in magnetization. [ABSTRACT FROM AUTHOR]

Magnesium oxide (MgO) was synthesized by three different methods: the sol–gel (SG), microwave-assisted sol–gel (MW), and hydrothermal (HT) methods for comparing the influence of the preparation conditions on the properties of the products. The powders were annealed at 450 °C. The samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM/HRTEM), selected area electron diffraction (SAED), energy-dispersive X-ray spectroscopy (EDX), BET specific surface area and porosity, photoluminescence, and UV–Vis spectroscopy. The samples consisted mainly of periclase as a crystalline phase, and the MW and HT preparation methods generated particles with higher specific surface areas. The powders had less-defined morphologies and high levels of aggregation. The optical band gaps of the samples were determined from UV DRS, and the photocatalytic activities of the magnesium oxides obtained by the three methods towards the degradation of methyl orange (MO) under UV light irradiation was evaluated. [ABSTRACT FROM AUTHOR]

The unique structure and physical properties of perovskite-type catalysts make them highly promising for catalyzing efficient coal combustion. Mesoporous perovskite LaNixFe1−xO3 (x = 0.2, 0.4, 0.6, 0.8) coal combustion catalysts were synthesized using the sol–gel method. The effects of the doping amount of B-site doped nickel on both the crystal structure and catalytic performance were investigated. X-ray diffraction, scanning electron microscopy, and nitrogen adsorption–desorption tests were used to characterize the catalyst samples. Thermogravimetric analysis (TG) and activation energy (Ea) calculations were used to assess the catalyst's activity for the catalytic combustion of anthracite coal (JF coal, originating from Shanxi, China). Results revealed that nickel doping created lattice distortion and Ni-Fe alloy interactions. The difference in nickel doping significantly affects the morphology and catalytic activity of perovskite. The addition of LaNi0.6Fe0.4O3 (NI6) with a mass fraction of 5% resulted in the highest average burning rate value (va = 4.52%/min) of JF coal among all synthesized catalysts. The Ea of JF coal catalytic combustion, calculated using the Coats–Redfern method and the Doyle method, showed a good agreement with the TG curves. The LaNixFe1-xO3 series catalysts were found to significantly decrease the Ea of JF coal combustion, with a maximum reduction of 42% compared to the case without any catalyst added. Among the synthesized catalysts, NI6 exhibited a favorable catalytic combustion performance and is thus a promising candidate for the clean and efficient utilization of coal resources. [ABSTRACT FROM AUTHOR]

In the current work, ytterbium oxide (Yb2O3) powders with the europium (Eu3+) were synthesized by the epoxide-driven sol–gel process. Yb2O3-europium xerogels were synthesized at different molar ratios (0, 2, 5, 8, 10, 20, 30, 40, and 50 mol%) and heat-treated at 1273 K in order to yield a dense crystalline material. The powders were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescent studies were performed to establish the relationship between their structural and luminescent properties. After a 1273 K heat treatment, the resultant powders consisted of spherical particles and presented different phases with well-defined reflections characteristic of a cubic-type crystalline structure, with crystallite sizes ranging from 14 to 30 nm. Finally, according to the luminescence studies, emission bands between 550 and 700 nm, due to the 5D0 → 7F2 transition level of the europium ion, were searched using wavelengths of 612 and 364 nm for excitation and emission, respectively. [ABSTRACT FROM AUTHOR]

We present Al2O3-ZnAl2O4-ZnO nanostructure, which could be a prominent candidate for optoelectronics, mechanical and sensing applications. While ZnO and ZnAl2O4 composites are mostly synthesized by sol-gel technique, we propose a solid-vapor growth mechanism. To produce Al2O3-ZnAl2O4-ZnO nanostructure, we conduct ZnO:C powder heating resulting in ZnO nanowires (NWs) growth on sapphire substrate and ZnAl2O4 spinel layer at the interface. The nanostructure was examined with Scanning Electron Microscopy (SEM) method. Focused Ion Beam (FIB) technique enabled us to prepare a lamella for Transmission Electron Microscopy (TEM) imaging. TEM examination revealed high crystallographic quality of both spinel and NW structure. Epitaxial relationships of Al2O3-ZnAl2O4 and ZnAl2O4-ZnO are given. [ABSTRACT FROM AUTHOR]

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Magnetic carbon xerogels were synthesized via direct sonication to load magnetite nanoparticles in sol–gel polycondensation onto resorcinol-formaldehyde gels. The resulting organic gels were carbonized and subjected to surface modification using H2O2 and characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The desorption capacity was optimized using response surface methodology, with the adsorbent dose identified as the most significant quantitative factor. The kinetic adsorption was well described using the Elovich and Power equations. The regeneration capacity was evaluated over four sequential adsorption–desorption cycles, demonstrating the possibility of reusing the adsorbent and reducing the environmental impact. [ABSTRACT FROM AUTHOR]

Photoluminescence-based nanomaterial sensors doped with rare-earth elements have a potential for use in sensitive, portable, and low-cost detectors. The oxide with the formula ZY2ZO5 has potential for fluorescence applications because of its orthorhombic structure, stable physical and chemical properties, and high thermal stability. In this study, BaY2ZnO5 phosphors with various concentrations of Tm3+ and urea ions were synthesized at 1200 °C for 8 h in air by the sol-gel method. The characteristics of the phosphor powders were analyzed by field-emission scanning electron microscopy, X-ray diffraction (XRD), and photoluminescence spectroscopy. The diffraction peaks of phosphors with Tm3+ ion doping concentrations from 0 to 5 mol% and urea additions from 1 to 50 wt% are attributed to the orthorhombic BaY2ZnO5 structure examined by XRD analysis. When the Tm3+ ion concentration is 2 mol%, the maximum emission intensity of the ¹D2→³F4 transition can be obtained, which then decreases with increasing Tm3+ ion concentration. Concentration quenching occurs when the Tm3+ ion concentration is above 2 mol%. For BaY2ZnO5 phosphors prepared by doping with Tm3+ ions and adding urea, excitation with an emission wavelength of 457 nm yields the color tone in the vivid blue region. [ABSTRACT FROM AUTHOR]

This article presents the sol-gel method for depositing La2O3 thin films on n-type Si substrates and quartz substrates, and investigates the impact of annealing temperature on the microcomposition, surface morphology, optical properties, and band characteristics of the films. X-ray diffraction (XRD) analysis indicates that the films are amorphous below 500 °C, with annealing resulting in a hexagonal-phase La2O3 (h-a2O3) and new non-hydrated impurities. Fourier-transform infrared (FTIR) analysis reveals that the prepared La2O3 film is unaffected by moisture. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) provide evidence that the La2O3 film has a smooth, uniform surface without cracks. The roughness increases from 0.426 nm to 1.200 nm, and the film thins from 54.85 nm to 49.80 nm as the annealing temperature rises. The film's transmittance is above 75%, as measured by UV-Vis, and the calculated optical bandgap increases from 5.11 eV to 5.75 eV. The calculated band offset of the La2O3 film is greater than 1 eV, which meets the minimum requirements for MOS devices, thus providing promising prospects for La2O3 films in MOS applications. [ABSTRACT FROM AUTHOR]

Surfaces with translucent and wear-resistant effects have a wide range of applications, especially as protective layers. In this work, a simple and convenient method for the preparation of porous magnesium fluoride (MgF2) coatings was proposed. Nano-porous MgF2 powder was prepared with sol–gel and phase separation methods by optimizing the polymer amount and used for the preparation of thick layers onto PVC substrates. The automated surface area and porosity analyzer (BET) and scanning electron microscopy (SEM) confirmed that the layers containing 0.028‰ PEO presented a 3D structure with pore sizes in the range of 16 nm. The layer reached 93% transmittance in the visible region, a Vickers hardness value of 2889.1 kg/mm2, and a friction coefficient of 0.2 in the wear test. [ABSTRACT FROM AUTHOR]

Ferrites have been widely studied for their use in the biomedical area, mostly due to their magnetic properties, which gives them the potential to be used in diagnostics, drug delivery, and in treatment with magnetic hyperthermia, for example. In this work, KFeO2 particles were synthesized with a proteic sol-gel method using powdered coconut water as a precursor; this method is based on the principles of green chemistry. To improve its properties, the base powder obtained was subjected to multiple heat treatments at temperatures between 350 and 1300 °C. The samples obtained underwent structural, morphological, biocompatibility, and magnetic characterization. The results show that upon raising the heat treatment temperature, not only is the wanted phase detected, but also the secondary phases. To overcome these secondary phases, several different heat treatments were carried out. Using scanning electron microscopy, grains in the micrometric range were observed. Saturation magnetizations between 15.5 and 24.1 emu/g were observed for the samples containing KFeO2 with an applied field of 50 kOe at 300 K. From cellular compatibility (cytotoxicity) assays, for concentrations up to 5 mg/mL, only the samples treated at 350 °C were cytotoxic. However, the samples containing KFeO2, while being biocompatible, had low specific absorption rates (1.55–5.76 W/g). [ABSTRACT FROM AUTHOR]

BaZnCuO3 (BZC) was synthesized using the sol–gel method. The BZC was incorporated in reduced graphene oxide (rGO) to produce BZC/rGO composite. The synthesized catalysts were characterized using Raman, scanning electron microscopy (SEM), powder X‐ray diffraction (XRD), and ultraviolet–visible (UV–Vis) analysis. The comparative effect of BZC and BZC/rGO composite was studied on the thermal decomposition of 3‐nitro‐3H‐1,2,4‐triazol‐5‐one (NTO) and ammonium perchlorate (AP) using the simultaneous thermogravimetric technique (TG‐DTA). Thermal investigations suggest that BZC was a better catalyst for decreasing the thermal decomposition temperature and the thermokinetic parameters of both AP and NTO compared to BZC/rGO composite. BZC can reduce the thermal decomposition temperature of AP and NTO by 121 and 46°C, respectively. The findings support BZC as a possible catalyst in the thermolysis of both NTO and AP. [ABSTRACT FROM AUTHOR]

Doping of potassium in CaCr2O4 as Ca1−xKxCr2O4 with x = 0.2, 0.4, 0.6, and 0.8, using sol-gel technique, to see the structural changes in a regular and periodic variation of K-ions. XRD pattern shows a reduction in peak intensities of CaCr2O4 after potassium doping, principally owing to bonding with Alkali metal in heat treatment of Ca1−xKxCr2O4. It revealed that active species might be confined in the non-crystalline phase, thus impeding their reactivity. XRD of grown samples show their cell parameters of hexagonal crystal symmetry. Morphology of samples in SEM, exhibited the introduction of potassium into the medium of transition metal oxide effects in the development of channeled or layered assemblies. Constituents of synthesized material [Ca1−xKxCr2O4], presenting vibrational stretching of constituent elements as observed in Raman Spectra. The structure of doped sample is predicted favorable for energy storing devices, as having distortion (amorphous linings) in its crystal structure when compared to un doped one, that evident the novelty of this work. [ABSTRACT FROM AUTHOR]

Using lanthanum nitrate, butyl titanate and citric acid as the main raw materials, lanthanum titanate (La2Ti2O7) was successfully prepared by sol-gel method. The samples were characterized by thermogravimetric differential thermal analysis (TG-DTA), X-ray diffractometry (XRD), scanning electron microscopy (SEM) and Fourier infrared spectroscopy (FT-IR). Using 10 mg/L azo dye methyl orange solution as simulated sewage, the photocatalytic activity of La2Ti2O7 was studied by changing the synthesis temperature and light time under ultraviolet light. The results show that pure La2Ti2O7 samples can be obtained at 600 °C∼900 °C. SEM showed that La2Ti2O7 was dominated by irregular particles, and the average grain size was 4 ∼ 6μm. The La2Ti2O7 samples are consistent with approximation zero order kinetic for the degradation of methyl orange. The photocatalytic results showed that the photocatalytic activity of La2Ti2O7 prepared by calcination at 800 °C and 900 °C for methyl orange solution was significantly better than that of other temperature sections. The photocatalytic activity of La2Ti2O7 calcined at 900 °C was the best, and the degradation rate of methyl orange reached about 95% for degradation 60 min. This indicates that La2Ti2O7 is a novel photocatalyst with wide application prospects in the field of UV photocatalysis. [ABSTRACT FROM AUTHOR]

CuCr2O4 spinel is a candidate coating material for central receivers in concentrating solar power to protect structural alloys against high temperature oxidation and related degradation. Coating performance and microstructure of dip-coated and sintered coatings is dictated by the initial particle size of the CuCr2O4 and sintering temperature, but can be compromised by particle agglomeration. In this study, sub-micron particles were synthesised through the Pechini and modified Pechini sol–gel methods. Phase composition was confirmed via X-ray diffraction. Particle growth during calcination of the nanoparticles at different temperatures (650°C, 750°C, 850°C) and times (between 1 and 24 h) was measured via laser diffraction and scanning electron microscopy. The modified Pechini method displayed evidence of smaller particle sizes and greater agglomeration. The kinetics of particle growth observed are consistent with a diffusion limited inhibited grain growth model. [ABSTRACT FROM AUTHOR]