Journal of Porous Materials最新文献

Using the spray pyrolysis process, undoped and cerium-doped zinc oxide thin films were prepared at 400 °C on a completely cleaned glass substrate with various doping concentrations of Ce (2, 4, 6, and 8 at%). Optical, electrical, structural, surface morphology, surface roughness, chemical composition, and photoluminescence investigations have been performed on these films. According to structural analysis via X-ray diffraction (XRD), the pure and Ce doped ZnO thin films were polycrystalline with a hexagonal wurtzite structure and a (002) plane orientation. The ZnO thin film doped with 6 at% Ce has a minimum of 31.72 nm-sized crystallites. According to the SEM images, the surface morphology of the deposited thin films is porous and results in a uniform distribution of nanoscale grains, which is beneficial for solar applications. The particle size and surface roughness of the produced films decreased with increasing Ce doping, according to the AFM findings. Optical experiments show that all the produced films are transparent in the visible region, and that the transmission is high in 92% for 6 at% of Ce doped ZnO sample, it is appropriate for use in optoelectronic devices. The optical band gap decreases 3.56 eV to 3.11 eV with increasing Ce doping. The PL investigations revealed that the maximum intensity of the UV emission band was 6 at% Ce, indicating an improvement in crystallinity. Electrical studies have shown that with increasing hall mobility, the carrier concentration, conductivity, and resistivity decrease. The lowest electrical resistivity, and highest electrical conductivity for the 6 at% Ce-ZnO sample are 1.21 × 10^− 3 Ω cm, and 825.62 Ω⁻¹ cm^− 1, respectively. These findings indicate that Ce-doped ZnO is a good material for use in transparent conductive oxides applications.

We present, a facile method for the synthesis of block co-polymer (BCP) of [(PLA)-b-(Car)], (PLA-Poly Lactic acid and Car-Carbazole). BCP results in the design and development of cone and ice-cream cup-shaped frustums with nanoscale porosity for bio-sensing and drug delivery applications. [(PLA)-b-(Car)] was conjugated through condensation polymerization between amine proton and hydroxyl groups of PLA and Car. Thermoplastic PLA is responsible for desired size, shape, and porosity over the surface. The size, shape, and morphology of the [(PLA)-b-(Car)] are tunable based on suitable solvents and thermal treatment. Interestingly, design of nanoporous hollow (half-broken coconut type) capsules has been carried out without using any precursors and surfactants. Synthesis of [(PLA)-b-(Car)] has been confirmed through the Fourier transform infrared (FTIR), nuclear magnetic resonance (¹H NMR). However, the morphology and surface properties of capsules were confirmed through field emission scanning electron microscopy (FE-SEM), Bruner Emmett Teller (BET), and atomic force microscopy (AFM) characterizations. The capsule size ranges from ~ 200 nm to 1 μm (in diameter) and porosity scales from ~ 60 to 80 nm. The hollow and porous surface of the capsules with biosensing and drug delivery applications can be considered as a unique and novel characteristic property of our invention. This kind of novel cone and ice cream cup-shaped hollow frustums can be used as a stimuli-responsive catalytic activity through the fluorescence measurement of cysteine and gold nanoparticle [(Cys)-(Au⁺)] for enhanced payload and biomedical applications.

Fe/N co-doped carbon material serves as a highly efficient catalyst for mineralizing of organic pollutants. In this study, Fe/N-doped porous carbon catalyst (FeNC-PC) was prepared by an economical and facile method using gelatin hydrogel as a template. The FeNC-PC catalyst was utilized to activate PMS and degrade tetracycline hydrochloride (TC). In the characterization of the FeNC-PC catalyst, Fe and N were homogenously distributed across the surfaces of the porous structure carbon. The FeNC-PC/PMS system exhibited excellent TC removal efficiency, achieving a 92.61% removal efficiency with a low catalyst dosage (0.15 g/L). It also demonstrated stable TC removal efficiency across a broad pH spectrum (3–9) and various anionic interferences (5–50 mM). Furthermore, ¹O₂ and O₂·⁻ were the main active species in the system. The degradation mechanical analysis suggested that Fe active sites, especially Fe²⁺, were crucial for accelerating the catalytic process. Pyridinic nitrogen and graphitic nitrogen also contribute to the high catalytic activity. The degradation pathways of TC were suggested through the use of LC–MS. As anticipated by quantitative structure–activity relationship research, the toxicity of TC degradation products was effectively mitigated. This study provided new insights for the synthesis of a more promising Fe/N co-doped catalyst.

In this study, composite foams containing chitosan (CHI) and boron doped-biphasic calcium phosphate (BCP) were developed using freeze-drying method. The quantities of BCP incorporated into the CHI matrix were introduced into the foams at three different ratios: 25 wt%, 50 wt%, and 75 wt%. The objective of this study was to investigate the microstructure, swelling, mechanical, and biological properties of boron-doped BCP/CHI-based composites. Scanning electron microscopy (SEM) micrographs revealed that all of the composites exhibited open and interconnected pore morphologies. The FTIR spectra demonstrated that boron doping interacts with the hydroxyl and phosphate groups in the CHI/BCP composites, which is evidenced by changes in peak intensities. It was found that low amounts of boron positively affected the compressive strength and in vitro cytotoxicity of the composites. Following simulated body fluid treatment, the boron-doped BCP/CHI composites exhibited robust apatite layer formation. These results indicated that the composite foams with modified physical and mechanical characteristics show considerable promise for use as composite materials in biomedical applications, including bone scaffolds or wound dressings.

With the development of Chinese economic, watershed pollution situation is getting worse and gradually attracts people’s attention. Graphene aerogel (GA) is an ideal material for removing water pollution, due to its high porosity, high specific surface area, and stability. A green and convenient method for GA synthesis was proposed by using graphene oxide dispersion as raw material, triethanolamine as reducing agent, and Blue Moon hand sanitizer as surfactant. The microstructure, hydrophobic and mechanical properties of GA were thoroughly characterized. The adsorption of the prepared aerogel for dichloromethane and ethyl acetate was 240 and 174 times of its own mass, respectively. Moreover, it shows good recirculation adsorption capacity under the 100 compression-adsorption cycles of 50% maximum stress. A paraffin-GA phase change material with good thermal conductivity was also prepared and characterized. This indicates that the prepared GA has a wide range of applications.

Pt-xCe@HZSM-5-op catalysts with different Ce contents were successfully synthesized via a hydrothermal method to increase the added value of iso-butane. The effects of the introduction of metal into zeolite on the relative crystallinity, pore characteristics, morphology, metal state and acidity were investigated by X-ray diffraction, N₂ adsorption‒desorption, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, temperature-programmed desorption of ammonia and pyridine infrared spectroscopy. The introduction of Pt and Ce species decreased the amounts of weak acid sites and increased the strong acid content of HZSM-5 catalyst. And it also adjusted the distribution of B acid and L acid. Moreover, the effect of varying Ce content was investigated on the catalytic cracking performance of Pt-xCe@HZSM-5-op catalysts. Among the catalysts, Pt-0.25Ce@HZSM-5-op catalyst exhibited the best catalytic performance for iso-butane cracking at 625 °C.

The growing need for sustainable energy has led to a great deal of interest in creating effective and reasonably priced non-precious electrocatalysts as substitutes for precious metal-based electrocatalysts, which are expensive and frequently show poor long-term stability under extreme reaction conditions, making them less useful for sustainable energy solutions. In this study, we introduce Mn/CoS@S-g-C₃N₄, a novel electrocatalyst composed of manganese-doped cobalt sulfide integrated with sulfur-doped graphitic carbon nitride (S-g-C₃N₄), synthesized through a simple co-precipitation method. The synergy between Mn and CoS within this composite provides an optimized electronic structure, enhancing the transfer of electrons and presence of S-g-C₃N₄ serves as both a stabilizing matrix and a conductive support, exposing more active sites which enhances both performance and durability. This Mn/CoS@S-g-C₃N₄ catalyst demonstrated low overpotentials of 306 mV for OER and 404 mV for HER at a current density of 10 mA/cm² in 1 M KOH solution, alongside favourable Tafel slopes of 63.72 mV/dec for OER and 73.22 mV/dec for HER. Additionally, the use of earth-abundant and low-cost elements (Mn and Co) makes Mn/CoS@S-g-C₃N₄ a highly economical choice, addressing both performance and cost-effectiveness in water splitting applications.

To understand the origin of product selectivity, vinyl pyridine (VP) functionalized mesoprous silica nanocomposites were synthesized via two different methods (co-condensation and post grafted polymerization method) for possible influence of synergism in Henry reaction. The physicochemical characterization method (PXRD, N₂-adsorption–desorption, FT-IR, TGA and SEM–EDX, etc.) of the functionalized nanocomposites revealed the retention of mesoporous structural order. The synthesized nanocompostes were exploited for catalytic activity studies for the condensation of 4-methylbenzaldehyde with nitroethane in the liquid phase. The catalytic activity studies showed a significant influence of synthesis methodology for the competitive selectivity of the desired products (Scheme 1). All the standard reaction parameters were optimized to yield better conversion and selective product. Finally, the mechanism of the product formation is proposed and explained.

The temperature evolution of spatial organization and crystal structure of nanocomposite materials (NCM) based on porous glass with potassium nitrate (KNO₃) introduced from a saturated aqueous solution are studied using small-angle X-ray scattering and neutron diffraction methods on heating and cooling in the temperature range of 300–450 K. It is shown that the ferroelectric γ- phase in this NCM becomes predominant both upon heating and upon cooling. The phase diagram of potassium nitrate in NCM on cooling is established. The average size of coherent scattering region for the γ-phase is determined (< L > ∼ 100 Å), and it is practically independent of temperature. From the treatment of small- angle X-ray scattering data, the temperature dependence of the radius of gyration R_g is obtained. The average R_g value is 270(20) Å and does not depend on temperature on heating and cooling in the range RT – 450 K. On a spatial scale from 20 to 200 Å, potassium nitrate embedded in mesoporous glasses forms a developed surface fractal characterized by a Q^-α scattering law with α ∼ 3.52 in small-angle X-ray scattering. It is found that a significant part of potassium nitrate in the nanocomposite is in the amorphous phase.

In response to the global push for environmentally friendly technologies and sustainable practices, we have developed an advanced SBA-15-Zn/Cu catalyst that significantly enhances biodiesel production from waste cooking oil. SBA-15, a mesoporous silica, was first functionalized with organic amine and then treated with zinc and copper using a novel and cost-effective modification technique. This approach preserves the structural integrity of SBA-15 while enhancing its catalytic properties. Comprehensive characterization techniques, including powder X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDAX), Brunauer-Emmett-Teller (BET) surface area analysis, Barrett-Joyner-Halenda (BJH) pore size distribution, transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR), confirmed the successful incorporation of zinc (Zn) and copper (Cu), thereby validating the structural stability of the catalyst. The SBA-15-Zn/Cu catalyst exhibits superior performance in the transesterification reaction, crucial for biodiesel synthesis, achieving 84% waste cooking oil conversion and 61% biofuel yields through various optimization techniques. This innovated catalyst not only improves biodiesel production efficiency but also aligns with sustainable practices, making it both industry and environment friendly via its significant reusable capacities up to 5 consecutive cycles.