Journal of Porous Materials最新文献

To cater the ever growing energy demand and durability for modern applications like portable electronic gadgets, hybrid electric vehicles, etc., enormous research has been done to develop high capacity electrochemical energy storage devices. Among different allotropes of carbon, graphene, is emerged as an excellent candidate for energy conversion and storage applications because of its unique properties, including high specific surface area (2630 m²/g), good chemical stability and excellent electrical conductivity. To obtain high specific capacitance as well as high rate capability, the use of MnO₂ based composite materials is predicted as potential candidate. Strategies to modify supercapacitor performance of MnO₂ based composites are reported by various research groups. Polyaniline is one of the most studied conducting polymer due to good conductivity, environmental stability, low weight, easy synthesis on large scale and economic importance for industrial applications. In commercial supercapacitors, activated carbon is commonly used as electrode materials. Low energy density of carbon materials cannot be efficient for their effective use in energy storage applications. Thus, preparation of supercapacitors by using hybrid material with incorporation of metal oxides and conducting polymers in graphene can provide exceptional energy as well as power density. Nanocomposite materials have attracted much attention due to the synergetic effects between the components which shows better electrical properties. Further, the improvement in the electrical properties in hybrid materials is attributed to the direct interfacial interaction. In this study, specific capacitance of Polyaniline/MnO₂/Graphene/Graphene oxide composite material was found to be 1882.32 (Fg⁻¹) with symmetric galvanostatic charge/discharge curves and 97.61% capacitance retention after 6063 cycles in cycle performance.

Thermal insulation materials must exhibit superior mechanical properties alongside exceptional thermal insulation conductivity. However, traditional porous ceramics often struggle to meet these dual requirements simultaneously. In high-entropy materials, the phonon scattering induced by lattice distortion effects can significantly reduce the thermal conductivity of ceramics, thus opening new avenues for the design of novel thermal insulation materials. Inspired by the high-entropy effect, this study employed solid-state reaction methods to synthesize (Ce_0.2Zr_0.2Ti_0.2Sn_0.2Ca_0.2)O_2−δ (CZTSC) high-entropy ceramics at various temperatures, investigating their phase constituents, microstructural characteristics, and mechanical properties, while exploring the optimal sintering temperature. Additionally, a pore-forming agent method was utilized to fabricate monophasic CZTSC porous ceramics with different porosities at 1400 °C. Specifically, when the pore-forming agent content was 20 wt%, the sample exhibited an apparent porosity of 42.82%, with a low thermal conductivity of 0.57 W·m^− 1·K^− 1, a low thermal diffusivity of 0.406 mm²·s^− 1, and a relatively high compressive strength of 32.49 MPa. The current investigation underscores the promising prospects of porous CZTSC ceramics in the field of thermal insulation.

The present study reports in-situ synthesis of porous silica-ruthenium composite catalyst for hydrolysis of ammonia borane. The in-situ synthesized catalyst precursors were prepared via sol-gel based methods using surfactant micelles of cethyltrimethylammonium bromide (CTAB) to form well-ordered nanopores in the precursor particles. The precursors consisted of spherical particles with the diameter of ca. 20–60 nm and nanopores with the diameter of ca. 2–3 nm were included in the precursor particles. The specific surface areas and pore volumes decreased with increasing of ruthenium content, while their catalytic activity for hydrogen generation from aqueous ammonia borane solution was the same level regardless of the ruthenium contents. The catalytic activity was effectively improved via reflux procedure of the precursors through removing residual compound probably originated from CTAB with maintaining dispersion of the active ruthenium species after the procedure.

Methylene blue is one of the most common compounds in mutagenic, teratogenic and carcinogenic dye wastewater. Adsorption is a simple and effective method for efficient treatment of organic wastewater. In this study, amine functionalized Al-SBA-15 mesoporous molecular sieves were prepared for adsorption of methylene blue solution. Solid waste fly ash was utilized as a cheap source of silica, which was combined with templating agent P123 to form Al-SBA-15 molecular sieves. Then silane coupling agent (APTES) was used to graft amine groups on the surface of Al-SBA-15 to improve the adsorption performance. The adsorption experiments showed that NH₂-Al-SBA-15 had the best adsorption performance, with 324 mg g⁻¹ against 200 mg L⁻¹ methylene blue solution in 500 min. But the adsorption of Al-SBA-15 was 311 mg g⁻¹. It proved that the functionalization increased the adsorption of methylene blue by the molecular sieve. Then the kinetic study was carried out, which showed that it conformed to the proposed secondary kinetics as well as Langmuir isothermal adsorption model. Then the effects of pH, adsorption temperature and methylene blue concentration on the adsorption performance were investigated. The optimal adsorption performance was obtained, and it resulted in the optimal adsorption pH value of 10, adsorption temperature of 25 °C, methylene blue concentration of 200 mg L⁻¹, and mass of adsorbent of 30 mg.

The application of porous aerogels for dye adsorption has proven to be an effective approach in wastewater treatment. In this study, bio-cellulose aerogels from coconut fibrils were successfully developed via the formation of physically cross-linking cellulose with non-toxic binders (polyvinyl alcohol (PVA) and xanthan gum (XTG)) resulting from a freeze-drying technique. The flexible aerogel composites demonstrated remarkably low density (27.59–47.76 g/cm³), high porosity (> 96.0%), compressive Young’s modulus (3.82–12.66 kPa), a specific surface area of 518.01 m²/g, and a desorption average pore diameter distribution of 3.77 nm. These aerogels were tested for crystal violet (CV) and methyl orange (MO) adsorption to evaluate their effectiveness in treating dye-polluted water via various conditions such as contact time, pH values, initial concentrations, and temperature. The dye adsorption process reached equilibrium after approx. 30 min and strictly followed pseudo-second-order and the Redlich-Peterson model. FT-IR and SEM-EDX analyses proved that the adsorption mechanism is primarily ascribed to the hydrogen bonding, electrostatic, π-π, and Vander Waals interactions between aerogel and dye molecules. The eco-friendly synthesis of recycled cellulose aerogels from coconut fibrils using green chemicals holds great promise for dye elimination.

Graphical Abstract

Antibiotics present significant environmental risks due to their persistent and mutagenic properties. This study introduces an innovative method employing an aqueous walnut husk extract to synthesize multiwalled carbon nanotubes (MWCNTs) with enhanced adsorption capabilities. These capabilities are further improved by integrating bimetallic iron–copper (Fe–Cu) nanoparticles onto the MWCNT surface, resulting in MWCNT@Fe–Cu composites. The adsorption capacities for amoxicillin in aqueous solutions were determined to be 613.97 mg/g for MWCNT and 769.23 mg/g for MWCNT@Fe–Cu. Characterization of these materials was carried out using FTIR, BET, TGA, FESEM, EDX, and XRD methods. The specific surface areas measured were 126 m²/g for MWCNT and 229 m²/g for MWCNT@Fe–Cu. Adsorption data adhered to a pseudo-second-order kinetic model and the Langmuir isotherm model provided the best fit. Thermodynamic analysis indicated that the adsorption process was spontaneous and endothermic. The MWCNT@Fe–Cu composite demonstrated remarkable stability after six regeneration cycles, whereas the stability of MWCNT alone diminished over the same period. This enhanced stability is attributed to the Fe–Cu nanoparticles, which prevent agglomeration in aqueous environments. The walnut husk extract is crucial for the formation of carbon nanotubes, offering a sustainable and eco-friendly solution to the problem of antibiotic pollution in water systems.

Traditional methods for the separation of oil and water exhibit numerous flaws, including limited decontamination capacity, incomplete separation, complex operation, and environmental pollution. Although some film materials are widely used in the process of separating oil and water, they also present challenges such as susceptibility to contamination and high expenses. Here, three types of films are fabricated using waste glass as the raw material by incorporating diverse additives for achieving distinct microstructures. Different micromorphologies resulted in different film properties, with the superhydrophilic and underwater superoleophobic films prepared with KOH as an additive showing exceptional performance compared to the others, with separation efficiencies is 99.97%. Meanwhile, the preparation method of this film is characterized by low cost, simple operation and green environment. As a result, this has the potential for practical applications in the separation of oil and water.

A kind of new zirconium phosphonate material ZrDP with multilevel porous structure and high surface area (about 408.6 m²/g) was synthesized by the reaction between 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl-tetrakis(methylphosphonic acid) (DOTMP) and Zr⁴⁺ ions in acidic water solution. Micropores with diameter about 0.64 nm from 1,4,7,10-tetraazacyclododecane in DOTMP and the pores with diameter about 1.68 nm from structure were found in the material. Some metallic ions were coordinated on the skeleton of ZrDP to form composites M@ZrDP and Cu(II)@ZrDP exhibited high catalytic activity in the selective oxidation reaction from benzyl alcohol to benzaldehyde with 90.2% selectivity.

Introducing the second mesopores into SAPO-11 molecular sieve will be much helpful to improve the catalytic performance of its metal-supported catalysts in hydroisomerization of normal alkanes. In current paper, polyvinyl alcohol phosphates with different phosphorus contents were prepared and employed as mesopore template to prepare hierarchical SAPO-11. The effects of phosphorus content and concentration on the properties including mesopore structure, acidity and morphology of the prepared SAPO-11s have been investigated. The results showed that with appropriate phosphorus content and template concentration, PPVAs efficiently directed the generation of regular mesopore structure, extended the surface area and improved the acidity of the SAPO-11 molecular sieves. Pt/SAPO-11 bi-functional catalysts were prepared and their catalytic performances in hydroisomerization of n-hexane were evaluated. The highest conversion read 59.3%, while the optimal selectivity of branched hexanes was 86.5%.

A double-layer broadband antireflective coating with remarkable optical performance and superhydrophilicity has been designed and prepared based on TiO₂-SiO₂ hybrid films. The synthesis of TiO₂-SiO₂ composite sols is carried out using titanium isopropoxide and tetraethyl orthosilicate as raw ingredients in an acid-catalyzed system. The TiO₂-SiO₂ hybrid film with refractive index of 1.61 (at 550 nm) is used as the bottom layer, and the other mesoporous TiO₂-SiO₂ film templated by an ethylene oxide-propylene oxide-ethylene oxide triblock copolymer is employed as the top layer to achieve the design concept of quarter-half structure. The average transmittance reaches 99.17% in the visible spectral range. The water contact angle of the coating is observed to reduce significantly from 47° to 9.75° by introducing ammonia treatment, indicating that the double-layer coating exhibits superhydrophilicity. Simultaneously, due to the doping of TiO₂, the double-layer coating possesses a high abrasion resistance. The prepared double-layer antireflective coating has potential application in various areas, like solar cells, eyeglasses and windows of high-rise buildings, etc.