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A salt-resistant solar-driven interface evaporator was prepared from silk fibroin with a directional channel structure, coated with natural black melanin for solar light harvest and photothermal conversion. This silk fibroin-melanin (SF-melanin) solar-driven evaporator achieved a water evaporation rate of up to 2.49 kg m−2 h−1 under 1 sun beneficial from the intrinsic hydrophilicity of silk fibroin, the directional channel structure, and the high efficiency of solar light harvest and photothermal conversion of natural black melanin. The directional channel structure also facilitates the rapid dissolution of salt crystals back to the native solution, enabling stable performance during the long-term solar-driven desalination process. Moreover, this SF-melanin solar-driven evaporator can totally be degraded in soil since all of its components are bioresource. This high efficient, salt-resistant, biodegradable solar-driven evaporator will further promote the practical application of solar-driven evaporator. [Display omitted] • Silk fibroin aerogel with directional channel structure was obtained by liquid nitrogen-assisted directional freezing method. • Directional silk fibroin-melanin (D-SF-M) evaporator has excellent water-transport capability and broadband light absorption. • D-SF-M evaporator exhibits outstanding solar steam generation and desalination performance. • D-SF-M evaporator is totally biodegradable and environmental friendly. [ABSTRACT FROM AUTHOR]

Water scarcity and pollution have become major obstacles to sustainable global development. The development of a versatile platform that can simultaneously produce clean water and remediate pollutants from water is highly desirable but still difficult to realize. Herein, to address this challenge, we have developed a CY@PPy@Ag aerogel with excellent photothermal and photocatalytic capabilities through a freeze-drying process, followed by polypyrrole coating and Ag deposition. The excellent characteristics, including broad-spectrum light absorption (97.2%), localization of converted heat, rapid water transport, and porous open microchannels, enabled it to act as an advanced solar evaporator for efficient and continuous steam generation without salt crystallization. Moreover, the high evaporation rate (1.51 kg m−2 h−1) was maintained even in high concentrations of brine and real seawater. Taking advantage of its enhanced photocatalytic performance, organic dyes in water could be rapidly and completely decomposed by the CY@PPy@Ag aerogel under solar irradiation, and this photodegradation process was significantly accelerated with the help of NaBH 4. This work is expected to provide a one-stone-two-birds strategy to simultaneously achieve clean water harvesting and pollution remediation, which holds great promise in the fields of solar energy harvesting, wastewater treatment, and seawater desalination. [Display omitted] • A versatile aerogel platform has been developed. • Efficient solar-powered interfacial water stream generation was achieved. • Rapid photodegradation of organic pollutants in water was realized. • One-stone-two-birds performance was realized. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of amine-impregnated polymer aerogels for CO 2 capture represents a groundbreaking advancement in combating the urgent challenges of carbon dioxide (CO 2) emissions and climate change mitigation. The traditional way of synthesizing aerogels for CO 2 capture is to use a one-step gelation process without functionalizing the aerogel, which, to some extent, has low CO 2 capture capacity and kinetics. This study finds a method of synthesizing the functionalized aerogel, which has high CO 2 adsorption capacity, faster kinetic, and is more stable. The polymer aerogel was developed using an oil-water emulsion polymerization method, followed by freeze-drying. It was impregnated with a mono-ethanolamine (MEA) solution to enhance CO 2 adsorption. The performance of the amine-impregnated poly (AAm-co-AAc) aerogels was tested in a continuous adsorption column filled with aerogel. The adsorption results showed the amine-impregnated aerogels having an amine equilibrium uptake value of 40% had significantly improved CO 2 capture capacity up to 2.34 mmole g−1 at 1 bar pressure, 25 °C reaction temperature, and 10 ml/min flow rate. The polymeric aerogel has a very fast adsorption rate, as it can capture 90% of its maximum capacity within just 10 minutes. Then the kinetic data of the CO 2 adsorption was modelled and found to best fit on both pseudo-1st and 2nd-order kinetic models, proposing that the adsorption mechanism on aerogel was controlled by surface diffusion and chemisorption. Furthermore, the isotherm data were evaluated and observed to be best represented by the Langmuir isotherm model, suggesting monolayer formation on the aerogel. After five adsorption-desorption cycles, the amine impregnated poly (AAm-co-AAc) aerogel was able to preserve the initial capacity without a significant decrease. These findings underscore the immense ability of amine-impregnated poly (AAm-co-AAc) aerogels as highly efficient adsorbents for CO 2 capture, thus offering a speedy adsorption process and showing stable regeneration capacity, thereby exhibiting greater industrial application potential. [Display omitted] • An emulsion polymerization method was used to synthesize aerogels for CO 2 capture capacity. • The morphology of the aerogel is fibrous, contributing to its high amine uptake. • Its CO 2 adsorption capacity is up to 2.34 mmole g−1 at 25°C, and regeneration stability is five cycles. • The aerogel exhibits a rapid adsorption rate, capturing 90% of its capacity within 10 minutes. [ABSTRACT FROM AUTHOR]

Despite the promising potential of zeolitic imidazole framework-8 (ZIF-8) for dye adsorption, addressing challenges such as aggregation and recycling difficulties remains essential. Herein，a novel three dimensional (3D) carboxymethyl cellulose (CMC), graphene oxide (GO) and ZIF-8 hybrid aerogel (CGZ-3) was prepared via blending ZIF-8 into the CMC-GO matrix. The structure and composition of CGZ-3 were characterized by SEM, FT-IR, TG and XPS. Adsorption experiments were conducted to optimize various parameters affecting the behavior of methylene blue (MB) adsorption. The composite aerogel exhibited an obvious lamellar network structure, with a surface rich in oxygen-containing functional groups such as -OH and -COOH. CGZ-3 demonstrated a rapid adsorption rate for MB, achieving a removal efficiency of 96% within 15 minutes. The entire adsorption process was spontaneous and endothermic, consistent with the pseudo-first-order kinetic model and Langmuir adsorption isotherm model. The maximum theoretical adsorption capacity was 427.35 mg/g at 298 K. Selective adsorptions tests demonstrated high selectivity of the composite aerogel for MB, and dynamic adsorption further confirmed the exceptional adsorption capacity of CGZ-3. After five cycles of adsorption-desorption, the MB removal rate remained above 95%, with an adsorption capacity exceeding 240 mg/g, highlighting the stability and reusability of CGZ-3. Collectively, the CGZ-3 would be a potential material for the adsorptive removal of MB in practical water treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Although the rapid evolution of electromagnetic wave technology make much progress to society, but has also caused electromagnetic pollution, which poses risks to health, information security, and disrupts communication and device operation. The development of new Electromagnetic Interference (EMI) shielding materials, especially those that are lightweight, easy to process and high shielding efficiency, has become the key to overcoming this challenge. In this study, MXene nanosheets with few layers were fabricated by chemical etching with lithium fluoride (LiF) and hydrochloric acid (HCl). Subsequently, the unidirectional freeze-drying method and vacuum-assisted impregnation method were applied to fabricate polyimide@ polypyrrole/MXene (PI@PPy/MXene) composite aerogel with oriented structure. The electromagnetic shielding properties of the oriented PI@PPy composite aerogel were modulated by changing the polymerization time of PPy to control its conductivity. When the polymerization time was set as 7 h, the oriented PI@PPy composite aerogel showed the highest EMI efficiency, the value of EMI SE was 19.36 dB. With the introduction of MXene, the EMI SE of the PI@PPy/MXene composite aerogel was increased compared to PI@PPy and reached to 32.64 dB. The improvement in electromagnetic shielding performance was attributed to the co-enhancement among the PI aerogel with oriented structure, PPy and MXene, which is the result of the synergisic effect of Multiple reflection losses and polarization losses within the aerogel. The infrared thermography at 200°C showed that with increasing PPy polymerization time, the external temperatures of the samples are 40.3°C, 44.8°C, 51.4°C, 55.4°C and 48.6°C, demonstrating the excellent thermal insulation properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing active and stable electrocatalysts for oxygen evolution reaction is of great significance to generate oxygen and hydrogen by seawater electrolysis, which however remains some issues that high energy consumption and chloride corrosion. Here we pioneered a polymer/inorganic hybrid engineering strategy for achieving excellent salt resistance solar evaporation and oxygen evolution performance (OER). The La 0.9 Sr 0.1 CoO 3 /nickel foam–cellulosic aerogel (LSC1/NF–CA) was synthesized by engineering Trimethylamine N–oxide (TMAO) polymer brush onto the surface of hybrid aerogels composed of La 0.9 Sr 0.1 CoO 3 /Ni foam (LSC1/NF) and cellulose/polyvinyl alcohol, which has good hydrophilic features, intrinsic solar capture capacity, and stable OER performance in seawater. Benefiting from the synergy of solar desalination with surface hydration effect of TMAO, the LSC1/NF–CA presents a superior catalytic activity, requiring a lower overpotential of 341 mV and a tafel slope of 58.2 mV dec−1 at 10 mA cm−2 under 6.0 sun illumination. Our results establish a new strategy that can guide the design of stable and efficient polymer/inorganic hybrid catalysts, which shows a promising prospect as alternatives to noble metal–based catalysts for seawater splitting. The synergy effect of surface hydration effect of TMAO polymer brush and solar interfacial desalination of LSC1/NF-CS/PVA ensured the composite require a low overpotential of 341 mV to reach a current density of 10 mA cm−2 in alkaline salty water under 6 kW/m2 solar irradiation. [Display omitted] • An efficient salt–tolerant polymer/inorganic hybrid electrocatalytic system was constructed by in-situ assembling the inner perovskite La 0.9 Sr 0.1 CoO/Ni with the outer cellulose/Trimethylamine N–oxide polymer. • Surface hydration effect of Trimethylamine N–oxide polymer brush endows the La 0.9 Sr 0.1 CoO 3 /nickel foam–cellulosic aerogel with excellent salt resistance property. • Benefited from the photothermal conversion property of La 0.9 Sr 0.1 CoO 3 /nickel foam, the LSC1/NF–CA composite required an overpotential of 341 mV to obtain a current of 10 mA cm−2 for OER in simulated seawater. [ABSTRACT FROM AUTHOR]

Since the lotus effect was reported by Barthlott and Neinhuis in 1997, superhydrophobic and superoleophobic materials have received much attention due to special rough morphology and great potential applications in self-cleaning, anti-fouling, corrosion-resistance, and other fields. However, the conventional preparation process of superamphiphobic materials is complicated, including pre- and post-treatments which are used to achieve micro-nano hierarchical structures and low surface energy. In this study, we used methyltrimethoxysilane (MTMS) and 1,1,2,2- tetrahydroperfluorodecyltrimethoxysilane (FAS-17) as precursors and successfully prepared superamphiphobic FAS-17/MTMS composite aerogel via facile sol-gel method. Three-dimensional networks and long fluorocarbon chains formed micro-nano hierarchical structures. As-prepared aerogels had water contact angle (WCA) of 153.68°, oil contact angle (OCA) of 156.28°, water sliding angle (WSA) of 3.32° and oil sliding angle (OSA) of 4.57°, suggesting excellent superamphiphobic performance. Besides external superamphiphobicity, the cross section of sample also exhibited great liquid-repellency with WCA of 160.43° and OCA of 153.43°. Moreover, although cracked into powders with particle size of 0.1 mm, aerogel sample still retained its liquid-repellency with WCA of 122.85° and OCA of 128.01°, respectively. After thermal treatment under 200 ℃ for 2 h, the aerogel sample had WCA of 152.45° and OCA of 135.67°, showing excellent thermal stability. Taking advantage of low thermal conductivity and superamphiphobic properties, superamphiphobic aerogel has potential for fabricating self-cleaning and thermal insulating materials. [Display omitted] • In-situ fabrication of superamphiphobic aerogel by MTMS and fluoroalkysliane. • The unique three-dimensional networks yield superamphiphobic property. • Aerogel powders maintain liquid-repellency. • As-prepared aerogel has good thermal stability. [ABSTRACT FROM AUTHOR]

According to the World Health Organization, between 17% and 20% of water pollution is caused by dye treatments in the textile industry, which makes the development of efficient technologies for its removal essential. Environmentally friendly adsorbent materials, such as aerogels, can be effectively used in adsorption processes involving water remediation because of their high specific surface area and the possibility of an easy separation from the contaminated solutions. In this work, aerogels were obtained by a simple procedure that includes the cross-linking of chitosan with glutaraldehyde, followed by a freeze-drying step to eliminate water by water sublimation. The obtained aerogels presented low density (0.049–0.083 g/cm3), a three-dimensional skeletal structure that provides them with high porosity, acceptable swelling capacity and good dimensional stability. FTIR and X-Ray analysis were used to identify aerogels' chemical structure and dynamic-mechanical analysis to complement the characterization of these materials. Selected formulations were also tested as adsorbents of Congo Red in aqueous media. The adsorption results demonstrated that the aerogels adsorption capacity strongly depended not only on the crosslinking agent content but also on the amount of chitosan in the initial solution used in their synthesis. Moreover, preliminary thermodynamic studies of the adsorption process indicate that both adsorption rate and aerogel sorption capacity increase with increasing temperature. [Display omitted] • Chitosan/glutaraldehyde-based aerogels were successfully obtained by lyophilization; • Obtained aerogels presented very low density values that depend on their composition; • Aerogels adsorption capacity depended strongly on the amount of chitosan used in their synthesis; • Both electrostatic interactions and chemisorption influenced the Congo red adsorption process. [ABSTRACT FROM AUTHOR]

Polybenzoxazine aerogels have gained much attention as a new type of polymeric aerogels in the field of flame resistant materials. Herein, a unique method for the preparation of fiber-reinforced PBa composite aerogels has been reported using polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) as dispersion carriers through freeze-drying for surface modified basalt fibers (Z@BF). Bisphenol-A type benzoxazine (Ba) monomer was used as the matrix, which infiltrated into the carrier for dispersed fibers to obtain a PBa composite gel by sol-gel method. Solvent exchange and ambient drying techniques were used to obtain the final composite aerogel samples. Z@BF formed a double-network structure with the aerogel matrix, which resulted in 55.43% increase in compressive strength, a low volumetric shrinkage (27.46%), and density (0.19–0.21 g cm 3) of the prepared aerogel. The addition of Z@BF increased the residual carbon content (59.6% at 800 °C) in the aerogel, while reducing the total heat release rate by 36.9% and the peak heat release rate by 60.61%. Besides, the aerogels possessed excellent self-extinguishing property, and the self-extinguishing time was only 1.31 s after flame burning at 1200 ℃ for 10 s. The composite aerogels obtained by this combination of atmospheric pressure drying and freeze-drying techniques not only possessed high mechanical strength and excellent flame retardant properties, but also provided a new idea for the preparation of fiber-reinforced PBa aerogels. This would further expand the potential use of PBa aerogels in flame retardant materials. [Display omitted] • A polybenzoxazine composite aerogels system capable of effectively dispersing fibers with flame retardant properties is designed. • Basalt fibers enhanced mechanical and flame retardant properties of polybenzoxazine composite aerogels are realized. • The polybenzoxazine composite aerogels have excellent self-extinguishing properties and low combustion shrinkage upon flame ignition (1200°C). • The polybenzoxazine composite aerogels have a low peak heat release rate of 115.5 kW/m2. [ABSTRACT FROM AUTHOR]

La doped silica aerogel composites (La 2 O 3 /SiO 2 -n) with different Si/La molar ratio were synthesized through sol-gel method and atmospheric drying technology, which were used to adsorb thiophenic compounds from model fuels. Compared with the pure SiO 2 aerogel, the adsorption capacities of La 2 O 3 /SiO 2 -n obviously increased, owing to adding La species led to the appearance of the weak Lewis acid sites on the surface. The adsorption mechanism of La 2 O 3 /SiO 2 -n for thiophenics included the direct S-La bond and weak π-La acid-base interaction between La3+ and thiophenics, and the former was primary. Among La 2 O 3 /SiO 2 -n, the La 2 O 3 /SiO 2 -200 not only had the highest adsorption capacity for thiophene, up to 8.16 mg S/g ads (i.e., 138.31 mg-S/mmol La), but also exhibited an excellent anti-aromatics competitive adsorption ability and a good regeneration performance. The adsorption kinetic and adsorption isotherms were well described by pseudo-second-order (PSO) and Langmuir models, respectively, indicating the adsorption of La 2 O 3 /SiO 2 -200 for TH was dominated by chemisorption, which was a spontaneous and endothermic process. The present of aromatics in model fuels had a slightly negative effect on the adsorption of La 2 O 3 /SiO 2 for thiophene. [Display omitted] • Simple preparation of La 2 O 3 /SiO 2 aerogel composites. • Appearance of weak Lewis acid centers on the surface of aerogel after doping La. • The selective adsorption of La 2 O 3 /SiO 2 for thiophenics rather than aromatics. • The main adsorption mechanism was S-La bond instead of π-La acid-base interaction. [ABSTRACT FROM AUTHOR]

Aerogels (AGs) are porous materials with unique properties such as high specific surface area and low density, which makes them suitable for many applications in various medical, food and environmental sectors. At present, various types of AGs are being developed on a laboratory scale, with some even progressing to the pilot plant stage of development. The purpose of this review is to gather recent information from the literature on the classification, characterization, production and some applications of AGs in tissue engineering (TE), drug delivery, enzyme immobilization, food packaging, and pollutant removal sectors. [Display omitted] [ABSTRACT FROM AUTHOR]

Frequent oil spills have caused severe environmental pollution and ecological issues. Conventional adsorption materials are attractive candidates for oil spills, but their effectiveness is hindered primarily by certain high-viscosity oils. In this work, we fabricated a bio-based aerogel which is composed of sodium alginate and polyaniline-modified attapulgite, with photothermal conversion and water repellency (water contact angle > 138°) via freeze-drying and hydrophobic modification with polydimethylsiloxane. The composite aerogel has strong chemical stability, with a maximum absorption capacity of 32 g/g. Furthermore, the aerogel exhibits exceptional photothermal performance, achieving a surface temperature increase to 85 °C within 3 min under 1.0 sun irradiation. This capability reduces silicone oil absorption time from 4 to 1 min, conserving 75% of absorption time and reaching a silicone oil absorption capacity of 21 g/g. The separation efficiency of the aerogel for emulsions is also satisfactory, which greatly broadens its application range. The preparation of solar heated aerogels provides a potential solution for exploring biomass materials to solve the problem of oil spill recovery on a large scale. [Display omitted] • Bio-based aerogel with high hydrophobicity and photothermal performance is created. • ATP modified by PANI is used as the reinforcing material for SA aerogel. • A desirable absorption capacity of oil and organic solvents is presented. • The absorption of highly viscous oil is facilitated by solar-thermal conversion. [ABSTRACT FROM AUTHOR]

Using fly ash acid leaching residue as the silicon source, sodium silicate solution was produced by alkali leaching and the wet gel was obtained by the sol-gel method. Hexamethyldisiloxane (HMDSO) was used to modify the surface of the wet gel, thereby reducing the capillary tension during the atmospheric pressure drying process, and finally preparing a silica aerogel material with hydrophobic properties. The effects of different alkali leaching conditions, different sol pH, HMDSO dosage on the aerogel density and the changes of aerogel material properties and composition during the preparation process were investigated, and the reaction mechanism of silica aerogel preparation by atmospheric pressure drying was described. The results showed that the optimum conditions for alkali leaching were 20 wt% NaOH concentration, 2 h reaction time and 100 °C, and the desilication rate was 81.72%; the lowest Silica aerogel density of 108 mg/cm3 at pH 5 to 6; the lowest density of silica aerogel was 110 mg/cm3 at a modifier to wet gel volume ratio of 1:1.4. [Display omitted] [ABSTRACT FROM AUTHOR]

Polybenzoxazine/Melamine (PBa/MS) double network aerogels were prepared using melamine foam (MS) as the backbone and bisphenol A-type benzoxazine (Ba) as the maxtrix. The effect of Ba concentration in the sol-gel on the performance of the double network aerogel was investigated. During the combustion, the PBa/MS composite aerogel exhibited self-extinguishing performance. Compared with PBa-18%, the contact angle of PBa-18%/MS composite aerogel was 18° higher, and the heat release peak (PHRR) and total smoke production (TSP) of the composite aerogel decreased by 7% and 39%, respectively. These values indicate that MS can significantly reduce the release of heat and smoke from the PBa aerogel, thus improving its flame retardancy. In addition, the composite aerogel formed a denser and more complete carbon layer during combustion, which blocks both heat and mass transfer. Thus, the resulting PBa/MS dual-network composite aerogels obtained in the current work are expected to meet the demands for flame-retardant, hydrophobic thermal insulation materials in many fields. [Display omitted] • Benzoxazine/melamine composite aerogel has a double network structure. • Aerogels was prepared through drying at normal temperature and pressure. • Aerogel owned the properties of flame retardancy, smoke suppression, resilience, heat insulation and hydrophobic properties. • The composite aerogel has good thermal insulation at 200 ℃. [ABSTRACT FROM AUTHOR]

Polymer composite aerogel holds great promise for sewage treatment. Here, a novel triply crosslinked alginate/graphene aerogel for efficient organic dye removal was reported. The triple crosslinking of aerogel was realized firstly by the association between in-situ released Ca2+ ions and sodium alginate (SA). And the electrostatic attraction between polyethyleneimine-modified reduced graphene oxide (PEI-RGO) and the alginate chain provides an additional boost to crosslinking the aerogel. Moreover, the hydrogen bonding between PEI and SA also helps in achieving the crosslinking of the aerogel. Thus, the robust triply crosslinked alginate/graphene aerogel was obtained with using cost-effective precursors and a straightforward process. Additionally, the as-prepared aerogels were employed to remove the cationic dyes from wastewater. It was found that the porous alginate/graphene exhibited a strong affinity to methylene blue (MB) and neutral red (NR). The adsorption process of the aerogel towards MB was in accordance with the Langmuir isothermal model and pseudo-second-order model, and the maximum theoretical adsorption capacities were 1091.9 and 813.2 mg g−1, suggesting its potential application in sewage treatment. [Display omitted] • A multi-crosslinked alginate/modified graphene aerogel was developed. • The aerogel exhibits enhanced removal efficiencies toward MB and NR. • The adsorption kinetics and adsorption isotherms were studied in details. • The maximum adsorption capacities of MB and NR were 1091.9 and 813.2 mg g−1, respectively. [ABSTRACT FROM AUTHOR]

With acrylamide (AM), diethylenetriaminepentaacetic acid (DTPA), chitosan (CS), and graphene oxide (GO) as the raw materials, a GO-based composite aerogel named as APAM/DTPA-CS/GO (APAM = Anionic polyacrylamide) was constructed by a facile method. The composite aerogel was systematically characterized by scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction to confirm the successful preparation. Methylene blue (MB) was used as the model dye molecule to evaluate the adsorption behaviors of APAM/DTPA-CS/GO. The results showed that equilibrium adsorption capacity of the aerogel toward MB could attain 652.99 mg/g at 303 K, which was more efficient than many previously reported adsorbents. The main driving forces of adsorption process were electrostatic interaction, hydrogen bond, and π-π conjugate interaction. The adsorption process of MB by the composite aerogel could be well described by pseudo-second-order kinetic model and Langmuir isothermal model. APAM/DTPA-CS/GO still maintained high equilibrium adsorption capacity of more than 600 mg/g toward MB even after six adsorption-desorption cycles, indicating that the aerogel had excellent regenerability. The efficient and recyclable adsorption performances might endow GO-based composite aerogel with considerable application prospect in the treatment of dye wastewater. [Display omitted] • APAM/DTPA-CS/GO composite aerogel was fabricated by a facile method. • Equilibrium adsorption capacity of the aerogel toward MB was 652.99 mg/g at 303 K. • The aerogel exhibited efficient and recyclable adsorption performance for MB. [ABSTRACT FROM AUTHOR]

In this work, porous phenol formaldehyde carbon aerogel (PFCA) was facilely manufactured by using simple hydrothermal method and ambient pressure drying. The micromorphology, specific area and electrochemical characteristic of the produced carbon aerogel were examined with scanning electron microscopy, nitrogen adsorption-desorption tests, cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The effects of catalyst and phenol addition, and solvent type on the structure and property have been systematically studied. The results show that the PFCA has a three-dimensional "bead chain" network structure and the typical PFCA-7.5/8 sample exhibits high specific surface area of 759.02 m2 g−1. Moreover, the graphene oxide composited phenol formaldehyde carbon aerogel (GO/PFCA) presenting a lamellar structure was developed by using GO as template. The optimum PFCA-7.5/8 prepared with ethanol as solvent has the best electrochemical performance of 138.33 F g−1 at 5 mV s−1 in 6 M KOH electrolyte, which can be improved to 150.00 F g−1 for the GO/PFCA-3 sample. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing adsorbent materials based on biomass that can be easily recycled and reused to remove water pollutants has received widespread attention. A novel method for the preparation of calcium alginate/poly (vinyl alcohol)/boric acid (as–synthesized Ca-APB) aerogel fibers for highly efficient adsorption of methylene blue by directed freezing wet–spinning was presented in this paper. The Ca-APB-0.5 aerogel fibers exhibited a hierarchical structure consisting of a honeycomb micron pore structure with mesopores walls, with a maximum adsorption capacity of 508.99 mg/g in 5 h at 293 K. Meanwhile, the experimental data for Ca-APB-0.5 aerogel fibers showed the best fit to the Freundlich model and pseudo–second–order model. Moreover, the adsorption capacity was investigated for three consecutive cycles, with 469.37, 457.19, and 439.77 mg/g in the first, second, and third cycles, respectively. This paper proves that the hierarchical structure of alginate-based aerogel fiber is an effective dye adsorption material with high efficiency, reusability, and eco-friendliness. [Display omitted] • Robust alginate–based aerogel fibers via directed freezing–wet spinning. • Restriction of Ca2+ complexation by boric acid reduces the consumption of active groups. • Efficient adsorbent based on multi-active groups and hierarchical structure. • Micron macropores for channeling and nanopores for adsorption, inspired by soil pores. • Aerogel fibers realized high efficiency, reusability, and eco-friendliness. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation (SIE) and desalination is a promising approach to mitigate the scarcity of freshwater resources. Here, a three-dimensional polypyrrole (3D PPy) aerogel was prepared by in situ polymerization of pyrrole to serve as an independent evaporator. The interconnected pore structure and super-hydrophilicity enabled PPy evaporators with rapid water transport to the top interface (< 5 s). The hydrogen interaction between polymer chains and water molecules induced large amount of intermediate water, thereby reducing the evaporation enthalpy of water in PPy aerogels. As a result, the optimized PPy aerogel attained an evaporation rate of 2.90 kg m−2 h−1 and an energy conversion efficiency of 114% under 1 sun irradiation. Moreover, the generated steam can be accelerated by the convection and an evaporation rate as high as 6.10 kg m−2 h−1 was realized at 2.5 m s−1. The rapid water transport also enabled PPy aerogel with high-efficiency of self-salt-discharge and efficient desalination for 3.5 wt% brine under 2.5 m s−1. In the outdoor SIE experiment, the excellent evaporation performance was achieved at 12:40 (7.04 kg m−2 h−1 under 74.2 mW cm−2 of solar intensity and 2.5 m s−1 of convective flow), and the cumulative evaporation of 41.50 kg m−2 for successive 9 h was obtained. After the evaporation of simulated seawater and heavy metal wastewater, the concentration of collected fresh water could be reduced about 2–3 orders of magnitude. This 3D PPy evaporation platform with high light absorption, porous structure, super-hydrophilic property, effective steam diffusion, and excellent salt resistance provides an effective way to develop advanced solar-driven water treatment technology. [Display omitted] • 3D PPy aerogel was prepared by in-situ polymerization of pyrrole. • PPy had synergy of energy conversion, porous structure, and super-hydrophilicity. • The evaporation rate was 6.1 kg m−2 h−1 under 1 sun and 2.5 m s−1 of convection. • The maximum evaporation rate was 7.04 kg m−2 h−1 in outdoor desalination system. • Efficient desalination and salt-resistance capacities of PPy aerogel were achieved. [ABSTRACT FROM AUTHOR]

Methyl orange (MO), which is known as a highly durable dye that is extremely toxic to humans and animals, has been processed by using various methods. In recent years, MO degradation through reduction in the presence of NaBH 4 (NB) and suitable nanocatalyst have garnered considerable interest. However, the nanosized particles of the catalyst make separation from the liquid solution more difficult and limit the practical application of this technique. Herein, copper nanoparticles (CuNPs) decorated on three-dimensional chitosan aerogel (CSA) were synthesized as a reusable composite for the catalytic degradation of MO by using a green method with durian (Durio zibethinus) shell (DS) extract as a reducing agent. The Cu/CSA composite's physicochemical properties were characterized by using X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy- energy dispersive X-ray spectroscopy (SEM-EDS), high resolution Transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) and Raman spectroscopy. These modern techniques elucidated the structure and formation of copper nanoparticles on the CSA surface. The copper nanocatalysts have an average particle size of 32.6 nm, specific surface area of 55.8 m2/g, pore size of 32 Å and pore area of 0.049 cm3/g. Through the investigation of catalyst activity, the conditions of MO reduction were optimised with the 1.0 Cu/CSA sample, catalyst dose of 0.5 g/L and a molar ratio of MO/NB of 1/200. The reaction reached over 94.3% efficiency after 10 min, correlating with a kinetic rate constant of 0.163 min−1. It is worth mentioning that the optimized catalyst can be conveniently synthesized and retrieved from the reaction solution in just 5 s using a vacuum filter. Furthermore, its effectiveness remains largely unaffected even after undergoing five cycles of reuse, thus demonstrating its exceptional durability and potential in environmental remediation. [Display omitted] • An alternative chitosan aerogel-based support for metal nanoparticles. • Nano-copper/chitosan aerogel (Cu/CSA): a benign reduction using durian shell extract. • Outstanding reactivity of Cu/CSA in the catalytic reduction of methyl orange. • High stability and proficient reusability of Cu/CSA during 5 consecutive cycles. [ABSTRACT FROM AUTHOR]

• Recycled fibers from car tire waste developed successfully into rubber aerogels • Aerogels have low density, highly porous but are much stiffer than Styrofoam • MTMS coating converts completely their hydrophobicity to super hydrophobicity • Excellent sound adsorption, high flexibility and low thermal conductivity • Versatile rubber aerogels are for several high-value engineering applications For the first time, recycled car tire fibers (RCTF) shredded from car tire waste are developed successfully into a novel material, a rubber aerogel, using polyvinyl alcohol (PVA) and glutaraldehyde (GA) as crosslinkers through a cost-effective freeze-drying method. Its structure and main physical properties are investigated comprehensively for high-value applications, such as heat and sound insulation of buildings and oil spill spilling clean up. The rubber aerogel has ultra-low density (ρ a = 0.035 – 0.145 g/cm3) and high porosity (Φ avg = 84.31–96.20 %). With a simple but effective coating method with methoxytrimethylsilane (MTMS), both the interior and exterior of the whole rubber aerogel surface can be well coated, and the coated aerogel exhibits a super-hydrophobicity with a water contact angle of up to 134.4°. The rubber aerogel exhibits excellent heat insulation properties (K avg = 0.035 – 0.047 W/m.K), very good thermal stability up to 500 °C, and significantly-enhanced rigidity up to a Young modulus of E avg = 458.12 kPa, much larger than that of commercial Styrofoam. The rubber aerogel shows very good durability as it springs back to its original shape after compression tests. The rubber aerogel has a noise reduction coefficient (NRC) of 0.41 and performs approximately 10% better than commercial sound foam absorber at 2000–3000 Hz. The maximum oil absorbtion capacity of the rubber aerogel in this work is 19.3 g/g, very competitive to commercial sorbents. The fabrication method can also be scaled up for several other industrial applications, not limited to sound, heat and sorbent applications. [ABSTRACT FROM AUTHOR]

Efficient adjusting of reduced graphene oxide aerogels properties requires information about experimental factor-aerogel property relationship. In this work, the reduced graphene oxide aerogels surface and textural functionalities in relation to precursor concentration, gelation time and hydrogel freezing temperature were studied in detail, with the use of dynamic adsorption method of gaseous organic probes and experimental design. The precursor concentration and the hydrogel freezing temperature have the strongest influence on textural properties - a negative correlation with apparent surface area was observed. The highest value of 229.36 m2 g−1 was obtained for samples synthesized at the lowest concentration of precursor (2 mg mL−1) and hydrogel freezing temperature (−196 °C). Low precursor concentration promote formation of more hydrophobic aerogels. All aerogels display tendencies for dispersive, dipole-type and electron donor interactions. Moreover, a repulsion of electron lone pairs was observed, as well as shape-based selectivity (originating from porosity and surface roughness) in gas-solid adsorption process. Analysis of the free surface energy revealed that the maximum value (193.21 mJ m−2) is obtained at 7.2 mg mL−1 precursor concentration, − 104 °C hydrogel freezing temperature and 23 h gelation time. Presented findings can translate directly into reduced graphene oxide aerogels tailored for specific applications such as adsorption or catalysis. [Display omitted] • Step forward in properties control and "tailored" rGOAs engineering. • Free surface energy depends only on GO dispersion concentration for rGOAs synthesis. • Highest aerogels hydrophobicity is promoted by low GO dispersion concentration. • Higher freezing temp. of hydrogel promote aerogels with lower surface area. • Increased aerogel's surface roughness obtained in higher freezing temp. of hydrogel. [ABSTRACT FROM AUTHOR]

Liquid-filled porous membranes have been developed for oil-water separation with antifouling properties. However, the degradation of fouling resistance and reduction of separation efficiency may occur due to the poor stability of the liquid layer. Prompted by the mesoporous structure and high porosity characteristics of aerogel, the membrane with aerogel-network-stabilized slippery surfaces was fabricated by in situ growth of silica aerogel coating on the polyethylene terephthalate (PET) fiber membrane and silicone oil filling. Owing to the oil-locking ability of the aerogel coating, the liquid layer of the membrane showed excellent stability against chemical corrosion and high-temperature, improved stability against shear and mechanical abrasion, and good hot water tolerance and self-healing performance. The prepared liquid-filled membrane can efficiently separate water-in-oil emulsion. In filtrating-cleaning cycles, the membrane showed antifouling property and durability with high separation efficiency and flux recovery. The membranes with highly stable liquid-filled surface provide promising prospects in industrial oil treatment and oil spill recovery. [Display omitted] • A nanoporous aerogel coating is prepared on membrane surface to lock the filled liquid. • The liquid layer of the membrane is highly stable under harsh conditions. • Liquid-filled membrane has high separation efficiency and durable antifouling property. [ABSTRACT FROM AUTHOR]

Dimethyl-diethoxysilane-modified ZrO 2 -SiO 2 aerogels (DDS/ZSAs) have been prepared by using diethoxydimethylsilane as a co-precursor in the sol-gel process. Dimethyldiethoxysilane acts as a modifier for the three-dimensional structure and composition of aerogels. The pore volume increased from 1.65 cm3/g to 3.21 cm3/g, and the thermal conductivity decreased from 0.03013 Wm−1K−1 to 0.02332 Wm−1K−1 at room temperature. The number of hydroxyl groups on the aerogel surface is effectively reduced, and the particle growth caused by hydroxyl condensation was inhibited during firing. The increase in the number of Si-O-Zr bonds inhibited the growth of t-ZrO 2 , the phase transition temperature of the aerogel was significantly improved, and the crystallinity and crystal plane types were significantly reduced. Therefore, the porous microstructure of the modified aerogel remains good at 1000 °C. After heat treatment at 1000 °C, it still has a high specific surface area (259.6 m2/g), a high pore volume (1.51 cm3/g), and a low thermal conductivity (0.04206 Wm−1K−1). The thermal insulation performance and temperature resistance of ZrO 2 -SiO 2 aerogels were double improved. In addition, DDS/ZSAs have high hydrophobicity and can be used in harsh wet and high-temperature environments. The research work is instructive for the design of superthermal insulation materials with high thermal stability and low thermal conductivity. [Display omitted] • Preparation of dimethyldiethoxysilane modified ZrO 2 -SiO 2 aerogels. • Composition and structure of the three-dimensional network of aerogels optimized. • Double improvement of thermal insulation and temperature resistance of aerogels. • Ultra-low thermal conductivity at room temperature (0.02332 Wm−1K−1) and after 1000 °C burning (0.04206 Wm−1K−1). • Materials can be used in both harsh humid and hot environments. [ABSTRACT FROM AUTHOR]

Nanostructured materials with designable microstructure fabricated through a facile and green method are highly desired for practical applications in nanotechnology. Herein, without using any toxic reagents, flexible cellulose aerogel nanocomposites embedded with ZnO@noble metal nanoparticles (NPs) were successfully prepared from a cellulose dope. Morphology, structure, and mechanical properties of the nanocomposite were characterized. Flower-liker ZnO particles were synthesized through cellulose mineralization and it acted as a platform for efficient photocatalytic synthesis of noble metal (Ag, Au, Ag-Au) NPs. The noble metal NPs were well dispersed in the three-dimensional (3D) cellulose skeleton, resulting in abundant "hot spots" for high Surface Enhanced Raman Scattering (SERS) signal enhancement. Using rhodamine 6 G (R6G) molecules as probe molecules, the detection limits and calculated enhancement factors approached to 10−10 M and 4.8 × 107, respectively. Particularly, the photocatalytic capabilities of noble metal-semiconductor heterostructure embedded in porous aerogel made it a self-cleaned SERS substrate. There was little sensitivity loss after recycling use for 3 times. This work presented a sustainable and cost-reduction strategy to construct sensitive SERS substrate. [Display omitted] • Cellulose aerogel embedded with ZnO@Ag/Au is facilely fabricated from a dope. • The actived celluloe chains act as mineralization template for flower-like ZnO. • Ag/Au NPs are plated to ZnO surface through a controllable photoreduction method. • 3D porous aerogel gives anchoring effect for particles and bring abundant "hot spots". • Hierarchical nanostructures achieves a flexible, sensitive and reusable SERS strips. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Aerogel micro-particles have a wide range of applications demonstrated at lab-scale in numerous publications, but material in a larger amount needs to be produced to allow for industrial tests and prototyping. In this work, we propose a continuous emulsion-gelation process able to produce gel micro-particles in sizeable quantities, demonstrating the industrial relevance of such approach. Alginate is taken as a model gelling system and two gelation mechanisms are demonstrated. Alginate solution and oil are pumped together through a progressive cavity pump and fed to a colloid mill to produce alginate in oil emulsion in one pass. The gelation in emulsion is then carried in-line via a controlled injection of a gelation trigger (acetic acid or calcium chloride). The gel microparticles are separated from the oil via sedimentation or centrifugation and partitioning into an ethanol solution. Further solvent exchange to ethanol and supercritical drying with CO 2 yielded aerogel microparticles with large specific surface area. The size of the emulsion droplets is directly related to the final aerogel particles size. The influence of the emulsification parameters on the droplet size is thus discussed and assessed using critical capillary number values from the literature. To complete this task, the dynamic interfacial tension of the alginate-paraffin oil-Span80 system was measured and the rheology of the alginate solution and of the emulsion assessed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • rPET-silica aerogels are successfully developed from plastic bottle waste. • Ultra-low thermal conductivity and high thermal stability. • Very low compressive Young’s Modulus and very soft. • Fabrication method can be scaled up for industrial applications. Abstract Recycled polyethylene tetraphalate (rPET) fiber–silica aerogels are successfully developed from rPET fibers obtained from PET plastic bottle waste and tetraethoxysilane (TEOS). The rPET – silica aerogels are prepared through a direct gelation of silica on PET. rPET fibers are treated with dichloromethane to partially dissolve the fibers. The fibers are then dipped and allow to swell in TEOS/ethanol mixture, with the pH controlled to 2.5 using HCl to promote hydrolysis. After the acid hydrolysis, the pH was controlled to 7 with an ammonium hydroxide solution (NH 4 OH) to promote condensation. The surface modification is carried out in a trimethylchlorosilane (TMCS)/n-hexane solution and washed with n-hexane to dry at room temperature to prevent shrinkage. The developed rPET – silica aerogels exhibit super-hydrophobicity with an average water contact angle of 149.9°. Their thermal conductivity is approximately 0.037 W/m K. They have a very low compressive Young’s Modulus (0.95–4.19 kPa) and hence very soft. By utilizing rPET fibers, this work provides an alternative method of recycling PET plastic wastes which ultimately helps in reducing its detrimental impact to the environment. The developed aerogels can be used in several industrial applications such as heat insulation, filtering, sound insulation and absorption. [ABSTRACT FROM AUTHOR]

Graphical abstract A new type of highly recyclable cellulose aerogels with ultrahigh selective and efficient adsorption capacity for anionic dyes has been facilely synthesized for the decontamination in both batch and continuous fixed-bed systems. Abstract A new type of polyethylenimine modified cellulose (PMC) aerogels were synthesized through a chemical cross-linking process, by which plenty of amine groups were introduced to the surface of cellulose aerogels. FT-IR, SEM, EDS, BET and XPS were used to characterize the physicochemical properties of this novel composite. The prepared aerogels were used to remove anionic dyes from effluents and it exhibited excellent adsorption performance in batch and fixed-bed experiments. Adsorption results indicated that PMC could efficiently, selectively separate anionic dyes from dye mixtures and maintain the maximum absorption capacity even after ten regeneration cycles, exhibiting superior selectivity and desirable recyclability. The maximum adsorption capacities of PMC for rose bengal and methyl blue were 1310.21 and 1333.04 mg/g, respectively, which were much higher than those of previously reported results. The Kinetics and isothermal adsorption data were well described by pseudo-second-order kinetic model and Langmuir model. The breakthrough curves obtained from fixed-bed systems were well fitted by Thomas model. Most importantly, anionic dyes could be efficiently removed even with high concentrations of coexisting anions. All these results manifested that PMC could be a promising candidate for sewage treatment, profiting from the fascinating merits of easy separation, low-cost, high adsorption capacity, strong anti-environment disturbance, superior reusability and selectivity. [ABSTRACT FROM AUTHOR]

Carbon aerogel prepared using waste biomass as the carbon source can be utilized as the ideal absorption material for the remediation of oil spill accidents. However, the brittleness of the fiber and agglomeration of precursor fiber chains due to hydrogen bonding leads to poor mechanical properties and low absorption capacity of the carbon aerogel. The doping treatment used to overcome such defects still shows some deficiencies, such as high cost, cumbersome process, and part of the process involving toxicity. To overcome the agglomeration between the cellulose chains, a chemically-etched biomass-based carbon aerogel (EBCA) was prepared using pineapple cellulose nanofiber (CNF) etched by the deep eutectic solvents (DES) of choline chloride/urea under a low carbonization temperature of 400 °C. The as-prepared material, designated as EBCA-400, possesses a 3D structure with a huge BET specific surface area of 501.56 m2 g−1, a density of only 0.032 g cm−3 and a porosity of 97.3% with excellent elasticity performance and self-recovery performance owing to the enhancement of the surface roughness of fibers through DES etching. Also, EBCA-400 shows a superhydrophobicity with a water contact angle (WCA) of 157.6° and has a strong and fast absorption capacity for various oils in various scenarios, the absorption capacity for CCl 4 reaches 288 times its own weight, and the absorption efficiency to CCl 4 can still reach more than 97% of the maximum value even after 15 oil absorption-removal cycles. With the characteristics of very low density, huge porosity, excellent elasticity and superhydrophobicity as well as better reusability, EBCA-400 has great potential in oil spill remediation. This study provides a convenient and environment-friendly way for surface modification to improve the elasticity of carbon aerogel, which is crucial to the recovery of carbon aerogel for its reusability. [Display omitted] • EBCA-400 was prepared at a lower carbonization temperature. • Chemical etching imparts EBCA-400 excellent elasticity. • EBCA-400 possesses superhydrophobicity with WCA as high as 157.6°. • EBCA-400 shows excellent absorbency to various oils and reusability. [ABSTRACT FROM AUTHOR]

The Gum Ghatti (GG)/Konjac Glucomannan (KGM)/zeolitic imidazolate framework-8 (ZIF-8) composite aerogels (GKZ) were synthesized by the sol-gel method and the vacuum freeze-drying method for effective removal of ciprofloxacin (CIP) from contaminated water. The results showed that the addition of different concentrations (0, 0.4, 0.6, 0.8 wt%) of GG could promote homogeneity but weakened the molecular interaction of the aerogel system without water. Remarkably, the ZIF-8 maintained the crystal structure, as well as its dispersion on the surface of aerogel, was significantly improved. Additionally, it was also found that the incorporation of moderate GG was favored regarding CIP adsorption, and GKZ with 0.6 % GG (GKZ0.6) exhibited the highest adsorption capability for CIP around 1035.4 mg/g. Besides, the effects of various ions, ionic strength, and pH on CIP adsorption were also investigated, which provided the reference for guiding the utilization of GKZ0.6. Furthermore, at fewer cycles, the adsorption efficiency of GKZ0.6 on CIP showed less loss. These features revealed that the GKZ composite aerogels might be a promising adsorbent for CIP removal from water. [Display omitted] • Gum Ghatti/Konjac Glucomannan/Zif-8 Composite Aerogel (GKZ) presented a layered network structure. • Moderate Gum Ghatti promoted the adsorption capacity of GKZ for CIP. • pH= 7.0 was a favor for the CIP adsorption of GKZ0.6. • GKZ0.6 showed better repetitive absorption capacity on the CIP at fewer cycles. [ABSTRACT FROM AUTHOR]

This study reports on porous composites obtained from evaporating slurries based on silica aerogel (SA) and natural rubber latex (NRL) dispersed in cyclohexane and water respectively. The slurries are emulgels where droplets of NRL are entrapped in a dense suspension of SA. Confocal laser scanning microscopy reveals that the smallest silica particles organize around the latex droplets to form a steric layer consistent with a Pickering effect. Upon drying, the gel-like behavior of the slurry allows its structure maintain. The dispersive X-ray diffraction combined with scanning electronic microscopy hints that the pores are the footprint of the droplets but coated by the NRL that increasingly fills the interstices between the SA particles as the NRL concentrations increases. The elastic modulus G′ of the slurries shows a power law dependence on the SA concentration and found to be proportional to the product of the droplet size and the modulus of the SA suspension. The Young modulus of the porous composites varies as a scare route of G′ and highlights that the final mechanical features of the composite could be predicted from the viscoelastic properties and the structure of the slurry. [Display omitted] • SA/NRL-based slurries consists of NRL droplets dispersed in SA/cyclohexane phase in presence of a Pickering structure. • The morphology of SA/NRL-based composites show SA skeleton and NR cavity that correspond to the slurry's microstructure. • Young modulus of dried composite is proportional to the square root of the shear elastic modulus of the slurries. [ABSTRACT FROM AUTHOR]

Electrospun nanofiber membranes are frequently used in adsorption processes thanks to their high specific surface area, tailored surface functionality, and fiber uniformity. However, they are still facing challenges such as low mechanical stability and unfavorable mass transport properties. In this study, an ultra-light and robust 3D nanofiber aerogel (NFA) or nanofiber sponge with tunable porosity and flexibility was synthesized from short pullulan/polyvinyl alcohol/polyacrylic acid nanofibers using a freeze casting process followed by thermal crosslinking. We demonstrate time the application of such NFAs in batch and continuous adsorption systems and compare their performance with flat nanofiber membranes (NFM). The NFAs proved to be promising adsorbents for cationic dyes due to their high adsorption capacity (383 mg/g) and their reusability. Langmuir isotherm was a suitable model for describing the adsorption process. The endothermic system followed a pseudo second order kinetic model and intra-fiber adsorption is found to be involved in the adsorption process. Dye adsorption by 3D NFAs was four times faster than for the respective flat NFMs and when used in a continuous process as a deep-bed filter, the pressure drop through the NFA was reduced by a factor of 40 while maintaining equal adsorption performance as for the NFM. [ABSTRACT FROM AUTHOR]

KGM/ZIF-8 aerogels were synthesized by combining konjac glucomannan (KGM) with zeolitic imidazolate framework-8 (ZIF-8) for the removal of ciprofloxacin (CIP) from water. The structure, morphology and properties were studied by TEM, SEM, FTIR, XRD and XPS. The effects of pH, ionic strength, contact time and temperature were investigated. Rheological studies indicated that KGM/ZIF-8 hydrogels were pseudoplastic fluid, and KZ0.5 performed the best in terms of the plasticity. KZ0.5 showed excellent CIP adsorption performance. The adsorption kinetics followed the pseudo-second-order model, and CIP adsorption was fit well by the Langmuir model (R 2  > 0.99), which suggested the monolayer adsorption of CIP due to the uniform pore size distribution on the surface of KZ0.5.The maximum adsorption capacity of the KZ0.5 reached to 811.03 mg/g at 303 K when the concentration of CIP was 1500 mg/L (pH = 7.0), which was higher than that of the other adsorbents. Thermodynamic parameters, such as △G, △H and △S, were estimated to understand the mechanism of CIP adsorption. KZ0.5 showed no significant decrease in CIP adsorption after six cycles. These features reveal that KGM/ZIF-8 aerogels may be promising adsorbents for CIP removal from water. [ABSTRACT FROM AUTHOR]

A facile sol-gel route is developed to build mesoporous 3D NiCo 2 O 4 /MWCNT nanocomposite aerogels. The crystal structure, surface morphology and electrochemical performance of the aerogel composites are investigated by X-ray diffraction (XRD), Field-emission scanning electrochemical spectroscopy (FE-SEM) and electrochemical measurements. The effects of MWCNT concentration on the capacitance performance of MWCNT/NiCo 2 O 4 aerogels are studied. It is found that the NiCo 2 O 4 /MWCNT nanocomposite aerogels with MWCNTs ∼ 2.1 wt% reach the maximum specific capacitance of up to 1010 F g −1 at a discharge current density of 0.1 A g −1 with excellent cyclic stability. Further, these materials are applied for solid-state asymmetric supercapacitors and show higher areal capacitance value (471.8 mF cm −2 ) at a current density of 5 mA cm −2 with good cycle stability and glowing red LED for 3mins. The superior electrochemical performance is due to the mesoporous structure and well-connected metal nanoparticles with MWCNT in the nanocomposite aerogels, which can provide more active sites to enhance the electrochemical performance of the device. [ABSTRACT FROM AUTHOR]

Adsorbent 3-D sodium bisulfite reduced-graphene aerogels (S-rGA) were fabricated via the reduction of graphene oxide. It has high adsorption capacity and excellent reusability for the removal of tetrabromobisphenol A (TBBPA). S-rGA with its unique block and porous network structure was characterized using scanning Electron Microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis. The adsorption characteristics of S-rGA to TBBPA were investigated through batch experiments. In the study, the adsorption kinetics were well described by the pseudo-second-order model. The adsorption equilibrium well fit to the Langmuir model with maximum adsorption capacity of 128.37 mg/g. Thermodynamic parameters suggested that the adsorption of TBBPA was exothermic and spontaneous. Fourier transformed infrared (FTIR) spectra indicated that π π interaction might be consistent with the adsorption of TBBPA by S-rGA. Furthermore, reuse experiments indicated that S-rGA could be regenerated five times with only a slight loss in adsorption capacity. These results demonstrated that S-rGA is potentially an ideal adsorbents for enhancing the adsorption capacity of TBBPA in aqueous environments. [ABSTRACT FROM AUTHOR]

The present paper investigates the mixing temperature on the structure and performance of clay aerogel colloidal suspensions and their composites. Clay-polymer aerogels were prepared via an environmentally friendly freeze-drying technique and clay aerogel suspensions were subjected to various temperatures, namely room temperature (RT), 60, 70, 80 and 90 °C, in order to better understand the architecturing of clay colloidal suspension and formulation mechanisms of advanced clay aerogel composites, and such develop the optimum processing parameters. This research demonstrated that the mixing temperature had a significant influence on the chemical interaction of the constituents and formulation of bonding/networking of clay aerogel colloidal suspension, and hence the microstructure and performance of the clay aerogel composites; by simply controlling the mixing temperature without altering the composition or adding any additive or increasing the solid content, it was possible to significantly increase the compressive modulus by up to 7 folds without sacrificing any of the physical property of clay aerogel composites. [ABSTRACT FROM AUTHOR]

In this work we report the use of a nanoporous layer of TiO 2 aerogel as an electron-transport layer in CH 3 NH 3 PbI 3 -based solar cells. Due to its high surface area, the modified TiO 2 aerogel increases the contact surface, enabling the deposition of a higher concentration of perovskite, and enhances the layer interpenetration process. In order to avoid short circuit by the presence of pinholes in the aerogel layer, a thin film of TiO 2 paste was also deposited. The TiO 2 aerogel layer promoted an incident photon to current efficiency (IPCE) twice as large when compared to the IPCE in solar cells without the aerogel layer. This result shows that aerogel based inks are quite promising for use in high-performance perovskite solar cells (PSCs). [ABSTRACT FROM AUTHOR]

Facing the increasingly serious water pollution problem, photocatalytic method has been recognized as one of the best solutions due to its convenience, efficiency and low consumption. Graphitic carbon nitride (g-C 3 N 4), a metal-free and visible light-responsive photocatalyst, has shown great potential in the photocatalytic treatment of water pollution. This study describes a novel bottom-up strategy for constructing visible light-responsive photoactive nanocomposite g-C 3 N 4 /CNC/PAM aerogel with the g-C 3 N 4 uniformly loaded throughout a polymeric network, perfect mechanical property and high performance in treating wastewater containing organic/heavy metal compound contaminants. Aldehyde-modified negatively charged natural nanoparticle cellulose nanocrystal (CNC-CHO) was used to achieve uniform dispersion of g-C 3 N 4 , and also participate in the subsequent formation of aerogel through chemical crosslinking with photoinitiated polyacrylamide (PAM) catalyzed by g-C 3 N 4 without additional crosslinkers. The optimized porous structure of the prepared aerogel ensured high swelling rate of up to 2500%, excellent pollutant adsorption performance and high light transmittance, thus achieved high removal rate and removal efficiency for different types of pollutants including organic dyes (RhB, MB and CR) and heavy metal Cr(VI). The removal efficiency could get 99% for RhB (5 mg/L) in 6 h, and 95% for Cr (VI) (10 mg/L) in 100 min under visible light. Further more, the aerogel showed excellent mechanical stability and reusability, with no loss in activity observed after over 5 cycles of dye degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

Developing advanced electrode materials for sodium ion batteries (SIBs) to meet the urgent need of high performance is still challenging. In this study, a novel SIBs negative electrode composite material (N/(Ni, Co)Se 2 NFCs@RGOA) was prepared by loading N-doped bimetal derived nano-framework cubes (N/(Ni, Co)Se 2 NFCs) on reduced graphene oxide aerogel (RGOA). The nano-size and hollow cage structure of N/(Ni, Co)Se 2 NFCs cooperate with the layered branched carbon skeleton and porous structure of RGOA to accelerate the reaction kinetics, therefore alleviate the structure collapse caused by volume expansion, and boost the conductivity of the material. The characterization and electrochemical testing results show that the electrode material has remarkable electrochemical performance (reversible capacity of 497 mA h g−1 at 0.1 A g−1), capacity stability (395 mA h g−1 after 200 cycles) and excellent rate performance (389 mA h g−1 at the current density of 2 A g−1). The as designed electrode material will play a significant role to benefit the development of SIBs and advanced electrical storage applications. [Display omitted] • A novel N-doped Ni-Co bimetallic derived electrode material was prepared. • N/(Ni, Co)Se 2 NFCs@RGOA has hollow nano-framework cubic and porous structures. • The reversible capacity of N/(Ni, Co)Se 2 NFCs@RGOA at 0.1 A g−1 is 497 mA h g−1. • Electrode material exhibits excellent rate performance and capacity stability in SIBs. [ABSTRACT FROM AUTHOR]

The ZIF-67 @PLA honeycomb aerogel was formulated by using the metal–organic frame (MOF) ZIF-67 through physical mixing and heat-induced phase separation interaction. Changing the mass fraction ratio of ZIF-67 in aerogels can effectively adjust the pore size, pore surface unevenness, and specific surface area of pure polylactic acid (PLA) aerogels. In comparison to PLA aerogels, the ZIF-67 @PLA honeycomb aerogels showed greater oil wettability combined with a notable increase in mechanical characteristics. In this paper, the morphology, oil adsorption capacity, oil wettability, oil–water separation ability and sample reuse of composite aerogels were studied in depth. The ZIF-67 @PLA aerogel with 3 wt% ZIF-67 has the highest oil wettability, highest oil–water separation function, maximum specific area and good reusability. Compared to pure PLA, which has a tensile strength and elongation at break of 0.1424 MPa and 13%, ZIF-67 @PLA has a tensile strength and elongation at break of 0.3344 MPa and 15%, respectively. After 20 cycles, the separation flux of ZIF-67 @PLA is still 98% of the initial flux. The experimental results show that the use of MOF as a nanofiller-filled pure PLA aerogel exhibits high oil wettability and has been demonstrated to be an ideal material for high-efficiency oil–water separation. [Display omitted] • Processing a high-hydrophobic aerogel with honeycomb structure for oil–water separation. • ZIF-67 significantly reduced the void size of the PLA aerogel. • The oil–water separation flux remained at the initial high level after 20 cycles. [ABSTRACT FROM AUTHOR]

Radioactive aerosols in confined spaces of workplaces are the main source of internal radiation hazards for staff. Therefore, biomass-based electret fiber materials as alternatives of petroleum-based polymers will be of great potential in capturing radioactive aerosols due to its biodegradability, renewability and electrostatic effects. Herein, a fabrication strategy of bamboo pulp-based electret fiber aerogels by corona polarization is reported grounded on p-phenylenediamine (PPD)-modified bamboo pulp fibers (BCFs) and ethyl cellulose (EC). The morphology, chemical structure, and physical properties of BCFs before and after modification, as well as the electret properties and purification performance of fiber aerogel were analyzed. The results showed that PPD can be grafted uniformly on the surface of BCFs, making the fibers transform from irregular cylindrical shape with hierarchical surface to regular cylindrical shape with smooth surface, and can improve the surface potential of the fibers, one of the considerably great electret properties, from 0.00 kV to 1.33 kV when the graft amount of PPD was 0.500 g/g. The improvement in surface potential, leading by the grafted PPD structure which is a charge-trapping site confirmed by stoichiometric calculations, enhance the electrostatic trapping effect of the fibers on radioactive aerosol particles and shorten the purification time from 26 min to 15 min. Moreover, the electret fiber aerogel with modified BCFs (named as PPD-DABCFs) has a low air resistance of 56 Pa at the flow speed of 5.3 cm·s−1, a light base weight of 62.7 g·m−2 and a long service life. Therefore, the bamboo pulp-based electret fiber aerogel has a promising application in the field of radioactive aerogel purification. [Display omitted] • BCFs-based electret instead of petroleum polymer electret can increase its environmental friendliness. • The electret fabrication base on biomass materials is a sustainable development strategy. • The electret fiber aerogel has an excellent charge storage ability, light base weight and low resistance. • The electret fiber aerogel with 3D pore structure can be stable for long term use. [ABSTRACT FROM AUTHOR]

The biodegradation of polycyclic aromatic hydrocarbons (PAHs) and monoaromatic hydrocarbons (MAHs), comprised in the petroleum, is slow and is associated with mutagenic, teratogenic and carcinogenic effects in humans. Aerogels are nanoporous, high surface area materials with easy recovery and high sorption capacities. In this work, the interaction between the aerogel-like material prepared with methyltrimethoxyslane (MTMS) and mix solutions containing MAHs ( e . g ., benzene, toluene and xylenes (BTXs)) and PAHs ( e . g ., pyrene, benzo(b)fluoranthene and benzo(a)pyrene) has been assessed. We found that the simultaneous sorption of all aromatic hydrocarbons occurs following a multilayer mechanism, highlighting the role of hydrophobic adsorbent-adsorbate and adsorbate-adsorbate interactions. We have also found that the removal efficiency is similar for all adsorbates and are equal to 16–18%, which leads to a total removal efficiency of around 100%. Desorption experiments show desorption efficiency of ca . 100% for PAHs; however, BTXs show higher interaction with the aerogel and lower desorption rates (below 50%). The silica aerogel-like adsorbent was characterized, before and after equilibrium with BTXs and PAHs solutions, by thermogravimetry (TG), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The ability of this aerogel for removing all these pollutants from a real gasoline sample has also been tested. [ABSTRACT FROM AUTHOR]

Natural biodegradable cotton-based materials are one of the promising materials for oil/water separation. However, the high oil retention ability of the oil/water separation materials benefiting oil transportation and storage is often ignored, and the separation flux of these cotton-based materials is usually unsatisfactory, hindering their applications. In this work, a super-hydrophobic cotton aerogel was prepared through a facile and mild dipping-heating process for oil/water separation. The obtained super-hydrophobic cotton aerogel with high porosity (about 94%), and super-hydrophobic surface (water contact angle as high as 152.7° ± 1.1°, and sliding angle as low as 9.2° ± 0.2°) showed excellent structural strength, allowing them to get an ultra-high separation flux (about 37,000 L m−2 h−1) as well as a high oil retention ability. This work provides a facile approach to fabricating cost-effectively and environment-friendly materials for efficient oil/water separation. [Display omitted] • The PDMS modified super-hydrophobic cotton aerogel has been synthesized by a facile dipping-heating method. • The super-hydrophobic cotton aerogel exhibits super-hydrophobic property with a high water contact angle of about 152.7°. • The super-hydrophobic cotton aerogel shows excellent structural strength. • The super-hydrophobic cotton aerogel shows ultra-high permeation flux (about 37,000 L m−2 h−1) for the chloroform. • The super-hydrophobic cotton aerogel demonstrates a high oil retention ability. [ABSTRACT FROM AUTHOR]

In this work, novel MIL-101(Cr)/polyacrylonitrile/agarose aerogels (MIL-101(Cr)/PANNs/AG) as efficient adsorbents with hierarchical pores were prepared via a facile physical mixture method combining hydrogen bond self-crosslinking without any chemical linkers. The water stability and underwater compressible of the composite aerogel are improved by incorporating polyacrylonitrile nanofibers. MIL-101(Cr)/PANNs/AG aerogels are well characterized systematically and the adsorption performance for 2, 4-dichlorophenoxyacetic acid (2, 4-D) is also measured and investigated. The well-preserved micropores and accessibility of MIL-101(Cr), endow the composite aerogels excellent absorption ability in water treatment and purification. When the mass loading of MIL-101(Cr) nanoparticles is 50%, the composite aerogels reach the large specific surface area of 356.91 m2·g−1. The composite aerogels demonstrate high adsorption ability towards for 2, 4-D (339.87 mg·g−1). [Display omitted] • Novel MIL-101(Cr)/PANNs/AG aerogel was prepared with water stable. • The composite aerogel is compressible by incorporating PAN nanofibers. • Surface area of composite aerogel was increased due to massive loading of MIL-101(Cr). • The adsorption capacity of composite aerogel to 2, 4-D was reached to 339.87 mg·g-1. • The composite aerogel exhibits superior regenerability. [ABSTRACT FROM AUTHOR]

Konjac glucomannan/zeolitic imidazole framework-67 (KGM/ZIF-67) hybrid aerogels were prepared as novel adsorbents to remove malachite green (MG) from aqueous solutions. The impacts of adsorption temperature, solution pH, and ionic strength on adsorption capacity were investigated. The results show that ZIF-67 coordinates with the molecular chain of KGM and modifies the KGM aerogel. The adsorption equilibrium time of KZ2 for MG is 150 min. The adsorption process follows the pseudo-second-order and Langmuir models, with a maximum adsorption capacity of 2891.30 mg·g−1 at 30 ℃. MG adsorption using the hybrid aerogels is a spontaneous and endothermic process. This research shows that hybrid aerogels prepared using KGM and ZIF-67 are promising for use in new water purification applications. [Display omitted] • The inorganic-organic hybrid aerogels are fabricated from biopolymer-KGM and ZIF-67. • Ultra-high molecular chain of KGM perform as good carrier for the dispersion of ZIF-67 in the hybrid aerogels. • The KGM/ZIF-67 hybrid aerogels exhibit good recyclable adsorption properties for MG dye. [ABSTRACT FROM AUTHOR]

Converting artificial photosynthesis into value-added chemicals through photocatalytic CO 2 reduction reaction (CO 2 RR) is a sustainable and economical strategy to solve energy and environmental problems. Here, a series of new three-dimensional (3D) MXene/GO/perylene diimide (PDI) composite aerogels were prepared, and an electron transfer network in a π-π stacking form was constructed through self-assembly. The methyl formate (MF) generation rate of the optimized MXene/GO/PDI composite aerogel for photocatalytic CO 2 RR in methanol is 771.1 μmol g−1 h−1, about 8 fold that of the pure MXene/PDI composite catalyst. The substantially improved performance is attributed to the strong coupling heterogeneous interface established by π-π stacked cross-linking network and the Z-scheme heterojunction constructed between MXene/GO aerogel and PDI. Thus, the transmission of photogenerated electrons is accelerated to improve the oxidation-reduction ability at the interface. A tentative mechanism for selective photocatalysis of methanol to MF over MXene/GO/PDI composite aerogels was put forward. This work provides an efficient strategy to prepare non-precious heterostructure photocatalysts for MF production and other related reactions. [Display omitted] [ABSTRACT FROM AUTHOR]

At present, how to develop an economical and efficient solid adsorbent for CO 2 capture at low temperature still remains a challenge. In this work, amine-modified silica (SiO 2) aerogels were achieved by grafting with 3-(Aminopropyl) triethoxysilane (APTES) through a simple ambient pressure drying process, and verified as efficient adsorbents for CO 2 capture. The effects of sol pH value and APTES concentration on the microstructure and CO 2 adsorption property of as-prepared amine-modified silica aerogels (AMSAs) were investigated in detail. A double exponential model was proposed to reveal the kinetics adsorption mechanism of the AMSAs for the first time. It demonstrated that the as-prepared AMSAs were amorphous with a three-dimensional network structure composed of nanoparticles. And the AMSAs presented a high CO 2 adsorption capacity of 3.37 mmol·g−1 at 70 °C. After 10 adsorption-desorption cycles, the AMSAs still kept 87.6% of the original capacity, exhibiting long cycle stability. Moreover, the kinetic adsorption behavior could be well simulated by the double exponential model, and the CO 2 diffusion process was the speed-controlling step in the whole CO 2 adsorption process. The diffusion active energy of AMSAs on CO 2 capture was also calculated. This synthesis method is facile and environmental-friendly, which is of great significance to the large-scale production of SiO 2 aerogel, and may provide a novel reference for the preparation of CO 2 low-temperature adsorbents with high adsorption performance and good cycle stability. [Display omitted] • Amine-grafted SiO 2 aerogel (AMSA) was formed via ambient pressure drying. • The AMSA achieved high CO 2 adsorption ability (3.37 mmol∙g−1) at 70 °C. • The AMSAs possessed a long cyclic life. • Double exponential model was developed to reveal the kinetic adsorption behavior. [ABSTRACT FROM AUTHOR]

At present, how to develop an economical and efficient solid adsorbent for CO 2 capture at low temperature still remains a challenge. In this work, amine-modified silica (SiO 2) aerogels were achieved by grafting with 3-(Aminopropyl) triethoxysilane (APTES) through a simple ambient pressure drying process, and verified as efficient adsorbents for CO 2 capture. The effects of sol pH value and APTES concentration on the microstructure and CO 2 adsorption property of as-prepared amine-modified silica aerogels (AMSAs) were investigated in detail. A double exponential model was proposed to reveal the kinetics adsorption mechanism of the AMSAs for the first time. It demonstrated that the as-prepared AMSAs were amorphous with a three-dimensional network structure composed of nanoparticles. And the AMSAs presented a high CO 2 adsorption capacity of 3.37 mmol·g−1 at 70 °C. After 10 adsorption-desorption cycles, the AMSAs still kept 87.6% of the original capacity, exhibiting long cycle stability. Moreover, the kinetic adsorption behavior could be well simulated by the double exponential model, and the CO 2 diffusion process was the speed-controlling step in the whole CO 2 adsorption process. The diffusion active energy of AMSAs on CO 2 capture was also calculated. This synthesis method is facile and environmental-friendly, which is of great significance to the large-scale production of SiO 2 aerogel, and may provide a novel reference for the preparation of CO 2 low-temperature adsorbents with high adsorption performance and good cycle stability. [Display omitted] • Amine-grafted SiO 2 aerogel (AMSA) was formed via ambient pressure drying. • The AMSA achieved high CO 2 adsorption ability (3.37 mmol∙g−1) at 70 °C. • The AMSAs possessed a long cyclic life. • Double exponential model was developed to reveal the kinetic adsorption behavior. [ABSTRACT FROM AUTHOR]

Using epichlorohydrin as a cross-linking agent for cellulose and red radish pigment (R) as a pH-smart response indicator, a network-like cross-linked cellulose aerogel film (R-CEF) with water-responsive properties for visualizing pH changes was constructed by a simple method. In R-CEF, epichlorohydrin cross-linked cellulose aerogel film (CEF) as a smart responsive substrate provides a cross-linked structure with high porosity and good compatibility with R. XPS and FTIR structural analysis elucidate the objective fact of the existence of hydrogen bonds and intermolecular interactions between R and CEF. SEM showed that the addition of R changed the network cross-linked structure of CEF, making the original sponge structure into a layered structure after absorbing water, showing the intelligent response characteristics of R-CEF-7 in contact with water. The color change of the manufactured indicator (R-CEF-7) is evident from red to pink in acidic (pH=3 to pH=5) and from pink to yellow in alkaline (pH=10 to pH=13). Furthermore, R-CEF-7 showed good antibacterial properties and intelligent response characteristics to different pH values due to the contribution of R. This study provides new insights into the design and construction of pH-responsive and water-responsive cellulose-based smart composites. [Display omitted] • A pH-responsive red radish cellulose-based aerogel film (R-CEF) was constructed. • Cellulose-based aerogels with cross-linked structure have good compatibility with R. • R-CEF is able to display the pH values visually through color changes. • R-CEF is responsive to water and changes its microstructure when exposed to water. [ABSTRACT FROM AUTHOR]

The hydrophobic (surface modified) silica aerogel (MSA) and hydrophilic (hydroxyl-group) silica aerogel (HSA) were prepared by ambient pressure drying method. The larger specific surface area was obtained in MSA (880.47 m 2 g −1 ) and HSA (628.52 m 2 g −1 ) compared with common silica aerogel. The ability of removal of Rhodamine B (RhB) and Methylene blue (MB) from aqueous solution was examined. Results showed that the maximum adsorptions of MB were 65.74 mg/g, 47.21 mg/g for MSA and HSA, respectively. The maximum adsorptions of RhB were 134.25 mg/g and 185.61 mg/g for MSA and HSA, respectively. Herein, the Langmuir, Freundlich isotherm models were employed to discuss the adsorption behavior. The results indicated that the equilibrium data were perfectly represented by the Langmuir isotherm. At the same time, Pseudo-first-order and pseudo-secondorder models were employed to analyze the kinetics data and the adsorption behavior can be better described by pseudo-second-order model. Silica aerogel as alternative adsorbent can be used for dye removal in wastewater treatment processes in the future environment governance. [ABSTRACT FROM AUTHOR]