Chitosan composite aerogels doped with oilfield drill cuttings for arsenic removal: A combined experimental and computational approach.

Thermally insulated C/SiC/SiBCN composite ceramic aerogel with enhanced electromagnetic wave absorption performance

A one‐pot biosynthesis of an aerogel composite based on attapulgite clay/bacterial cellulose to remove Pb²⁺ ion

In this study, the effective TiO2/Ag composite antibacterial aerogel powder is prepared by facile sol–gel method and ethanol supercritical technology. The surface morphology, structural properties, and chemical components are monitored by scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and energy disperse spectroscopy (EDS). Meanwhile, absorbance spectra and specific surface area of TiO2/Ag composite aerogel are characterized by UV-Vis spectra and Brunauer–Emmett–Teller. The TiO2/Ag composite aerogel with Ti/Ag molar ratios of 10:1, 30:1, 50:1 are measured for its antibacterial property by using Escherichia coliform (E.coli) and Staphylococcus aureus (S. aureus). The results show that the size of TiO2 and Ag nanoparticles are 40 nm and 25 nm, respectively. Simultaneously, the obtained composite aerogel with a porous structure possessed a surface area of 148 m2/g, an average pore size 11.5 nm, and a pore volume 0.39 cm3/g. With the increase of Ag content, the antibacterial properties of composite aerogel are greatly improved compared with pure TiO2 aerogel. When Ag/Ti molar ratios was 1:10, the highest antibacterial rate can up to 99%, and the inhibition bands of E. coli and S. aureus are 23 mm and 19 mm, respectively.

Study of activated nitrogen-enriched carbon and nitrogen-enriched carbon/carbon aerogel composite as cathode materials for supercapacitors

A multifunctional gelatin-based aerogel with superior pollutants adsorption, oil/water separation and photocatalytic properties

Ulvan-based composite aerogels for efficient methylene blue adsorption.

The heat insulation ability and thermal stability of thermal protection materials play extremely important role in the thermal protection of aero-engines under high temperature. Herein, we design the carbon-SiO2-Al2O3 (CSA) composite aerogel through thermochemical restructuring from the phenol-formaldehyde resin-SiO2-Al2O3 (PSA) composite aerogel. This thermochemical restructured aerogel not only shows better adhesion property under room temperature but also possesses higher thermal stability and desirable heat insulation ability under high temperature. Taking the PSA-0.5 composite aerogel as an example, the compressive strain-stress test unveils that it can be compressed by 66% without catastrophic collapse, which is beneficial for the adhesion with the metallic matrix. Meanwhile, the transmission electron microscopy and scanning electron microscopy images exhibit the unbroken three-dimensional structure for the CSA-0.5 composite aerogel, which confirmed the structural stability of the composite aerogel after thermochemical restructuring. The thermal cycle test indicates that the weight loss of the CSA-0.5 composite aerogel is only ca. 8%, firmly confirming its thermal stability. Importantly, the thermal conductivity of the CSA-0.5 composite aerogel ranges from 0.024 to 0.083 W m-1 K-1, indicating the superior performance of heat insulation. Moreover, the numerical simulation is carried out to validate the thermal protection effect of the CSA-0.5 composite aerogel as a thermal protection layer. Together with laminated cooling, it could enhance the surface cooling effectiveness of the metallic matrix to above 0.8. Briefly, this work paves a new pathway for efficient thermal protection materials of aero-engines via the rational design of the thermochemical restructured composite aerogel under the guidance of ANSYS numerical simulations.

As a classic component of non-steroidal anti-inflammatory drug (NSAID), diclofenac has the anti-inflammatory, analgesic and antipyretic effects. As a result, the medical wastewater discharged from some diclofenac pharmaceutical factories may contain a certain amount of diclofenac. This pollutant is toxic and harmful to livestock, and if the livestock have digested diclofenac, it will affect their cellular metabolism process, cellular components and protein catalysis, which may even cause mass deaths under severe situation. An effective treatment method for this pollutant is to adopt composite aerogel adsorption. This paper briefly introduces the modification plan of cellulose and the process of using cellulose to adsorb diclofenac sodium (DCF), compares the adsorption effects before and after modification, and proposes a new direction to treat this kind of pollutant based on the comparison results. In this paper, by using cotton fiber as the material and polyvinylamine as the modifier, the hydrothermal synthesis method is employed to prepare the rGO/cellulose composite aerogel material, and the characterization analysis of its structure and performance is also conducted. The characterization results of SEM, EDS, XRD. FTIR etc. show that the composite aerogel material prepared in our experiment has maintained the crystal structure of cellulose, which has obvious 3D porous structure, and its specific surface area reaches 354.7m2/g. In addition, the material surface contains abundant amino, hydroxyl, C=N and other functional groups. Secondly, with diclofenac sodium as the targeted pollutant, this paper investigates the performance and mechanism of using rGO/cellulose composite aerogel to adsorb diclofenac sodium. The experimental results show that the rGO/cellulose composite aerogel presents outstanding performance in adsorption of DCF, which is significantly superior to the performance of cellulose aerogel material. When the rGO/cellulose composite aerogel and the cellulose aerogel are used to adsorb DCF, their maximum adsorption capacities are 242.94mgg-1 and 47.82mgg-1, respectively. In addition, the process of using composite aerogel to adsorb DCF satisfies the Langmuir isothermal adsorption model and the pseudo-second-order kinetic model, which indicates that this adsorption is chemical adsorption mainly consisting of monolayer adsorption. The thermomechanical analysis shows that the adsorption of DCF using composite aerogel is spontaneous exothermic reaction. In the meantime, the composite aerogel has wider pH adaptability, and it presents great adsorption efficiency of DCF within the pH range of 4-10.

Facile fabrication of graphite-doped silica aerogels with ultralow thermal conductivity by precise control

MOFs compounds with open metal sites, particularly Cu-BTC, have great potential for adsorption and catalysis applications. However, the powdery morphology limits their applications. One of the almost new ways to overcome this problem is to trap them in a standing and flexible aerogel matrix to form a hierarchical porous composite. In this work, Cu-BTC/CNC (crystalline nanocellulose) and Cu-BTC/NFC (nanofibrillated cellulose) aerogel composites were synthesized using a direct mixing method by the addition of Cu-BTC powder to the liquid precursor solution followed by gelation and freeze-drying. Also, pure nanocellulose aerogels (CNC and NFC aerogels) have been synthesized from cellulose isolated from peanut shells. Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectra, and X-ray diffraction (XRD) were utilized to evaluate the structure and morphology of the prepared materials. The adsorption ability of pure CNC aerogel and Cu-BTC/NFC aerogel composite for organic dye (Congo Red) and heavy metal ion (Mn7+) was studied and determined by the UV–Vis spectrophotometry and inductively-coupled plasma optical emission spectrometry (ICP-OES), respectively. It was concluded that Cu-BTC/NFC aerogel composite shows excellent adsorption capacity for Congo Red. The adsorption process of this composite is better described by the pseudo-second-order kinetic model and Langmuir isotherm, with a maximum monolayer adsorption capacity of 39 mg/g for Congo Red. Nevertheless, CNC aerogel shows no adsorption for Congo Red. Both CNC aerogel and Cu-BTC/NFC aerogel composite act as a monolith standing solid reducer, which means they could remove permanganate ions from water by reducing it into manganese dioxide without releasing any secondary product in the solution.

Graphene oxide (GO) exhibits a strong adsorption capacity for the removal of heavy metal ions from liquids, making it a topic of increasing interest among researchers. However, a significant challenge persists in the preparation of graphene oxide-based adsorbents that possess both high structural stability and excellent adsorption capacity. In this paper, a green and environmentally friendly ternary composite aerogel based on graphene was successfully synthesized. The adsorption capacity of graphene oxide was enhanced through diethylenetriaminepentaacetic acid modification, while the incorporation of composite carboxymethyl cellulose improved the structural stability of the composite aerogel in liquid. The composite aerogel demonstrates robust interactions between its components and features a multiscale porous structure. Adsorption tests conducted with Pb(II) revealed that the GO/DTPA/CMC (GDC) composite aerogel exhibits a favorable adsorption capacity. The study of adsorption kinetics and isotherms indicated that the adsorption process follows the quasi-secondary adsorption model and Freundlich adsorption model, suggesting a chemical multilayer adsorption mechanism, and the maximum adsorption capacity for Pb(II) ions was 521.917 mg/g based on the quasi-quadratic kinetic model fitting. X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) analyses, performed before and after adsorption, confirmed that the adsorption of Pb(II) primarily occurs through chelation, complexation, proton exchange, and electrostatic interactions between ions and active sites such as hydroxyl and carboxyl groups. This study presents an innovative strategy for simultaneously enhancing the adsorption properties of graphene oxide-based composite aerogels and ensuring solution stability.

Ambient pressure drying synthesis of Cs0.33WO3/SiO2 composite aerogels for efficient removal of Rhodamine B from water

ABSTRACTIn order to develop efficient and environment benign sorbents for water purification, a simple hydrothermal process for fabrication of the halloysite (HNTs)/graphene oxide (GO) composite aerogels comprising HNTs anchored on graphene oxide sheets was developed. The morphology and structure of the materials were characterized by scanning electron microscopy (SEM), nitrogen adsorption-desorption, and Fourier transform infrared (FT-IR). The results demonstrated that the composites exhibit large surface area (SBET = 361.3778 m2·g−1) and high pore volume (Vp = 1.2432 cm3·g−1) with only 10 wt% of HNTs, higher than that of the ture GO aerogel (SBET = 142.8816 m2·g−1, Vp = 0.6106 cm3·g−1). The adsorption properties of the pure GO aerogels and n-HNTs/GO composite aerogels with 10 wt% of n-HNTs were measured using a UV-Vis spectrophotometer. The results reflected that the adsorptivity of MB by the n-HNTs/GO composite aerogels was 99.3%, much higher than the pure GO aerogels (89.4%).

Ultra-low-density graphene nanosheet (GNS)/carbon composite aerogels (CAs) were prepared via GO (graphene oxide)/RF (resorcinol–formaldehyde) aerogel composite, supercritical fluid drying, and carbonization. Graphene oxide was found to act as an efficient anti-shrinkage additive in the carbonization process, making the linear shrinkage ratios decrease from 78 % to only 10 % (25 % GO content). The density of the aerogels thus decreases from 115 to 24.4 mg cm−3. 25 % GO-composited aerogel exhibits over two times modulus increase and over 11 times specific modulus increase in comparison with pure carbon aerogel. The microstructure results show that GO is fully cross-linked with RF polymers, makes the reaction more sufficient and ultimately strengthens the nanostructure to withstand the damage of carbonization. The resultant composite carbon aerogels exhibited super high specific surface area (as high as 2899 m2 g−1), good mechanical property, and high adsorption capacity of 403 mg g−1 for methylene blue.

A theoretical study on the cyclopropane adsorption onto the copper surfaces by density functional theory and quantum chemical molecular dynamics methods