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In this study, Pb(Zr0.54Ti0.46)O3 films were prepared by the sol-gel method with Sm doping concentrations of 0, 0.5, 1, 1.5, 2, and 3 mol. %. Their surface morphology, density, crystal structure, piezoelectric, dielectric, and ferroelectric properties were characterized. The results indicated that, unlike Sm-doped lead zirconate titanate (PZT) ceramics, all Sm-PZT films exhibit a significant increase in the grain size compared to undoped PZT films. Moreover, Sm doping affected their crystal orientation and significantly enhanced their piezoelectric coefficient d33 and remnant polarization (Pr). Notably, the Sm-PZT film with a doping concentration of 1.5 mol. % exhibited optimal (100) orientation, achieving a high piezoelectric coefficient d33 of 279.87 pm/V, 4.55 times that of the non-doped PZT films. [ABSTRACT FROM AUTHOR]

Despite the high demand for nanostructured composites based on zirconia, existing studies primarily focus on their mechanical and electrical properties. However, due to the fragmentated research efforts, it is challenging to compare results across different studies and establish a comprehensive theory for the introduction of graphene sheets into nano-zirconia. This work aims to address these gaps by investigating the dependencies within the synthesis conditions – structure – physicochemical properties, which are critical for the future development of sintering modes for nanostructured composite powders based on zirconia and oxygen-free graphene. We have developed a method that combines sonochemical and sol-gel techniques to synthesize a series of graphene-zirconia hybrid powders with an oxygen-free graphene content raging from 0.60 to 1.99 wt%. The influence of graphene content on the morphology of zirconia in composite was examined. High-Resolution Transmission Electron Microscopy (HRTEM) was utilized to study the synthesized powders, allowing for visualization of the chemical homogeneity of the composite and the absence of agglomeration for both graphene and zirconia, which is critical for producing chemically homogeneous fine-grained ceramics from the powder. Mechanisms for the formation of a suspension of oxygen-free graphene during ultrasonic exfoliation and the subsequent synthesis of a composite based on nano-zirconia are experimentally substantiated and proposed. [ABSTRACT FROM AUTHOR]

This study investigated the catalytic hydrogenation of ethyl nicotinate using Pd/Al 2 O 3 -SiO 2 foam ceramic catalysts prepared via sol-gel impregnation (SI), sol-gel precipitation (SP), precipitation-impregnation (PI), and co-precipitation (CP). We aimed to evaluate the performance and stability of these catalysts as coatings on foam ceramic surfaces in a high-pressure hydrogen reactor at 403 K and 5 MPa. Various physicochemical characterization methods were employed to correlate catalytic performance with physicochemical properties. Results indicated that sol-gel prepared supports had higher specific surface areas, more acidic sites, and better metal-carrier interactions compared to the precipitation method. SEM analyses revealed flatter and smoother coatings from the sol-gel method, while TEM showed uniform Pd distribution with impregnation. Ultimately, the SI method provided the best catalytic performance with a conversion of 86.77 %. The conversion of the substrate remained above 80 % after five cycles. [ABSTRACT FROM AUTHOR]

In this study, a mixed sol-gel technique using silicate, polyvinyl alcohol (PVA), and polyethyleneimine (PEI) was used to various polymers based on PEI and silica gel. The c-PEI blend co-polymer was synthesized by cross-linking branching PEI in an aqueous solution with PVA. The produced c-PEI particles were highly positively charged and fit inside the range of tens to hundreds of nanometers of silica gel. It has been shown that the prepared c-PEI nanocomposite is a very effective antimicrobial, anti-inflammatory, and antioxidant material. In addition to the appropriate investigation of the anti-inflammatory activity using human red blood cells (HRBCs) stabilization, the developed materials were used to explore antimicrobial activity against yeast (Candida albicans ATCC-10231), Gram-negative bacterial strain (Escherichia coli ATCC-25922), and Aspergillus niger NRRL-3 as a fungus. FTIR, XRD, TEM, TGA, and DSC were among the biological and chemical methods used to characterize the produced c-PEI nanocomposites. The agar diffusion method was used to assess the biological activity of the synthesized compounds, and the results revealed a range in their in vitro-antimicrobial inhibitory activity. Based on the type of pathogenic microbe, the majority of the test substances showed a wide range of activity. The examined substances may be appropriate for the creation of an innovative antibacterial and antifungal medicinal medication. [ABSTRACT FROM AUTHOR]

The catalytic activity of Mg-based spinel oxide nanoparticles (NPs) on the combustion behavior of gasoline and their effects on the atomization behavior were determined by droplet scale combustion experiments. MgFe2O4, MgCo2O4 and MgMnO3 spinel oxide NPs were produced by the sol-gel technique and doped into gasoline. The particles with the highest surface oxygen were MgCo2O4 and MgFe2O4 NPs, while the NPs with the largest surface area were MgCo2O4 NPs (517.8433 m2/g). The size of the flame envelope tends to shrink as the oxygen concentration of the particles rises, but an increase in their surface area tends to shorten ignition delay periods. MgFe2O4 NPs increased the flame temperature by 163°C compared to the pure gasoline. While MgFe2O4 and MgMnO3 NPs increased the extinction time of gasoline, MgCo2O4 NPs decreased the severe time by about 75% with the violent micro-explosions they created. In this study, we focused on the production of spinel oxide agents customized for combustion with improved catalytic activity, high flammability, and different component designs, and the results showed that these particles can reduce the soot formation of conventional hydrocarbons. [ABSTRACT FROM AUTHOR]

The thermoluminescence (TL) properties of LaCa₄O(BO₃)₃ (LACOB) phosphors, both undoped and doped with 0.5 % Eu³⁺, were synthesized using a microwave-assisted sol-gel method and analysed under beta irradiation doses ranging from 0.1 Gy to 700 Gy. The TL glow curves revealed prominent peaks at 100 °C and 285 °C for the Eu-doped sample. Activation energy values were calculated using the Hoogenstraaten and Booth-Bohun-Parfianovitch methods, yielding 1.52 eV and 1.48 eV for the undoped sample, and 2.07 eV and 2.01 eV for the Eu-doped sample, respectively. Eu³⁺ ions introduced deeper traps and enhanced the thermal stability of the material. Anomalous increases in TL intensity with rising heating rates were observed, deviating from typical thermal quenching behaviour; this phenomenon was explained using a semi-localized transition (SLT) model. The TL reusability measurements demonstrated a standard deviation of less than 5 %, indicating consistent and reliable performance across multiple cycles. The TL glow curve deconvolution identified six distinct peaks in the undoped sample, while the Eu-doped sample showed a more complex trap structure with eight peaks, indicating the introduction of additional or modified trapping sites by Eu doping. The figure of merit (FOM) values obtained from the deconvolution analysis were all below 2.5 %, indicating a good fit between the observed and fitted TL signals. These findings suggest that Eu³⁺-doped LACOB is a robust material for radiation dosimetry, with its enhanced sensitivity, stability, and versatility across various dosimetric applications. [ABSTRACT FROM AUTHOR]

Ti doping SiTiOC ceramics were prepared by sol-gel method with tetrabutyl titanate (TBT) as modifier. The thermal stability of SiTiOC ceramics with various Ti contents was studied. Meanwhile, the influence of Ti addition on the pyrolysis behavior of SiTiOC xerogel and the structure evolution of SiTiOC ceramics were investigated. The ceramic yield of SiTiOC xerogels were improved greatly by introducing TBT, while the improvement of ceramic yield had an upper limit, for the simultaneous increase of volatile CH 3 O(CH 2) 3 OH. At 900 °C pyrolysis, SiTiOC ceramics were amorphous, and Ti existed by oxides. At 1200 °C and 1400 °C pyrolysis, the crystallinity of SiTiOC ceramics increased, TiC phase appeared in ceramics due to the carbothermal reduction of titanium oxides. With increased Ti contents, TiC contents increased in ceramics attributed to the preferentially carbothermal reduction of titanium oxides. The addition of Ti improved the thermal stability of SiOC ceramic system, but such an improvement was sensitive to the Ti contents. 0.05Ti-1400 ceramic exhibited the highest thermal stability with the mass change of 6.51 %. Because the oxide scale of 0.05Ti-1400 ceramic was complete and dense, with lowest thermal stress and oxygen diffusion rate for the least TiO 2 formed in the oxide scale. Concurrently, the TiO 2 particles formed with long rod-like which distributed uniformly in oxide scale that can toughen the oxide scale. While for 0.1Ti-1400 and 0.2Ti-1400 ceramics, the increase of Ti outward diffusion degree damaged the oxide scale and accelerated the oxidation of free carbon. [ABSTRACT FROM AUTHOR]

Nanocrystalline Li 0.5 Al x Fe 2.5- x O 4 (x = 0.0 to 0.8 in steps, x = 0.2) compounds were prepared using the sol-gel auto-combustion technique. X-ray diffraction (XRD) analysis confirmed the single-phase cubic spinel structure, which showed that the lattice constant changed significantly, especially in the x = 0.6 sample, where it decreased clearly. The crystallite size decreased with increasing Aluminium content, reaching a small value of about 5 nm for the composition x = 0.8 sample. Raman peaks of pure LiFe 2 O 4 were determined in both phases (alpha and beta), while smaller peaks at 198 and 236 cm−1 that related to the alpha phase were distinguished. All peaks diminished in intensity after Al3+ ions were doped to LiFe 2 O 4 except for the peak at 700, where it became predominantly. The bandgap of the samples was deduced and analyzed from Tauc's plot according to UV–Vis spectra. The change in the electronic structure of the Li-Al ferrites, at which the size of the ferrite becomes close to the de Broglie wavelength, results in a band gap for the Al replaced by LiFe 2 O 4 with different electronic configurations. The variation of the fundamental part of the dielectric constant (ε ′), loss tangent (tan δ), and AC conductivity with frequency has been discussed with composition. The increase in Al3+ ion content affected the coercive force, as it decreased, while the saturation magnetism increased when adding Aluminium (x = 0.2) and then began to decline gradually. [ABSTRACT FROM AUTHOR]

Silica glasses co-doped with varying concentrations of Er3+ (0.8, 1.5, 4, and 8 mol %) were fabricated employing the sol-gel technique. The effects of erbium concentration were evaluated through several characterization techniques, including X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), UV–visible transmission spectroscopy, and photoluminescence analysis. The incorporation of erbium ions significantly altered the structural, optical, and photoluminescence properties of the doped glasses. XRD analysis revealed the presence of SiO 2 in both tetragonal and hexagonal forms, along with Er 2 SiO 5 crystalline phases. SEM images showed irregular rod-shaped structures with agglomeration and micro-flake cubic shapes. FTIR spectroscopy provided insights into the structural characteristics of the materials. Notably, the optical band gap energy of the glassy films increased, accompanied by fluctuating Urbach energy and a slight reduction in the refractive index, attributed to structural changes within the glass network. Photoluminescence spectra indicated strong emissions at 523 and 543 nm, corresponding to the transitions 2H 11/2 → 4I 15/2 and 4S 3/2 → 4I 15/2 , respectively. Additionally, a notable near-infrared emission at 1532 nm was observed, linked to the transition 4I 13/2 → 4I 15/2. The color coordinates of the produced glasses were found to be near the green or yellow regions, suggesting potential applications in optical amplifiers, lasers, and low-emissivity coatings. [ABSTRACT FROM AUTHOR]

Amorphous alumina films are isotropic and have no grain boundaries, which make them have smooth surfaces, excellent properties, and wide applications in protective coatings, catalysis, and microelectronics. However, high-quality alumina films were usually prepared by vapor-phase approaches which need expensive equipment and long production time. Additionally, amorphous films are long-range disordered, which makes the study of structure–property relationships challenging. Here, a simple sol–gel method is employed to obtain high-quality amorphous Al2O3 thin films. The microstructure, morphology, and mechanical properties of amorphous Al2O3 thin films were systematically investigated. All the Al2O3 thin films heat-treated at 600–800∘C are in amorphous state with ultrasmooth surface (Ra values about 0.29–0.43 nm) and high mechanical properties (elastic modulus ∼170 GPa, hardness ∼20 GPa). The mechanical properties (E and H) of Al2O3 films gradually increase with the increase of heat-treating temperature. Additionally, the Al coordination of the amorphous alumina films are analyzed by solid-state NMR and correlated with the mechanical properties. The results show that in amorphous alumina, the presence of tetrahedral Al ([4]Al) and octahedral Al ([6]Al) is helpful to improve the mechanical properties, while the five-coordinated Al ([5]Al) is not conducive to improve the mechanical properties. The results demonstrate that sol–gel method is an attractive alternative to time-consuming and expensive vapor-phase approaches and are useful for scale-up to applications and research of amorphous alumina films. [ABSTRACT FROM AUTHOR]

In this study, the photocatalytic degradation of methylene blue (MB) dye was explored by applying biochar/Ag nanocatalyst.Biochar (activated carbon) was produced from the Astragalus shrub by a slow pyrolysis procedure. Preparation of biochar/Ag nanoparticles was performed using the sol-gel technique, and the physical properties of the prepared nanocatalyst were studied using BET, FTIR, XRD, FESEM, and EDX analyses. According to the analyses, Ag was successfully placed on the biochar particles.Investigations on the Ag/activated carbon (AC) ratio, initial concentration dye, lamp power, pH, catalyst dosage, and amount of H2O2 were conducted to acquire the highest removal efficiency of MB. The maximum degradation rate of MB dye was attained under optimal conditions, including initial dye concentration of 5 mg/L, pH 9, 20 mL of H2O2, 60 mg of AC/Ag nanoparticle dosage, and 100 min under 80 W lamp power. The highest MB dye degradation in the mentioned circumstances was achieved at 96.09%.The kinetic survey likewise represented that the elimination of MB dye using AC/Ag nanocatalysts follows the first-order model, and the optimum time for the photocatalytic removal procedure of methylene blue through biochar/Ag nanocatalysts is 100 min. The stability of the AC/Ag nanoparticles during five rounds was favourable, and only 5.79% of MB dye degradation yield was diminished. [ABSTRACT FROM AUTHOR]

Restricted biodegradability, toxicity, and carcinogenicity of basic fuchsin dye are the principal reasons that motivate scientists to find methods to remove it. Photocatalytic degradation technology is simple, environmentally friendly, inexpensive, efficient, and does not yield secondary pollution. Most of the catalysts used to degrade basic fuchsin dye require expensive chemicals to prepare. Therefore, the novelty in our work comes from the utilisation of low-cost chemicals for the facile synthesis of Mn0.5Zn0.5Fe2O4/Fe2O3 nanocomposite using the pechini sol-gel method. The synthesised samples at 300, 600, and 900°C were encoded as F300, F600, and F900, respectively. The XRD confirmed that the average crystallite size of the F300, F600, and F900 samples is 95.08, 122.32, and 160.21 nm, respectively. Hence, as the calcination temperature increases, the crystallite size increases as a result of coagulation that occurs at higher temperatures. The FE-SEM images showed that the F300, F600, and F900 samples consist of spherical, (polyhedral and spherical), and (hexagonal and spherical) shapes with an average diameter of 258.64, 470.12, and 625.32 nm, respectively. This change in morphology at different temperatures is due to the discrepancy in the rate of liberation of organic matter at different temperatures. In the presence of hydrogen peroxide, 0.05 g of the Mn0.5Zn0.5Fe2O4/Fe2O3 nanocomposite degrade 100% of 25 mL of 25 mg/L of basic fuchsin dye at pH = 8 within 25 min. Consequently, the other side of the novelty of our work is the ability of the synthesised nanocomposite to effectively degrade a high concentration of the basic fuchsin dye in a short time. [ABSTRACT FROM AUTHOR]

The present study investigates the influence of the substitution of CaO by SrO on the structure, degradation and in vitro apatite formation of sol–gel-derived bioactive glasses with composition of 58SiO 2 – (38- x)CaO – x SrO – 4P 2 O 5 , where x varies between 0 and 10 mol.%. The IV-type nitrogen adsorption/desorption isotherms and pore size values (ranging from 5.41 to 12.56 nm) confirmed the mesoporous structure of the synthesized glasses. The detailed structural analysis was carried out by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). As network modifiers, the addition of Ca and Sr oxides disrupted the bonds of bridging oxygens (BOs) and resulted in the formation of non-bridging oxygens (NBOs), where the substitution of Ca with Sr led to an increase in Q 1 units and a decrease in Q 3 units. The effects of the addition of Sr on sample degradation and apatite formation were assessed using an assay in tris-(hydroxymethyl)-aminomethane and hydrochloric acid (Tris–HCl) and simulated body fluid (SBF). The results demonstrated that the substitution of CaO by SrO in the CaO – SiO 2 – P 2 O 5 bioglass system altered the glass structure, resulting in reduced sample degradation and delayed apatite formation. This suggests that the incorporation of Sr into bioactive glasses may serve as a promising strategy to regulate the structure, dissolution behavior and apatite formation of silicate-based glasses, particularly concerning their long-term applications within the human body. [ABSTRACT FROM AUTHOR]

Improving the performance of LaMnO 3 perovskite is essential to make it an efficient and ultra-light electromagnetic wave (EMW) absorbing material. In this work, LaMn 1-x Fe x O 3 powders (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) were synthesized by controlling the doping of Fe3+ ions at the B-site using the citric acid-assisted sol-gel method. The effects of Fe3+ ions doping content on crystal structures, magnetic properties and EMW absorption performances were investigated. The obtained LMFO-4 sample exhibited a minimal reflection loss of −54.99 dB at 13.68 GHz, with an adequate absorption bandwidth (RL < −10 dB) spanning 4.56 GHz (11.6–16.16 GHz) at a matching layer thickness of 2.0 mm. The exceptional EMW absorption performances could be attributed to the Jahn-Teller effect, the double-exchange interactions and the magnetic interactions of Mn and Fe ions. Furthermore, the Computer Simulation Technology (CST) simulations demonstrated that the Radar Cross Section (RCS) value of LMFO-4 was lower than −25.10 dBm2 across angles ranging from −90° to 90° with a thickness of 2.0 mm, indicating the remarkable radar wave attenuation ability. These insights provided valuable guidance for advancing perovskite-based materials tailored for efficient and ultra-light electromagnetic wave absorption applications. [Display omitted] • LaMn 1-x Fe x O 3 perovskites (0 ≤ x ≤ 0.5) are synthesized using the citric acid assisted sol-gel method. • The effects of Fe3+ ions doping content on crystal structures and EMW absorption performances are investigated. • The RL of LMFO-4 is −54.99 dB at 13.68 GHz and the EAB is 4.56 GHz (11.6～16.16 GHz) at a matched thickness of 2 mm. • The monostatic RCS across angles ranging from −90° to 90° are simulated using CST Studio Suite. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising energy source, requiring increasingly efficient photocatalysts for production under UV–Vis light. For the first time, this study evaluated the photocatalytic generation of H 2 using the Er3+:Y 3 Al 5 O 12 /Pt/ZnO material. The effect of the Er3+:Y 3 Al 5 O 12 garnet on the photocatalytic activity of Pt/ZnO under UV–Vis light was evaluated. Firstly, both the ZnO and the Er3+:Y 3 Al 5 O 12 garnet were synthesized by a sol-gel method, and the Pt-coating of the ZnO was performed using a sonochemical method. The samples were characterized through XRD, SEM-EDX, Raman, UV–Vis-DRS, N 2 adsorption-desorption, XPS, and fluorescence spectroscopy. The H 2 production under UV–Vis light was measured using mass spectrometry, and the effect of methanol as a sacrificial agent was evaluated. The synthesis method allowed obtaining ZnO with a defined spherical morphology and high crystallinity, with the H 2 generation of 676 μmolh−1g−1. In the meantime, the Pt-coating reduced oxygen vacancies and the recombination rate of e−/h+ pairs, and the garnet addition in a mass ratio of Pt/ZnO:garnet at 1.0:0.3 led to the highest H 2 production (1304 μmolh−1g−1), with only a 20 % decrease after 5 production cycles. Finally, adding 10 % v/v methanol significantly enhanced the H 2 generation (3026 μmolh−1g−1). Altogether, the Er3+:Y 3 Al 5 O 12 /Pt/ZnO material with the sacrificial agent (10 % v/v methanol) improved H 2 production from ZnO by a factor of 4.5. Thus, this study demonstrates that the Er3+:Y 3 Al 5 O 12 garnet is an efficient alternative for significantly increasing H 2 production from Pt/ZnO. [ABSTRACT FROM AUTHOR]

A transparent device in perovskite HEO La(Mn 0.2 Cr 0.2 Fe 0.2 Co 0.2 Ni 0.2)O 3 modified Cu 2 Y 2 O 5 /CdIn 2 O 4 is prepared via a simple approach of sol-gel method. The Cu 2 Y 2 O 5 /La(Mn 0.2 Cr 0.2 Fe 0.2 Co 0.2 Ni 0.2)O 3 /CdIn 2 O 4 exhibits high transparency of ∼85–90 %, obvious photovoltaic conversion efficiency enhancement of ∼2.5 × 103-folds (PCE of ∼1.12 %), and stable output in 5-months. This is mainly attributed to the La(Mn 0.2 Cr 0.2 Fe 0.2 Co 0.2 Ni 0.2)O 3 modification, as well as the appropriate Fermi level and high quantum yield. In this system, the La(Mn 0.2 Cr 0.2 Fe 0.2 Co 0.2 Ni 0.2)O 3 solid solution, with extra carrier injecting/driving from synergism of mixed transition metals charge compensation and lattice distortion, can improve the carrier kinetic equilibrium for PCE-transparency balance. Additionally, it can increase p-type conductivity through the synergism of Cu vacancy/interstitial oxygen. Moreover, the inorganic perovskite HEO La(Mn 0.2 Cr 0.2 Fe 0.2 Co 0.2 Ni 0.2)O 3 with modification stability is beneficial for the actual applications. [ABSTRACT FROM AUTHOR]

This study focused on pristine Fe 2 O 3 , pristine Co 3 O 4 , and Fe 2 O 3 -Co 3 O 4 composite using the Pechini sol-gel method for ethanol gas sensing applications. Advanced characterization techniques were used to analyze the phase, morphology, and composition of the synthesized materials. Gas sensors were then fabricated and used for ethanol gas sensing at different temperatures. The results indicated that Fe 2 O 3 -Co 3 O 4 composite gas sensor crystallized at 600 °C, had higher response compared to both pristine Fe 2 O 3 and pristine Co 3 O 4 gas sensors. The composite sensor manifested a high response of 26.2–100 ppm ethanol at 250 °C, while maximum responses of pristine Co 3 O 4 gas sensor was only 4.4 at 200 °C and that of pristine Fe 2 O 3 sensor was 11.4 at 300 °C. The boosted sensing performance of the composite sensor was related to the formation of p-n heterojunctions between Co 3 O 4 and Fe 2 O 3 in composite sensor, the formation of dangling bonds at interfaces, and high intrinsic ethanol sensing properties of Fe 2 O 3. [ABSTRACT FROM AUTHOR]

Multi-component solid solution carbide is a promising material due to its excellent mechanical strength, thermal stability, and resistance to chemical corrosion. In this study, we intentionally designed and synthesized three types of solid solution carbide powders using the sol-gel method: (Ti 1/3 Zr 1/3 Ta 1/3)C, (Ti 1/3 Zr 1/3 Hf 1/3)C and (Ti 1/4 Zr 1/4 Ta 1/4 Hf 1/4)C. The results show that the liquid-phase precursor undergoes pyrolysis at 800 °C and subsequently form homogeneous single face-centered cubic structure solid solutions upon thermal treatment at temperatures exceeding 1800 °C. The obtained powders exhibited ultra-fine and uniform particle sizes of 340 nm, 248 nm, and 401 nm, respectively. Furthermore, the oxidation behavior of the three types of carbide powders in air shows that Hf and Ta elements are of great significance in improving oxidation resistance. The solid solution of Hf increases the initial oxidation temperature, while Ta tends to form a complex oxide with Zr, which helps to improve the oxidation temperature resistance. This work therefore contributes to filling the gap of employing the sol-gel method in the fabrication of multi-component solid solution carbide materials and provides novel insights into their synthesis mechanism and oxidation behaviors. [ABSTRACT FROM AUTHOR]

The strength and toughness of aerogel composites can be enhanced by incorporating alumina ceramic paper as a reinforcing material. However, the production processes often suffer from issues related to poor evenness and low porosity. Herein, alumina ceramic paper with high evenness and porosity was prepared using foam forming technology and utilized as a reinforcing material for alumina-SiO 2 aerogel composites. Initially, the hydroxyl groups (Al-OH) of the alumina ceramic fibers were adsorbed onto the hydrophilic moieties of bubbles via hydrogen bonding during the foam forming, which hindered the migration of the fibers and facilitated their dispersion. Subsequently, the alumina ceramic paper was fabricated through the optimization of the squeezing dehydration and defoaming processes. Finally, the alumina-SiO 2 aerogel composites were formed via the sol-gel method. The alumina ceramic paper exhibited excellent multifunctional properties, including high porosity and evenness, which significantly enhanced the mechanical and thermal insulation properties of the alumina-SiO 2 aerogel composites. In conclusion, highly porous alumina ceramic paper presents significant potential for application in various fields, including automotive, construction, and aerospace. [ABSTRACT FROM AUTHOR]

The system 58SiO 2 -34CaO-2MgO-xZnO-(6-x)P 2 O 5 , (where x = 0, 1, 2, 3, 4 mol%) prepared by using Sol-Gel method. Samples examined by using as X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Energy dispersive X-ray spectroscopy (EDX) studies. In order to evaluate the in vitro bioactivity samples were immerged in simulated body fluid (SBF) for durations of 7, 14 and 28 days. All bioceramic were found bioactive. Results indicating that the initial presence of magnesium (Mg) and zinc (Zn) hindered the synthesis of HAp. However, it did not restrict the bioactivity. Samples were also assessed for friendly environment for human cell growth, antioxidant behaviour of sample to reduce the oxidative stress on surrounding tissues and samples are also provide the protection against gram positive and gram negative microorganisms. While Mg and Zn may hinder the synthesis of highly crystalline HAP, they can simultaneously improve the biological properties of HAP-based biomaterials, making them more suitable for certain medical applications. [ABSTRACT FROM AUTHOR]

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]

Lead-free Bi 0.5 Na 0.5 TiO 3 -SrTiO 3 (BNT-ST) thin films with various thicknesses were deposited on the Pt(111)/Ti/SiO 2 /Si(100) substrates employing a sol-gel technique with a two-step annealing process. Despite the variations in thickness, the films exhibited a consistent polycrystalline structure, evidenced by identical diffraction peaks, albeit with differences in intensity. An imprint became evident in micro-thick films, increasing with film thickness. Also, the emergence of self-polarization was observed in thicker films detected by piezoresponse force microscopy. Noteworthy is the pronounced influence of film thickness on strain response, with the 1.38 μm-thick films demonstrating a large strain of 1.18%. The outstanding strain response can be attributed to the notable contribution of electric field-induced phase transition and polarization dynamics. This work provides a promising potential application of micrometer-thick BNT-ST thin films in advanced actuator devices. [ABSTRACT FROM AUTHOR]

The research and modification of semiconductors through different synthesis routes allow obtaining materials with optimal properties to induce new energy levels and improve charge separation efficiency. In this context, the sol‐gel method was used to synthesize TiO2‐based materials doped with different percentages of MnOx to evaluate their photocatalytic activity in the degradation of the herbicide 2,4‐dichlorophenoxyacetic acid (2,4‐D) in water under UV irradiation. Characterization results revealed a reduction in crystallite size to 7.2 nm. Adding MnOx enhanced the optical absorption of TiO2, resulting in a shift toward the red end of the spectrum of the forbidden energy band. The photocatalytic activity increased significantly with the percentage of MnOx, reaching a maximum degradation of 70 % in 6 hours with the 3 MnTi material. This increase was attributed to the synthesis method, which facilitated the formation of nanostructured heterojunctions mainly composed of TiO2 and MnO2, reducing the recombination of electron‐hole pairs. TEM analysis confirmed these structures. A reaction mechanism for the 3 MnTi material is proposed, considering the mobility of charge carriers and the photooxidation processes of the pollutant. [ABSTRACT FROM AUTHOR]

Bismuth-based semiconductor materials have garnered significant attention because of their appropriate optical bandgap and substantial photoelectric conversion efficiency. Enhancing the photocurrent and fill factor of photovoltaic films is essential for developing high-performance optoelectronic devices. In this study, high-performance BiVO 4 -ZnTiO 3 multilayer films were fabricated using a straightforward sol-gel method, where the incorporation of ZnTiO 3 films significantly improved the photovoltaic performance of BiVO 4. Through structural design aimed at enhancing light utilization, the BiVO 4 -ZnTiO 3 multilayer film achieved a photocurrent density of 1.9 mA/cm2 at 450 nm, along with a fill factor of 46.8 % in the composite multilayer structure. The improvement in film performance is attributed to the overall multilayer stacking effect. This study offers a novel approach for utilizing bismuth-based semiconductors in optoelectronics. [ABSTRACT FROM AUTHOR]

Degradation of bisphenol A (BPA) or 4, 4'-isopropylidene diphenol, a common endocrine disruptor was carried out by ultrasound irradiation at 40 kHz in the presence of ZnO nanoparticles, NaCl, Na2SO4, H2O2, and CCl4. The BPA degradation is carried out at pH 6.3(stock solution), pH 2, and 8 in the presence and absence of the aforesaid additives at different concentrations. The degradation behavior of BPA was measured through the UVvisible spectrophotometer. The ZnO nanoparticle was synthesized by the Sol-Gel method and characterized by SEM, EDX, and XRD. The experimental result shows that the rate of degradation increased with the addition of additives. The synthesized ZnO nanoparticle drastically favored the degradation rate of BPA. The BPA degradation rate is also improved in acidic conditions compared to the basic conditions. Therefore, the BPA can be efficiently removed from the aqueous medium using ultrasound irradiation in the presence of ZnO nanoparticles, NaCl, Na2SO4, H2O2, and CCl4. [ABSTRACT FROM AUTHOR]

A universal technique is described for producing nanostructured indium, gallium, and zinc oxides by the sol-gel method from respective metal nitrates with ethylene glycol as a complexing agent. The powder X-ray diffraction analysis of the samples obtained evidences that they do not contain noticeable concentrations of impurities, and their unit cell parameters are typical of these compounds. The microstructures of the samples are studied by electron microscopy. The band gap is determined based on diffuse reflectance of the samples using the Kubelka–Munk method, and it is shown that its boundaries correspond to the available literature data. [ABSTRACT FROM AUTHOR]

Tetraphenylethene (TPE) is known as a molecule that exhibits aggregation-induced emission (AIE). In this study, pendant hydroxyl groups were introduced onto polyfluorene with a TPE moiety. Sol-gel reactions of polydiethoxysiloxane (PDEOS) were carried out in the presence of hydroxyl-functionalized AIE polyfluorene (TPE-PF-OH) and polydimethylsiloxane carrying pendant hydroxyl groups (PDMS-OH) to immobilize AIE polyfluorene into a PDMS/SiO2 hybrid in an isolated dispersion state. The luminescence intensity from this three-component hybrid increased with the increase in silica content. The luminescence intensity decreased with increasing external temperature. For the control experiment, sol-gel reactions of PDEOS were carried out in the presence of hydroxyl group-free polyfluorene (TPE-PF) and PDMS to obtain ternary composites. We found that the luminescence from this composite was not significantly affected by the silica content or external temperature. We synthesized temperature-responsive AIE materials without changing the concentration or aggregation state of the AIE molecules. [ABSTRACT FROM AUTHOR]

In this study, Bi 0.9 Er 0.1 FeO 3 /In 2 O 3 composites were prepared by sol-gel method. The structure, morphology, elemental valence and ethanol gas sensing performance were characterized and studied. At 330 °C, Bi 0.9 Er 0.1 FeO 3 /In 2 O 3 composite sensor exhibits a response of 112 when exposed to 100 ppm ethanol, roughly 7 times higher than Bi 0.9 Er 0.1 FeO 3. The response/recovery time of the sensor is 5 s/75 s, alongside good selectivity, anti-interference and stability. The improved performance in gas sensing may be ascribed to heterojunctions between Bi 0.9 Er 0.1 FeO 3 nanoparticles and In 2 O 3 nanoparticles. Meanwhile, Bi 0.9 Er 0.1 FeO 3 /In 2 O 3 composites have larger specific surface area, which increases adsorption sites and supports reactions more effectively. [ABSTRACT FROM AUTHOR]

The main objective of the present work is to get insight into the polarization switching and dielectric response of PVDF-TrFE with incorporation of BaTiO3 (BTO) nanoparticles. For this purpose, cost-effective solvent casting technique was used, to prepare PVDF-TrFE/BaTiO3 composite free-standing films. It is necessary to prepare films in which BTO nanoparticles are distributed homogenously without agglomeration. Surface functionalization technique is reported to be useful in homogenous distribution of the nanofiller in polymer matrix. However, addition of surface modifier causes reduction in the permittivity of the polymer nanocomposite and deteriorates the desired properties. Therefore, the main aim of the present work is to obtain homogenous free-standing PVDF-TrFE/BaTiO3 composite films in which filler is dispersed without any use of surface modifier. Hence ferroelectric particles are dispersed in the ferroelectric polymer matrix. It has been observed that nanocomposite is much more complex compared to the simple models based on spheres dispersed in a medium. Complexities arise due to the strain and interfacial effects of the BTO nanoparticles on the ferroelectric matrix which exhibits marked effect on structural and electrical response of the system. Consequently, specific concentration of filler has been identified at which optimum ferroelectric and dielectric properties of PVDF-TrFE/BaTiO3 composite have been achieved. Incorporation of more than a desired concentration of filler affects the chain alignment and causes reduction in the β-phase content. Correlation between structural and electrical response has been discussed in detail to explain the non-monotonic trend of polarization as a function of BTO content. [ABSTRACT FROM AUTHOR]

The development of photocatalysts that can efficiently remove organic pollutants is crucial for environmental clean-up. In this study, we present the synthesis of stable TiO2-SnO2 nanocomposites using the sol-gel method. Various characterization techniques were employed to analyze the structural, morphological, and optical properties of the samples. The photocatalytic efficiency of the nanocomposites was assessed by examining the degradation of Congo red (CR) dye under sunlight. All samples exhibited over 90% degradation within 2 h, with the optimized sample achieving 99.0% efficiency and a rate constant of 3.3 × 10− 2 min− 1. The stability of the photocatalyst was validated through reusability tests, which showed more than 90% efficiency even after five cycles. The photocatalytic mechanism is thoroughly explained using band edge positions and effective charge transfer processes due to the formation of a heterojunction. Additionally, BET analysis and zeta potential measurements were conducted to gain a deeper understanding of the catalytic process. [ABSTRACT FROM AUTHOR]

Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study demonstrates the improvement of core loss through the reduction of eddy current loss in soft magnetic composites (SMCs) composed of TiO2-coated Fe powder and epoxy resin. A thin and uniform TiO2 insulating layer was successfully deposited on the surface of Fe powder via a sol-gel process, employing titanium (IV) butoxide (TBOT) as the precursor. Scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy analyses confirmed the formation of a core/shell Fe/TiO2 structure, with a coating thickness of several tens of nanometers. Increasing the TBOT concentration and coating duration time led to an improved quality factor (Q factor) and a shift of the maximum Q factor values to higher frequency regions. Notably, the permeability was decreased slightly from 14.2 to 13.4, but the core loss, measured at various AC frequencies under 20 mT and then separated into hysteresis loss and eddy current loss at 1 MHz, was significantly reduced from 573 to 435 kW/m3 when the Fe powder was coated with TiO2 using a 2.5 wt.% TBOT solution for 8 h. This reduction in core loss is attributed to the effective suppression of inter-particle eddy currents by the TiO2 insulation layer. [ABSTRACT FROM AUTHOR]

The cubic phase of Magnesium oxide (MgO) nanoparticles is synthesized by the sol-gel method. The nanoparticles were subjected to annealing at 500∘C to enable stress and strain analysis. Characterization of the annealed nanoparticles was performed using powder X-ray diffraction (XRD). Through analysis of the XRD peak profile, key properties, such as crystallite size, lattice strain, deformation stress, and deformation energy density, were determined. These parameters were estimated using three models such as the Williamson–Hall-Isotropic Strain Model (W-H-ISM), the Williamson–Hall-Anisotropic Strain Model (W-H-ASM), and the Williamson–Hall-Energy Density Model (W-H-EDM). The estimations were based on the W-H plot derived from the powder XRD data. The findings of this study contribute to a better understanding of the structural and mechanical characteristics of annealed MgO nanoparticles, thus informing their potential applications. [ABSTRACT FROM AUTHOR]

Flexible ceramic nanofibers are used widely in thermal insulation, new energy, filter, and biomedicine. The growth mechanism and phase transformation of ZrO2 are related to the flexibility of nanofibers. The lack of flexible property has limited the high-end applications of ZrO2 nanofibrous membranes. In this work, flexible ZrO2 nanofibers were processed via sol-gel electrospinning and calcination in air at different temperatures. The as-fabricated ZrO2 nanofibers can maintain the excellently flexible property in temperatures ranging from room temperature to 700 °C. These favorable characteristics make the ZrO2 nanofibers a promising choice for new energy, filter, and other thermal insulation fields. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize TiO2 and silver-containing TiO2 layers on Ti6Al4V titanium alloy substrates, also known as titanium grade 5 (TiGr5), to provide corrosion resistance and antibacterial activity. The TiO2 layers were prepared through the sol-gel method and dip-coating technique. Silver introduction into the layers was performed in two different ways. One was the impregnation method by dipping the TiO2 layer-covered metal in aqueous AgNO3 solutions of various concentrations (TiO2/AgNO3), and the other was by direct introduction of AgNO3 into the precursor sol (Ag-TiO2). The two methods for incorporating AgNO3 into the coating matrix are novel, as they preserve silver in its ionic form rather than reducing it to metallic silver. The samples were put through electrochemical characterization, namely potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), and were tested in Hank's solution, simulating a physiological environment. The behavior of the layers was monitored over time. Also, the thin layers' thickness and adhesion to the substrate were determined. Microbiological evaluation of the Ag-doped coatings on glass substrates confirmed their significant bactericidal activity against Gram-negative Escherichia coli. Among the two types of coatings, the impregnated coatings demonstrated the most promising electrochemical performance, as evidenced by both EIS and potentiodynamic polarization analyses. [ABSTRACT FROM AUTHOR]

In this study, ZrB 2 -SiC-ZrC (ZSZ) composite powders with molar ratios C/(B + Zr + Si) = 1.5, 1.9 and 2.4 were obtained by sol-gel method and boro/carbothermal reduction reaction. Meanwhile, the impact of heat treatment temperature (1100 °C–1600 °C) and holding time (1 h–2.5 h) on the resulting powders were studied. The results showed that the ZSZ powder precursors were first completely converted to ZrO 2 , SiO 2 , B 2 O 3 and pyrolytic carbon after heat treatment at 1200 °C under the optimized molar ratio (2.4) and holding time (2.5 h). Then, the transformed oxidation products and pyrolytic carbon were completely transformed into ZSZ composite powders after optimized heat treatment at 1500 °C. The synthesized ZSZ composite powders are characterized by the core-shell structure, in which ZSZ particles act as the inner core are encapsulated by the low-crystalline ZrB 2 phase as the outer shell to form a core shell structure. The ZSZ composite ceramic materials prepared using the core-shell structural powders have excellent ablative properties in the range of 2000 °C, with the mass and line ablation rate of −3.5 × 10−4 g/cm3 and 2.39 × 10−3 mm/s, respectively. [ABSTRACT FROM AUTHOR]

Borate bioactive glasses (BGs) have become indispensable in biomedicine for their exceptional bioactivity and tunable degradation characteristics. This study presents the synthesis and comprehensive evaluation of BGs within the x B 2 O 3 -CaO-Na 2 O-K 2 O-MgO-P 2 O 5 system, featuring varying compositions of B 2 O 3 (x = 40, 55, and 70 mol.%), using both sol-gel and melting techniques. A systematic investigation of their structural evolution, degradation kinetics, apatite-forming capabilities, and cytotoxicity has been conducted. The results demonstrate that the borate BGs with elevated B 2 O 3 content significantly accelerates the degradation rate and enhances bioactivity across both synthesis methods, as B 2 O 3 content increases from 40 to 70 mol%. Notably, the sol-gel derived BG samples demonstrate pronounced degradation, with mass loss reaching up to 90 %, and superior hydroxyapatite formation in simulated body fluid, surpassing the performance of their melting-derived counterparts. Cytotoxicity assays with MC3T3-E1 cells reveal no significant inhibitory effects from any of the borate bioglasses. Moreover, ab initio molecular dynamics simulations have been utilized to elucidate the relationship between structural alterations and in vitro bioactivity, with a particular emphasis on the boron coordination number. These findings provide a promising strategy for the development of borate BGs with tailored degradation profiles and excellent bioactivity, making them as strong candidates for various biomedical applications. [ABSTRACT FROM AUTHOR]

Calcium phosphate cement (CPC), composed of silica-modified hydroxyapatite (HA-SiO 2), cerium oxide (CeO 2), and silica (SiO 2), was developed as an osteoporosis bone filler. The effect of CeO 2 and SiO 2 content on the CPC's properties, such as crystal parameters, surface properties, antibacterial activity, and toxicity properties, were studied. HA-SiO 2 was prepared using the sol-gel method, while CeO 2 was prepared using the precipitation method. HA in HA-SiO 2 has crystal properties similar to pure HA. Synthesized CeO 2 contains Ce3+ and Ce4+ ions with Ce3+/Ce4+ = 0.34. Computational calculation predicted that the CeO 2 (111) surface and glycine molecule interaction was categorized as chemisorption. Moreover, CeO 2 has antibacterial activity toward Escherichia coli and Staphylococcus aureus. Combining HA-SiO 2 and CeO 2 did not change the adsorption-desorption isotherm curve type, but slightly decreased the surface area, total pore volume, and average pore. Increasing the percentage of CeO 2 and adding 10 % SiO 2 (w/w) affected the particle's size and CeO 2 distribution. However, CPC lost antibacterial activity toward Staphylococcus aureus but adding 10 % SiO 2 (w/w) increases the bacterial activity toward Escherichia coli close to that of pure CeO 2. The MTT assay using pre-osteoblast MC3T3E1 cells showed that the CPC has IC 50 = 4227 μg/ml or is nontoxic. [Display omitted] [ABSTRACT FROM AUTHOR]

The prime goal of this novel work is to investigate the efficacy of spinel zinc ferrite as a thermoelectric material and its performance enhancement for high temperature applications. Zn 1-x Ni x Fe 2 O 4 (0 ≤ x ≤ 0.2) were prepared by sol-gel method and their structural, morphological, and thermoelectric behaviours were examined as functions of composition and temperature. Among the studied compositions, Zn 0.8 Ni 0.2 Fe 2 O 4 exhibits the highest electrical conductivity (σ) of 49.83 S/m, the largest power factor of 6.66 μW/mK2, and the lowest thermal conductivity (κ) of 0.36 W/mK at 947 K, thus extending to an overall enhancement in the thermoelectric figure of merit (zT). Conduction through electron hopping is proven to be the main driving force for the enhancement in electrical and thus thermoelectric properties. Results reveal that thermoelectric properties of ZnFe 2 O 4 can potentially be enhanced by the doping Ni at Zn site and opens up an exciting opportunity for the utilization of this spinel ferrite as a novel thermoelectric material for applications involving elevated temperatures. [Display omitted] • Thermoelectric figure of merit of ZnFe 2 O 4 was considerably enhanced by doping Ni. • Electron hopping is found to be one of the major contributors for the enhancement of electrical conductivity. • The dopant is also effective in reducing the thermal conductivity of ZnFe 2 O 4 at higher temperatures. • The results indicate that the studied material is suitable for high temperature (>700K) thermoelectric applications. [ABSTRACT FROM AUTHOR]

This paper presents a study on the microstructure and magnetic properties of LaCoO 3 (LCO) thin films, and also the micropatterning of LCO thin films using a novel photo-sensitive sol-gel lithography method. It is found that higher heat-treatment temperature can promote the healing of cracks and filling of pores, resulting in refining the grains, and improving the density of LCO film. The film treated at 850 °C has a larger nucleation energy, which makes the distribution of nucleation sites more uniform, promoting the healing of cracks and filling of pores, refining the grains, and improving the density of LCO film. LCO precursor sol, metal chelates with UV photosensitivity were synthesized by adding BzAcH photosensitizer. LCO micro-arrays with diameters of 50 μm, as well as other fine patterns with a minimum line width of about 2 μm were successfully prepared by a UV mask lithography technique. In contrast, our novel lithography method eliminates the need for photoresist, as the fine pattern is formed during the preparation of the LCO gel film, which is the advantages of our lithography method over traditional techniques. [ABSTRACT FROM AUTHOR]

The study involved conducting kinetic measurements for the dry reforming of methane (DRM) over a Ni–Rh/Al 2 O 3 (85%)-ZrO 2 (15%) catalyst under a wide range of operating conditions (temperature: 500–900 °C, total flow rate of the inlet feed: 50–100 mL/min). The support material was prepared using the sol-gel method, followed by impregnation of Ni–Rh catalyst on the incipient wetness of the Al 2 O 3 –ZrO 2 support. The calcined, reduced and spent samples were characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), inductively coupled plasma atomic emission spectrometer (ICP-AES), N 2 adsorption/desorption and CHNS analyzer, and tested for activity, yield and stability in DRM reaction. Furthermore, kinetic behavior of Ni–Rh/Al 2 O 3 –ZrO 2 catalyst in DRM process was investigated by assuming DRM and reverse water-gas shift (RWGS) reactions take place on two kinds of different active sites. Experimental data were fitted using rate expressions based on the Langmuir-Freundlich (LF) isotherm for DRM and RWGS reactions. The activation energy for the DRM reaction was optimized at 43.62 kJ/mol, falling within the reported literature range of 24.73–108.9 kJ/mol. Statistical indices indicated that the kinetic model accurately predicted CO 2 conversion compared to other responses, with an error of 12.054%. The computed and experimental trends for CH 4 and CO 2 conversions, H 2 and Co yield in terms of temperature were similar with each other and the difference between the calculated and experimental trends was lower for conversions compared to yields. • Kinetic of DRM process was assessed utilizing a LF approach. • Kinetic model predict well experimental CO 2 conversion than other responses. • The error of the kinetic model was determined to be 12.054%. • DRM reaction activation energy aligning well with existing literature reports. [ABSTRACT FROM AUTHOR]

In the past few decades, the synthesis of cost-stable electrocatalysts for low-overpotential oxygen evolution processes remains problematic for energy conversion technologies. In the present study, the sol-gel process produced a very effective Mo-doped mesoporous CaZrO 3 catalyst. According to the electrochemical data, the Mo-doped CaZrO 3 exhibited a reduced overpotential (ղ) of around 225 mV, resulting in j 10 mA/cm2 (current density) and a reduced Tafel gradient of 35 mV/dec, which leads to the enhanced OER performance. Mo-doped CaZrO 3 had a turnover frequency of 0.75 s−1 and the electrochemically active surface area corresponding to this frequency was 373.75 cm2. BET surface area analysis also validated the doping of Mo with CaZrO 3, which was accomplished by producing a high surface area that further promotes electrolyte penetration and the charge transfer rate. Both cyclic stability and chronoamperometry evaluation of Mo-doped CaZrO 3 demonstrate that it is stable for over 60 h. It has been demonstrated through these findings that the electrocatalytic efficiency of perovskite oxide (CaZrO 3) can be boosted through surface modification with Mo-doping. The purpose of this research is not only to open up a new path for the remarkable oxygen evolution process but it can also be utilized for prospective application in the near future. [Display omitted] • Mo-doped CaZrO 3 was effectively produced via the sol-gel method for OER. • According to the BET study, the surface area of the Mo-doped CaZrO 3 was 74 m2/g. • The Mo-doped CaZrO 3 had an overpotential (225 mV) and a Tafel plot (35 mV/dec). • Mo-doped CaZrO 3 demonstrated effective reliability for 60 h at current density (10 mA/cm2). • OER activity was boosted as a result of homogeneous morphology. [ABSTRACT FROM AUTHOR]

Energy‐efficient, high‐specificity gas sensors provide practical suitability for stability and response factors. The recognition of ignitable gases (methane (CH4), propane (C3H8), and hydrogen (H2) and harmful gases (carbon oxide (CO) and hydrogen sulfide (H2S)) in an enclosed and out‐of‐door space are essential to safeguard the human lives and infrastructural spaces. One of the crucial conductive‐type metal oxide semiconductor (MOS) gas sensors yielding wide applications is zinc oxide (ZnO). This study highlights the various types of ZnO gas sensors, their fabrication techniques, and specific vital characterizations. The devices based on MOS are utilized to sense various target gases through redox reactions. The variation in oxide surface with target gas interactions is transduced to a change of sensor conductance. This review also provides insight into integrating ZnO gas sensors with technologies such as materials engineering, the Internet of things and big data. Moreover, this review addresses ZnO gas sensors’ challenges and future directions. [ABSTRACT FROM AUTHOR]