One-step Sol Research Articles

Preparation of zirconium hydrogen phosphate coatings on alkali thermal titanium via a one-step sol–gel method to improve the friction resistance, bioactivity, and osteogenic potential

Titanium implants are widely used in dental restorations for patients suffering from dentition defects. However, the biologically inert of Ti, poor osteoinduction properties and the release of Ti particles due to friction between the bone and the implants can inhibit osseointegration and adversely affect the success rate of implantation. In this study, a zirconium phosphate (ZrP) coating was constructed on the surface of alkali thermal titanium (AT-Ti) via a one-step sol–gel approach. Subsequently, the friction resistance, bioactivity, and osteogenesis properties of the prepared coating were studied. The surface characterization results confirmed that AT-Ti was successfully coated with amorphous ZrP, and ZrP modification was found to effectively reduce the friction rate. In addition, the surface morphology after friction test was smoother. In terms of the bioactivity, the presence of a phosphate group in the ZrP coating led to the effective enrichment of Ca2+ to promote the formation of hydroxyapatite (HAp). It was also discovered that ZrP exhibited an excellent performance in cell viability and mineralization experiments, in addition to up-regulating the expression of osteogenesis related genes. Overall, ZrP modification of AT-Ti leads to an excellent friction resistance, bioactivity, and osteoinductive properties, thereby indicating its broad application prospects in implant therapy.

New insights into the resistance of silica aerogel to temperature up to 1200 °C

Silica aerogel (SA) with high specific surface area (903 m2/g) and pore volume (6.81 cm3/g) was synthesized via base-catalyzed one-step sol–gel process. Thermal stability of SA under high temperature was estimated from structure evolution with temperature and time. The results demonstrate that the SA is thermally stabile at 1000 °C within 120 min (leaving specific surface area of 286 m2/g and pore volume of 1.46 cm3/g) and 1200 °C within 30 min (leaving specific surface area of 129 m2/g and pore volume of 0.59 cm3/g). The research provides new insights into the resistance of silica aerogels to high temperature, which is significant for application under harsh conditions.

Preparation of hexagonal boron nitride polymer systems with one-step sol–gel synthesis for pH-controlled drug delivery

Preparation of hexagonal boron nitride polymer systems with one-step sol–gel synthesis for pH-controlled drug delivery

Interfacial effect on the microwave absorption properties in Y3Fe5O12/Fe2O3

In this work, the interfacial effect on the electromagnetic wave (EMW) absorbing performance in Y3Fe5O12 and Fe2O3 material system synthesized by one-step sol–gel method followed by various sintering temperature was studied. The synthesized samples were first characterized by performing x-ray diffraction (XRD), scanning electron microscope (SEM) and vibrating sample magnetometer (VSM) measurements. A linear dependence of the saturation magnetization with the YIG content in the samples was observed that the saturation magnetization increases from 4.18 to 20.2 emu/g when the YIG crystal content is increased from 43 % to 88 %. Then, the EMW absorbing performance were studied by measuring dielectric parameters of the samples in the X-band. The experimental results indicate that the higher sintering temperature reduce the intensity of Fe2O3 peaks and enhance the formation of YIG chemical structure. Due to the both Fe2O3 and YIG crystal phases, the Fe2O3/Y3Fe5O12 interface enhances the EMW polarization and thus EMW absorbing performance. The minimum reflection loss was determined as −15.4 dB at 9.5 GHz frequency in YF1000 sample. The experimental results demonstrate that the sintering temperature has the prominent effect on the structural, magnetic and EMW absorbing properties of YIG. The results would be useful for the YIG-based microwave device applications.

Rare earth-doped Ni/MgAl2O4 catalysts prepared via a one-step sol–gel method for steam reforming of volatile organic solvents at low temperatures

To develop efficient steam reforming catalysts that are widely applicable to various volatile organic solvents under low temperatures, rare earth (La, Ce or Pr)-doped Ni/MgAl2O4 were prepared via a novel one-step sol–gel method. Through various characterizations and DFT calculations, it demonstrated that the rare earths not only improved the catalyst structure, but also promoted the dispersion, electron density and d-band center of Ni. Consequently, all the rare earth-doped Ni/MgAl2O4 catalysts exhibited higher catalytic activity in steam reforming of different volatile organic solvents than the Ni/MgAl2O4 in 500–550 °C. Thereinto, the 10Ni-2La/MgAl2O4 performed the best, achieving a conversion efficiency of 97.3% at 550 °C for the mixture of toluene, acetone, tetrahydrofuran, and n-hexane. The outstanding performance of Ni-La/MgAl2O4 catalyst arises from the structural compatibility between low-spin La atom and Ni cluster, which enables La to modify Ni dispersion and electronic structure more significantly than Ce or Pr.

Siloxane-type single-ion conductors enable composite solid polymer electrolyte membranes with fast Li+ transporting networks for dendrite-proof lithium-metal batteries

Solid polymer electrolytes (SPEs) significantly improve the operational safety of lithium-metal batteries (LMBs) by replacing the flammable liquid electrolytes, but still suffer from key limitations including low ionic conductivities, inferior lithium-ion transference numbers (tLi+), and poor mechanical properties. Herein, a novel poly (ethylene oxide) (PEO)-based composite electrolyte, with a semi-interpenetrating polymer network, is fabricated via in-situ cross-linking siloxane-type single-ion conductors (SICs) in PEO SPEs by one-step sol–gel method, enabling they simultaneously achieve the enhanced electrochemical and physicochemical properties. Incorporating a thermodynamically compatible SIC network not only reduces the crystallization of PEO matrix while facilitating the segmental relaxation of polymer chains, but also contributes to dissociating Li-salt and forming a three-dimensional conducting network for fast Li-ion transport. Thus, the resulting composite SPEs exhibit higher ionic conductivities (1.10 × 10−5 S cm−1 at 25 °C and 1.41 × 10−4 S cm−1 at 60 °C), tLi+ (0.52), and electrochemical window stability (4. 59 V) than pure PEO SPEs. Furthermore, this stable SIC networks can also enhance the mechanical performance and thermal stability of the composite SPEs. Thanks to these merits, the composite SPEs show the significant feasibility to regulate Li deposition and suppress the growth of Li dendrites, affording excellent stability and compatibility with Li metal. As a result, the Li/Li symmetrical cells using the composite SPEs show excellent cycling performances without an evident polarization enlargement for more than 900 h. The LiFePO4/Li batteries also achieve a remarkable capacity of 132.8 mA g−1 at 1C and exhibit impressive cycling abilities with 91.9% retention over 250 cycles. This study provides a promising concept for developing advanced composite SPEs for potential application in solid-state dendrite-free LMBs.

Al3+ doped CuFe2O4 efficiently activates peroxymonosulfate for long-term and stable degradation of tetracycline: Synergistic and regulatory role of Al3+

The water pollution caused by the proliferation of tetracycline hydrochloride (TC) has seriously harmed human beings and the environment. Therefore, it is necessary to design a catalyst that can effectively remove TC and immobilize it for practical applications. Spinel catalysts can effectively resolve the problem of TC contamination in water. In this research, in order to solve the problems of poor dispersion, inferior performance and weak stability of copper ferrate (CuFe2O4). Al3+-doped CuFe2O4 was prepared by the one-step sol–gel-combustion method and used as a peroxymonosulfate (PMS) activator to promote the degradation of tetracycline (TC). A series of degradation experiments and characterization indicated that Al3+-doped CuFe2O4 could remove more than 95 % of TC within 20 min, its first-order kinetic degradation constant was 2.5 times higher than that of CuFe2O4. The mechanism by which Al3+ could improve the degradation of CuFe2O4 may be as follows: the presence of Al3+ increased the electron transfer rate of the metal; effectively increased the specific surface area of the catalyst, provided more active sites; the Al-O-Fe and Al-O-Cu bonds generated by Al3+ immobilized the highly reactive metal ions, reducing ion leaching and improving the stability of the catalyst. Electron paramagnetic resonance and quenching experiments identified the synergistic effect of both radicals and non-radicals in the reaction. Electrochemistry and X-ray photoelectron spectroscopy (XPS) further verified the possible catalytic mechanism. Furthermore, by further immobilization, the 1 g of catalyst could continuously degrade 9 L of TC in water without stirring, showing excellent practical applications. This work provides a reference for improving the catalytic performance of ferrite spinel materials and solving the difficult problem of catalyst recovery in the real environment.

Synthesis of superhydrophobic coatings based on silica nanostructure modified with organosilane compounds by sol–gel method for glass surfaces

In the present study, the superhydrophobic coating was synthesized by spherical silica nanostructures modified with organosilane compounds for glass surfaces. To optimize the conditions in terms of cost-effectiveness and create a super-hydrophobic coating with a high contact angle, the response surface method of the central composite design (CCD) model was performed for the StÖber method, and the contact angle was defined as the response surface for the model. Tetraethoxysilane (TEOS) was used as a precursor and poly(dimethylsiloxane) (PDMS) was used to modify the surface of a spherical silica nanostructure synthesized by a one-step sol–gel method using a base catalyst. The accuracy of the research was checked by the contact angle measurement test and an angle of 162° was obtained. XRD, FT-IR, EDS, SEM, DLS, and AFM analyzes were performed to investigate the synthesis of silica nanostructure. Chemical resistance was performed in acidic, neutral, and alkaline environments and the contact angles were 127°, 134°, and 90°, respectively, which indicates that the coating created on the surface glass has good chemical resistance in acidic and neutral environments.

Role of a novel cationic gemini surfactant (CGS) on a one-step sol-gel process and photocatalytic properties of TiO2 powders.

TiO2 nanoparticles were prepared using a sol-gel process in combination with a novel cationic gemini surfactant (CGS) with amide functional groups at low temperatures. Titanium (IV) isopropoxide (TIP) and CGS were used as the starting materials and as effective agents, respectively, to orient the nanoparticles during the sol-gel synthesis. To reveal both the structural and morphological properties of the nanopowders prepared in this work, they were characterized using X-ray diffraction (XRD) analysis, scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET) surface area apparatus. The pore volume and pore size were calculated using the Barrett-Joyner-Halenda (BJH) model on the desorption branch. The experimental results show that the surface area and average crystallite size of the obtained TiO2 nanopowders vary between 160-203 m2/g and 27-49 nm, respectively. It was observed that the N2 adsorption-desorption isotherms for almost all samples of TiO2-X% CGS (X: mass of CGS) show the typical Type I with a hysteresis loop of H4. The photocatalytic activities of the CGS-modified nanocomposites are evaluated not only by the photocatalytic degradation of methyl orange (MO) but also by the reduction of Cr(VI) as model pollutants in the presence of visible light.

The Calcination Effect on the Crystallinity, Nitrogen Content, and Pore Structure of Nitrogen-Doped Titanium Dioxide

Mesoporous nitrogen-doped titanium dioxide nanomaterials have been synthesized through a one-step sol gel process with dodecylamine as the pore template as well as the nitrogen source. The calcination process plays an important role in the crystallization process, determination of doped nitrogen, and pore formation. The effect of calcination temperature on the material structure was studied by calcination treatment of the as-synthesized material at several temperature variations. The resulting materials were characterized using FTIR, XRD, XPS, and N2 gassorption analysis. The results showed that the anatase TiO2 crystal structure began to form with calcination at 400 °C. The higher calcination temperature tends to cause the transformation of anatase crystal phase into rutile. The higher calcination temperature also affects the doped nitrogen content, where the pore-templating molecules begin to disappear at a calcination temperature and leaving a number of dopants on TiO2. All dopants are released from TiO2 at a calcination temperature of 600 °C. The optimum calcination temperature to form mesoporous structure was 450 °C, and the sintering occurs at a calcination temperature higher than optimum temperature indicated by the collapse of the pore structure.

Features of the surface layer structure of the magnetosensitive materials functionalized by silica with thiourea groups and their applying for selective Cu(II) and Au(III) ions removal

One-step sol–gel synthesis for covering magnetic particles with polysiloxane layers with ≡Si(CH2)3NHC(S)NHC2H5 groups has been proposed. Unique properties of this functional group, containing sulfur and nitrogen, and the developed approach open wide (and novel) opportunities for the controlled surface design. A number of factors affecting the characteristics of such materials and their sorption properties towards heavy metal ions were analyzed. Results of scanning and transmission electron microscopy studies, Fourier-transform infrared spectroscopy, nitrogen adsorption–desorption measurements, elemental analysis, thermogravimetric analysis, and X-ray powder diffraction analysis indicated that, depending on the ratio of core/shell components, the resulting spherical moieties with size of 35.1–43.1 nm, can form agglomerates of larger sizes. Packing of these aggregates offers porosity to such materials, having a dense or loose polysiloxane shell, with thiourea groups load of 0.67–1.05 mmol/g. The synthesized materials proved to be effective in extraction of Cu(II), Pb(II), Cd(II), Hg(II), Ag(I), Au(III), Zn(II) ions from aqueous solutions, as well as in selectively adsorption of Au(III) ions at pH = 3 and Cu(II) ions at pH = 5.5. X-ray photoelectron spectroscopy demonstrated different types of interactions between metal ions and the thiourea groups, depending on pH.

Easy and Low-Cost Method for Synthesis of Carbon–Silica Composite from Vinasse and Study of Ibuprofen Removal

Vinasse was successfully utilized to synthesize carbon–silica composite with a low-cost silica source available in Thailand (sodium silicate, Na2SiO3) and most commonly used source, tetraethyl orthosilicate (TEOS). The composites were prepared by a simple one-step sol–gel process by varying the vinasse (as carbon source) to silica source (Na2SiO3 or TEOS) weight ratio. The resulting composites were characterized by N2 adsorption, moisture and ash contents, pH, pHpzc, bulk density, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX). The composites had highest surface area of 313 and 456 m2/g, with average mesopore diameters of 5.00 and 2.62 nm when using Na2SiO3 and TEOS as the silica sources, respectively. The adsorption of a non-steroidal anti-inflammatory drug, ibuprofen, was investigated. The contact time to reach equilibrium was 60 min for both composites. The adsorption kinetics were fitted by a pseudo-second-order model with the correlation coefficient R2 > 0.997. The adsorption isotherms were well described by the Langmuir model (R2 > 0.992), which indicates monolayer adsorption. The maximal adsorption capacities of the Na2SiO3- and TEOS-based composites were as high as 406 and 418 mg/g at pH 2, respectively. The research results indicate that vinasse and a low-cost silica source (Na2SiO3) show great potential to synthesize adsorbents through a simple method with high efficiency.

Insight into the effect of Nb5+ on the crystal structure and electrochemical performance of the Li-rich cathode materials

The density functional theory (DFT) and electronic structure around the Fermi level results show that the binding energy change of Nb-doped samples is much higher than that of the pristine sample. • Nb-doped Li-rich materials are synthesized via a modified one-step sol–gel and high-temperature calcination method. • Nb-doped Li-rich materials show outstanding electrochemical performance. • The electrochemical performance of Nb-doped Li-rich materials was interpreted by the density of states. The Nb-doped Li-rich materials Li 1.2 (Mn 0.54 Ni 0.13 Co 0.13 ) 1-x Nb x O 2 are synthesized via a modified one-step sol–gel and high-temperature calcination method. The crystal structure and surface morphology of synthesized materials are analyzed through X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. After optimization, the Nb-0.02 sample exhibits exceptional electrochemical performance, that is, the initial discharge-specific capacity of 305.9 mAh g −1 at 0.08 C and 202.6 mAh g −1 at 1 C, respectively. Combined with the result of the density of states (DOS), we found that the doping of Nb 5+ into the crystal structure significantly reduces the value of the band gap of the Li 2 MnO 3 (1.07 eV). At the same time, the strengthened Nb–O bond and Nb 5+ with big ionic radius, regulate the degree of oxygen ion participation in the redox reaction and enhance the electrochemical performance of the Li-rich materials.

Optical, ferroelectric, and magnetic properties of NiTiO3–CoFe2O4 composites prepared by one-step sol–gel method

Optical, ferroelectric, and magnetic properties of NiTiO3–CoFe2O4 composites prepared by one-step sol–gel method

A dual engine-triggered DNA walker based on luminous perylene-TiO2 nanospheres for efficient electrochemiluminescence bioassay

Despite the intrinsic programmability and flexible biological functions of DNA walkers, it remains challenging for traditional DNA walkers to precisely control mechanical running paths in nanoscale spaces. In this work, an elegant dual engine-triggered DNA walker was elaborated based on precise orientation protocol, applying the DNA cube as the scaffold for anchoring the dual swing arms as engines and tracks as signal switches. The order arrangement and dual engines enhanced the operating efficiency and controllability of the DNA walker markedly. Moreover, the electrochemiluminescence (ECL) molecule perylene doped-titanium dioxide (Pe-TiO2) organic–inorganic nanospheres with low cost and high reproducibility were synthesized as the ECL emitters by one-step sol–gel method. It was worth noting that TiO2 gel not only restricted the stacking mode of Pe molecules in vibration and rotation, but also enhanced the interfacial charge transfer ability in organic–inorganic hybrid mode, resulting in the improvement of ECL efficiency and structural stability. Based on the luminous Pe-TiO2 nanospheres, a ternary ECL system was proposed with S2O82− as coreactant, and silver nanoparticles (Ag NPs) as coreaction accelerator. Ultimately, by combing the dual engine-triggered DNA walker with the ternary ECL system, an efficient ECL bioassay platform was developed for microRNA let 7a (let-7a) detection with a wide linear range from 10 fmol/L to 100 nmol/L and a low detection limit of 7.0 fmol/L. Hence, this work offered a universal strategy to predesign walking paths and improve loading capacity in virtue of DNA nanostructures, as well as to expand the biology research of planar organic luminophores in an organic–inorganic hybrid manner.

Zinc oxide and gold textured Janus nanowire integration in an impedimetric sensor for leptospirosis DNA-biomarker recognition.

A "Janus particle" refers to the production of two materials in a single system and shows a difference in physical characteristics, and two surfaces participate in the formation with different chemistries. This research generated the Janus using a hybrid of zinc oxide (ZnO) and gold (Au) on the sensor surface toward making high-performance DNA sensors. The Janus ZnO/Au-textured film was synthesized via the one-step sol-gel method, which involves a suitable ratio of a mixture of ZnO sol seed solution. The synthesized Janus ZnO/Au-textured film undergoes a low-temperature aqueous hydrothermal route to synthesize quasi-one-dimensional nanowires. The average grain size in the Janus ZnO/Au nanotextured wire was 41.60 nm. The fabricated nanotextured wire was further optimized by tuning the thickness and characterized by XRD and high-resolution microscopy. Electrical characterization was conducted on the Janus ZnO/Au nanotextured wire coupled with an interdigitated electrode sensor to detect the specific leptospirosis DNA strand. The generated device is capable of detecting lower DNA concentration at 1 × 10-13 M with a sensitivity of 8.54 MΩ M-1 cm-2 . The high performance is attained on linear concentrations of 10-6 -10-13 M with the determination coefficient, "I = 135437.63C-3609.07" R2 = 0.9551. A potential strategy is proposed as a base for developing different high-performance sensors.

Effect of precursor material, pH, and aging on ZnO nanoparticles synthesized by one-step sol–gel method for photodynamic and photocatalytic applications

Effect of precursor material, pH, and aging on ZnO nanoparticles synthesized by one-step sol–gel method for photodynamic and photocatalytic applications

Selective catalytic reductive removal of NOx with decreased interference from SO2 and H2O by use of Sm-modified SmxCo0.05-xCe0.05Ti0.9Oy catalysts

This work presents a novel and highly efficient NH3-SCR catalyst, Sm-modified CoCeTiOx, synthesized by a simple one-step sol–gel method. The optimum Sm0.03Co0.02Ce0.05Ti0.9Ox catalyst with a high BET surface area shows more than 90% NO conversion and nearly 100 % N2 selectivity at 180–440 °C. We investigated the relationship between Sm content and surface reactivity using NH3-TPD, H2-TPR, XPS, and in-situ DRIFTS. It demonstrated that the Sm-doping could precisely regulate the acidity and redox ability of the SmaCo0.05-aCe0.05Ti0.9Ox catalyst. Sm helped develop paths for fast electron transport, in which a charge transfer bridge was built between the Ce and Co, largely favoring the redox cycle. The nature of the acid sites, NOx adsorption, and the reactivity of surface adsorption species was characterized via in-situ DRIFTS. Moreover, the addition of Sm weakened the adsorption capacity of SO2 on the catalyst surface. We found that the electron transfer between SO2 and the activity sites was hindered on the modified catalyst.

Formation Mechanism of Monodispersed Polysilsesquioxane Spheres in One-Step Sol–Gel Method

Monodispersed polysilsesquioxane (PSQ) spheres with diameters from hundreds of nanometers to several microns have been successfully synthesized; however, the knowledge of their formation mechanism still lags behind. Herein, with methyltrimethoxysilane and 3-mercaptopropyl trimethoxysilane as model silicon sources, the formation process of PSQ spheres in the one-step sol-gel method was revealed for the first time by monitoring the time evolution of particle morphology, size, and size distribution via transmission electron microscopy and dynamic light scattering. A four-stage formation mechanism was proposed: rapid hydrolysis of organic silicon source and subsequent oligomer micelle nucleation, fast growing of nuclei particles and formation of their aggregates, followed by a further relatively fast growth of dispersed particles, and finally a slow growth to form monodispersed PSQ spheres. Due to the reversibility of hydrolysis and condensation reactions, thermodynamically unstable particles gradually transformed to hydrolytic monomers/oligomers and then regrew on the thermodynamically stable particles until the concentration of hydrolytic oligomers reached the dissolution equilibrium in the alkaline reaction solution. The variation of growth rate during the formation process and the effects of NH4OH concentration on the yield and particle size were investigated to facilitate analyses and understanding of the formation mechanism.

Three-dimensional electrochemical degradation of p-aminophenol with efficient honeycomb block AC@Ti-Cu-Ni-Zn-Sb-Mn particle electrodes

Emerging contaminants such as pharmaceuticals has been one of the most challenging environmental problems. In this work, we developed a one-step facile sol–gel method of loading TiO2, CuO, NiO, ZnO, Sb2O3 and MnO onto honeycomb block activated carbon (AC@Ti-Cu-Ni-Zn-Sb-Mn), further applying as particle electrodes in a three-dimensional electrochemical system for the efficient degradation of p-aminophenol (PAP). Factors associated with the preparation of AC@Ti-Cu-Ni-Zn-Sb-Mn particle electrodes were investigated. The AC@Ti-Cu-Ni-Zn-Sb-Mn particle electrodes were analyzed by scanning electron microscope (SEM), energy dispersive spectrum analysis (EDX), X-Ray Diffraction analysis (XRD), Brunner-Emmet-Teller (BET) and X-ray Photoelectron spectroscopy (XPS). The effects of conductivity, pH value, aeration intensity, current density, conductivity and initial concentration on PAP degradation were also studied. Importantly, the PAP degradation results show that the activity of the particle electrodes supported by block honeycomb activated carbon is much better than that of the particle electrodes supported by granular activated carbon. The removal efficiency of PAP achieved approximately 99.87% under the optimized condition. The pathway study suggested that the quinoneimine is the major intermediate during the three-dimensional electrochemical degradation and OH radicals play important roles in the reaction. Overall, its facile fabrication and efficient electrochemical degradation performance indicate that the proposed honeycomb block particle electrodes have potential for practical applications of refractory organic pollutants.