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In this study, a shear-stiffening composite porous material (PU@CS) was developed using the dipping-drying technique, with polyurethane (PU) as the substrate. PU@CS not only overcomes the cold flow drawbacks of shear-stiffening gel (SSG) but also significantly enhances the mechanical properties of PU (with a one-order-of-magnitude increase in maximum storage modulus). The introduction of multi-walled carbon nanotubes (MWCNTs) overcomes the electrostatic aggregation drawback of PU. Due to its outstanding shear hardening effect, PU@CS exhibits superior explosion-proof compared to PU, and when filled to a length of 50 cm, it achieves complete quenching of hydrogen gas explosion flames, with a maximum explosion overpressure attenuation ratio of 87.2%. This work provides data support for the application of SSG in the field of explosion protection. [Display omitted] • Shear stiffening gel was applied in the explosion-proof for the first time. • The shear-stiffening composite explosion-proof material was prepared. • PU@CS has excellent antistatic properties and its explosion-proof mechanism is revealed. [ABSTRACT FROM AUTHOR]

In this work, a hydrophobic intumescent flame retardant (HIFR) based on ammonium polyphosphate (APP), tannic acid (TA), CuO and polydimethylsiloxane (PDMS) was fabricated via an aqueous phase reaction. The surface of the HIFR was coated with spherical CuO nanoparticles and has a water contact angle of 130.6°. In comparison with APP, the HIFR exhibits higher flame-retardant efficiency and weakens the negative impact on the mechanical properties of TPU. The introduction of the 4 wt% HIFR results in 29.4%, 9.9% and 86.3% reduction in the peak heat release rate, total heat release and total smoke production of TPU, respectively. Meanwhile, TPU/4HIFR displays an increase in the Young's modulus, tensile strength and elongation at break of 8.3%, 13.1% and 12.2%, respectively, compared with TPU/4APP. It is of great significance to fabricate polymer composites with excellent flame retardancy and respectable mechanical properties. This work proposes a feasible strategy for the design of high-performance polymers with serviceable mechanical properties and low flammability, expecting to explore a series of practical applications in industry. [ABSTRACT FROM AUTHOR]

This study proposes a simple and feasible method to prepare hydrophobic structure, and it has been a fortuitous finding. In our previous research, triethyl phosphate was adsorbed on a porous metal–organic framework and scanning electron microscopy images showed that plenty of mastoids had grown on its surface. This inspired us towards the special surface structure of the lotus leaf. Therefore, we improved the experimental scheme and coated the surface of MOF with polydimethylsiloxane. Compared with that of the original MOF, the water contact angle of the hydrophobic MOF (S-Fe-MOF) increased from 31.9° to 122.0°, displaying remarkable hydrophobicity. The cone calorimetry tests and thermogravimetric analyses also confirmed that the S-Fe-MOF significantly improved the flame-retardant property and thermal stability of polystyrene. This study gives inspiration for the design of hydrophobic structures and provides enlightenment for the preparation of multifunctional materials. [ABSTRACT FROM AUTHOR]

The combustion of polystyrene (PS) releases enormous amounts of smoke and heat, which seriously affects individuals and property safety. This research employed a porous metal–organic framework (P-Fe-MOF) with excellent adsorption properties to fix 1,1'-bis(diphenylphosphino)ferrocene (BDF) into its porous channels to form a novel flame-retardant system. The peak heat release rate (PHRR) of the neat PS is reduced by 49.3% (from 1128 to 572 kW m−2) with the addition of 3 mass% of D-Fe-MOF, while the time to reach the peak is delayed form 170 to 250 s. Additionally, there is an obvious enhancement in thermal stability. The temperature at initial mass losses is significantly delayed from 331 °C for bulk PS to 379 °C for PS/D-Fe-3.0. And the char residue at 700 ℃ is increased from 1.27 to 3.24 mass%. Compared with pure PS, the char residue of PS/D-Fe-MOF is continuous and dense due to the excellent catalytic performance of D-Fe-MOF in the combustion of composites. This research presents a new flame-retardant design strategy and reduces the fire risk of PS, which provides valuable enlightenment for broadening the application field of MOF and improving the comprehensive properties of polymers. [ABSTRACT FROM AUTHOR]

NH 3 ·H 2 O can result in severe accidents when leaking in a confined space. In this work, a novel powder-water mist synergistic strategy for decontaminating NH 3 ·H 2 O in a confined space is proposed. Initially, FeCl 3 /AlCl 3 was employed to modify diatomite, decorating its pore structure and augmenting the number of acidic adsorption sites. The modified diatomite achieves a notable efficiency of 74.6%, surpassing that of the raw diatomite (43.8%). Subsequently, surfactants were introduced to increase the contact area between the water mist and NH 3 , while a thickening agent was employed to suppress the fluidity of NH 3 ·H 2 O. Ultimately, the powder-water mist synergistic decontamination system was constructed by integrating the diatomite with a thickening agent and water mist containing surfactants. The synergistic system exhibits a superior decontamination efficiency of approximately 80%. This work generates fresh insight into decontaminating NH 3 ·H 2 O in a confined space and offers a crucial avenue for future advancements in decontamination technology. [Display omitted] • A novel powder-water mist synergistic decontamination method is presented. • Modified treatments enhance the decontamination efficiency of diatomite on NH 3 ·H 2 O. • This synergistic method exhibits satisfactory decontamination effects on NH 3 ·H 2 O. [ABSTRACT FROM AUTHOR]

The surface of ammonium polyphosphate is modified by layered silicates (kaolinite or functionalized kaolinite). The thermogravimetric analysis data confirm that the layered silicates significantly strengthen the thermal stability of polypropylene (PP) and increase the char residue. Fire safety of PP containing different percentages of modified ammonium polyphosphate and charring–foaming agent is assessed by using limiting oxygen index (LOI) and UL-94 vertical combustion. The addition of layered silicates in polymers can effectively enhance the flame-retardant properties including the enhancements in UL-94 rating and LOI results. The flame-retardant mechanism and model are described based on the results of thermal degradation and char residue analysis. [ABSTRACT FROM AUTHOR]

The harmless treatment and resource utilization of chromite ore processing residue (COPR), a consequential byproduct of chromate production, carry profound significance. In this study, corn stalk, an agricultural waste, was used to generate reducing substances through high-temperature and vacuum treatments and was successfully used to detoxify COPR. The acid leaching method combined with multi-step purification was employed to extract iron and aluminum, two crucial metallic elements, from COPR. The successful preparation of iron hydroxide and ultrafine aluminum hydroxide (ATH) was achieved. The prepared ATH has an average particle size of 8.124 μm, with a highly uniform distribution, enabling it to be a promising environmentally friendly inorganic flame retardant. This study not only effectively addresses the issue of pollution caused by COPR but also presents a novel approach to utilizing industrial and agricultural wastes, thereby promoting the maximization of resource utilization. [Display omitted] • Detoxification of COPR was accomplished by utilizing agricultural solid waste CS. • The tiered utilization of COPR enabled the transformation of waste into treasure. • ATH with good thermal stability and uniform particle size distribution was prepared. [ABSTRACT FROM AUTHOR]

The possibility of layered melamine-phytate (MEL-PA) as an efficient synergist for intumescent flame retardant (IFR) is explored. The synergistic effects of MEL-PA on polypropylene (PP)/IFR composites are investigated in terms of flammability tests and combustion under forced-flaming condition. The addition of MEL-PA can effectively improve limited oxygen index (LOI) of PP composites. When 2 mass% MEL-PA is incorporated, the LOI value is enhanced from 33.0 to 35.1%. In addition, fire-retardant performance is increased with the addition of MEL-PA. The heat and smoke releases of PP/IFR are greatly reduced by MEL-PA. When IFR is partially replaced by 0.5, 1.0 and 2.0 mass% MEL-PA, total smoke production values are decreased by 27.2%, 34.8% and 57.6%, respectively. Raman spectra analysis indicates that the adding of MEL-PA results in higher graphitization degree of char layer. This work proves that MEL-PA and IFR have a good synergistic effect on flame-retardant PP. [ABSTRACT FROM AUTHOR]

• Nacre-like GO-PTA paper is prepared by evaporation-induced self-assembly method. • Fire sensor-based GO-PTA exhibits ultrasensitive and durable warning response. • Enhancement in fire resistance of GO is attributed to in situ phosphorus doping. A novel nacre-like flame-retardant paper based on graphene oxide (GO), and phytic acid (PTA) is fabricated via evaporation-induced self-assembly. This facile method is time saving and low energy consuming. A facile approach is proposed to improve thermal oxidative stability of GO paper by in situ phosphorus doping during flame exposure. Then fire-alarm system is designed based on the high-temperature thermal reduction characteristic of GO. The GO paper functionalized with PTA (GO-PTA) can provide ultrasensitive, reliable and longtime fire early-warning signal. Fire alarm can be triggered at approximately 0.50 s when GO-PTA samples are attacked by fire. Phosphorus atoms are in situ doped into graphene layers during fire exposure, endowing GO-PTA paper with outstanding thermal oxidative stability, and thus alarm duration time of GO is greatly improved. The work develops advanced fire detection and early-warning sensors that provide reliable and continuous signals, which provide more available time for fire evacuation. [ABSTRACT FROM AUTHOR]

This work explores the possibility of ammonium polyphosphate (APP) as the inhibitor for starch dust deflagration. The flame propagation behaviors of starch dust samples are investigated in a half-closed vertical duct. Flame images and temperature are recorded by high speed camera and fine thermocouples, respectively. The high speed photographs indicate that flame propagation and flame luminous intensity of starch dust at the initial stage are greatly suppressed by APP. Maximum temperature values are also significantly decreased by APP. Thermal decomposition behavior and kinetics of starch samples are studied to ascertain the influence of APP on the decomposition activation energy. The combustion heat release of starch samples are tested by pyrolysis combustion flow calorimetry. Inhibition mechanisms of APP on starch dust deflagration are concluded according to the results of flame propagation, thermal decomposition kinetics and heat release. This work proposes a new strategy for exploration of inhibition mechanisms of dust explosion. Image 1 • Flame propagation behaviors of starch dust deflagration were investigated. • Thermal decomposition kinetics of starch samples were studied. • The inhibition mechanisms of APP on starch dust deflagration were ascertained. [ABSTRACT FROM AUTHOR]

Melamine-phytate (MEL-PA) nanoflakes are formed by supramolecular self-assembly technology using melamine (MEL) and bio-based phytic acid (PA) as the building blocks. This work explores the possibility of this two-dimensional nanomaterial as flame retardant. The layered MEL-PA with the loading of 1, 2 and 3 wt% are incorporated into polypropylene (PP) matrix. MEL-PA is dispersed well in the PP matrix. Thermal stability and flame retardant performance of PP/MEL-PA composites are investigated. Compared with neat PP, the addition of 2 wt% MEL-PA decreases the peak heat release rate from 756 to 608 kW/m2. Char yield of PP is improved by MEL-PA, and the chemical structure and graphitization degree of residual char are studied to reveal flame retardant mechanism. [ABSTRACT FROM AUTHOR]

Fast and effective cleanup of viscous crude oil spills remains a global challenge. Herein, by coating the melamine sponge (MS) with a bio-based flame retardant, reduced graphene oxide (rGO) and carbon nanotubes (CNTs), we prepared a flame-retardant and photo/electrothermal conversion absorbent (rGO/CNTs/FRMS) for rapid oil/water separation. The multifunctional sponge demonstrates remarkable hydrophobicity (the water contact angle: 140.0°), high oil absorption capacity (48.2–114.9 g g−1) and recyclability (89.5% after 20 cycles). Notably, rGO/CNTs/FRMS exhibits excellent thermal stability, flame retardancy and photo/electrothermal conversion performance. Under 1 sun irradiation or 9 V, the surface temperatures of rGO/CNTs/FRMS rise to 98.8 °C or 123.2 °C within 60 s, respectively. The solar-assisted and Joule-heating rGO/CNTs/FRMS drastically reduces the viscosity of silicon oil, and thus saves absorption time by 29% under 1 sun or 47% under 9 V, respectively. The proposed all-weather oil absorbent design provides a sustainable and promising solution for crude oil spill clean-up. [ABSTRACT FROM AUTHOR]

Abstract A novel multi-component powder inhibitor was prepared by mixing conventional suppressants (ammonium polyphosphate and aluminium hydroxide) with porous kaolinite. The inhibition performance of this developed inhibitor was investigated using a 20-L spherical experimental explosion system. The explosion parameters, such as the maximum explosion pressure, maximum pressure rising rate, and time to peak explosion pressure, were obtained to evaluate the suppression effects. The results show that the multi-component inhibitor exhibits higher suppression performance than the single components. The thermal stability, decomposition behavior, and gaseous products were investigated using thermogravimetric analysis, differential scanning calorimetry, and thermogravimetric-mass spectrometry. The inhibition mechanisms are illustrated using physical and chemical explanations. The current work introduces a new gas explosion inhibitor with high performance resulting from the synergistic effect between its ingredients. Graphical abstract Inhibition mechanisms of the multi-component powder are investigated by explosion experiments and thermal decomposition analysis. Unlabelled Image Highlights • Inhibitor is prepared by mixing porous mineral with conventional suppressants. • Excellent explosion inhibition efficiency is achieved for this powder inhibitor. • Inhibition mechanisms of the multi-component inhibitor are investigated. [ABSTRACT FROM AUTHOR]

Four kinds of transition metal based organophosphorus hybrids are synthesized via facile chemical precipitation and employed as flame retardant additives for polystyrene (PS). With the incorporation of 6.0 wt% CoPPI, NiPPI, FePPI and LaPPI, the peak heat release rate (PHRR) values are decreased by 33.2, 25.9, 37.5 and 31.8%, respectively, indicating the improved flame retardancy. The dramatic suppressions on CO release are also observed. When 6.0 wt% CoPPI, NiPPI, FePPI and LaPPI are added, the reductions on peak CO yield (PCOY) are 50.9, 42.3, 34.3 and 23.9%, respectively, indicating the markedly decreased fire toxicity. Moreover, the obviously decreased peak smoke production rate (PSPR) values and smoke density are observed after their incorporation. In addition, the release of decomposed volatiles is also inhibited by these hybrids, according to the thermogravimetric analysis/infrared spectrometry. Therefore, both flame retardancy reinforcement and toxic effluent elimination of PS are achieved, indicating the enhanced fire safety. [ABSTRACT FROM AUTHOR]

A self-built gas explosion testing platform was used to explore the quenching effect of flame-retardant polyurethane foam on a gas explosion. The effect of the foam's filling position and length on the explosion suppression performance was explored. The results demonstrate that polyurethane foam exhibits an excellent flame-quenching performance, with a minimum of a 5 cm length of porous material being sufficient to completely quench the flame during propagation. Furthermore, the attenuation function of this porous material on the pressure wave is insignificantly affected by the change in ignition energy. Compared with the explosive state of the empty pipeline, the best suppression effect is obtained when the polyurethane foam is 20 cm in length with a filling position at 1.8 m, and the maximum explosion pressure and maximum rise rate are attenuated by 86.2% and 84.7%, respectively. This work has practical significance for the application of porous materials in explosion suppression and explosion-proof technologies in the chemical industrial processing and oil (gas) storage fields. [ABSTRACT FROM AUTHOR]

This work explores the feasibility of using graphene as an effective synergist for intumescent flame retardant (IFR). The flammability test and fire behavior under different fire scenarios are investigated. The incorporation of graphene results in different responses of IFR/polypropylene (PP) composites to small fire tests and burning under forced-flaming condition. The addition of graphene weakens the reaction of flame retardant PP to small flame. Lower loading of graphene is observed to improve the swelling of char, resulting in better insulation of the char and decrease in heat and smoke release. The further increase of graphene leads to the worsened fire safety. Flame retardant mechanism and model are proposed on the basis of the analyses of thermal decomposition products and process, and melt viscosity change. This works provides a solution to comprehensively assess the synergistic or antagonistic effect of graphene, and will be beneficial to developing its flame retardant mechanism. [ABSTRACT FROM AUTHOR]

A layer-by-layer (LBL) assembly coating composed of α-cobalt hydroxide (α-Co(OH) 2 ) and sodium alginate (SA) is deposited on flexible polyurethane (FPU) foam to reduce its flammability. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) are employed to prove the LBL assembly process. It is obvious from SEM results that a uniform and rough coating is deposited on FPU foam compared with that of untreated one. The peak intensity of methylene of SA in FITR spectra and typical (003) diffraction peak of α-Co(OH) 2 nanosheets at 11.0° in XRD patterns increases gradually with increment of bilayer number. Combustion behavior and toxicity suppression property of samples are characterized by cone calorimeter (under an irradiance of 35 kW m −2 ) and Thermogravimetry/Fourier transform infrared spectroscopy. The one and two bilayers (BL) coating on FPU foam can achieve excellent flame retardancy. Compared with untreated sample, the peak heat release rate of the coated FPU foam containing only one BL coating is reduced by 58.7%. The content of gaseous toxic substances during pyrolysis of FPU foam deposited with a single bilayer coating, such as CO and NCO-containing compounds, are reduced by 20.0% and 9.2%, respectively. Besides, the flame retardant mechanism of the coated FPU foam is also revealed. [ABSTRACT FROM AUTHOR]

Artificial nacre-like inorganic-organic hybrid films are fabricated by a facile evaporation-induced self-assembly method using graphene oxide (GO) nanosheets as rigid bricks and a natural polysaccharide of sodium alginate (SA) as soft mortar. To further improve tensile mechanical properties of the GO/SA films, Ca 2 + is utilized as a substitute for the most widely used glutaraldehyde to crosslink the films. Owing to the high chelation affinity for metal ions, the Ca 2 + modified (Ca-GO/SA) films show higher tensile mechanical properties than those of the original samples. Water uptake in the Ca-GO/SA film is greatly decreased and water stability is improved by the introduction of Ca 2 + . The Ca-GO/SA films exhibit water-triggered shape recovery behavior. The films show two-way shape memory effect and possess two original shapes, which can be reversibly transformed by immersion in water and removal of the absorbed moisture. This advanced hybrid film will broaden the applications for biomimetic materials and shows potential for applications in the fields of water-sensitive actuators and sensors. [ABSTRACT FROM AUTHOR]

B, N- and P, N-doped reduced graphene oxide (RGO) are prepared through high temperature annealing method using boric acid and phosphoric acid as the B and P sources, respectively. The synthesized RGO and dual-doped RGO are well characterized by Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and transmission electron microscopy. The heteroatoms are found to be introduced into the graphene structure. The low level of doping (approximately 1.10 at%) exhibits significant improvement in thermal oxidative stability of RGO. In comparison with neat RGO, the temperature at maximum weight loss rate of B-RGO and P-RGO increase by as much as 52 °C and 130 °C, respectively. The mechanism for retarding RGO oxidation by B/P doping is clearly proposed. More stable bond configurations are formed in the B/P-doped RGO. The doped B and P atoms reduce the reactivity of carbon active sites and inhibit the carbon gasification. This work will provide an understanding of thermal oxidative stability of heteroatoms-doped RGO, and offer a strategy for fabricating graphene with elevated temperature applications. [ABSTRACT FROM AUTHOR]

The salt impurities in graphite oxide (GO) or graphene oxide usually affects their properties and application. Here, thermal stability and hazard (fire risk) of graphite oxide (GO) assembled films with salt impurities including K 2 SO 4 and MnSO 4 were investigated by C80 micro-calorimeter, thermogravimetric analysis combined with infrared spectrometry techniques. It was found that the metal impurities can significantly increase the release of flammable CO during thermal decomposition of GO, even at a very low content. The mechanisms of thermal instability and fire risk of GO containing metal salts was proposed. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) is modified by melamine (MA) via the strong π- π interactions, hydrogen bonding, and electrostatic attraction. PP composites are prepared by melt compounding method, and GO/functionalized graphene oxide (FGO) is in situ thermally reduced during the processing. The results of scanning electron microscopy and transmission electron microscopy indicate that FGO nanosheets are homogeneously dispersed in polymer matrix with intercalation and exfoliation microstructure. The FGO/PP nanocomposite exhibits higher thermal stability and flame retardant property than those of the GO counterpart. During the thermal decomposition, the intercalated MA is condensed to graphitic carbon nitride (g-CN) in the confined micro-zone created by GO nanosheets. This in situ formed g-CN provides a protective layer to graphene and enhances its barrier effect. The heat release rate and the escape of volatile degradation products are reduced in the FGO-based nanocomposites. [ABSTRACT FROM AUTHOR]

Abstract: Multifunctional designs of biomimetic layered materials are in great demand for broadening their applications. Artificial hybrid films are fabricated using a simple evaporation-induced assembly method, using nacre as the structural model, two-dimensional reduced graphene oxide (RGO) and magnetic graphene (MG) as inorganic building blocks and poly(vinyl alcohol) (PVA) as glue. The nacre-like films exhibit good mechanical performance, such as high stiffness, strength and toughness. The biomimetic materials possess the shielding properties of electromagnetic pollution. MG based nacre-like films present more significant electromagnetic interference (EMI) shielding performance than RGO film, because of a synergism between dielectric loss of graphene and magnetic loss of magnetic nanoparticles. Average EMI shielding effectiveness (SE) reaches ∼20.3dB over the frequency range of 8.2–12.4GHz (X band) for MG hybrid film only 0.36mm thick. The lightweight, flexible and thin MG artificial hybrid films possess good potential for EMI shielding applications. [Copyright &y& Elsevier]

Highlights: [•] Graphene was prepared via a novel and facile solvothermal reduction method for graphite oxide. [•] Most of the oxygen functional groups of graphite oxide were removed. [•] The reduced graphene oxide obtained was featured with bilayer nanosheets. [Copyright &y& Elsevier]

Highlights: [•] Graphene oxide was modified by maleic anhydride grafted polypropylene with a “grafting-to” method. [•] Functionalized graphene oxide/polypropylene nanocomposites were fabricated by melt blending. [•] The improvements in thermal stability of the nanocomposites were among the most significant ever reported. [•] The mechanism for the decrease in ductility of the nanocomposites was investigated with direct and detailed evidence. [ABSTRACT FROM AUTHOR]

Thisstudy provides a facile approach to improving the dispersionof graphene in polymer matrix through a synergetic effect betweentwo kinds of two-dimensional (2D) nanofillers. The nanohybrid basedon graphene and boehmite (AlOOH) was synthesized by decorating AlOOHnanoplatelets on the graphene nanosheets. The graphene nanohybrid/ethylenevinyl acetate copolymer (EVA) nanocomposite showed a more homogeneousdispersion than those of composites containing only a single nanomaterial.The obtained nanocomposite exhibited significant enhancements in thermalstability and mechanical properties, compared with those of neat EVAand composites with only graphene or AlOOH. The temperature at 80wt % degradation for the nanohybrid-based nanocomposite was increasedby 27 °C in comparison with that of neat EVA. Nevertheless, onlya 14 °C improvement and no enhancement were observed for theAlOOH- and graphene-based composites, respectively. Additionally,after the incorporation of nanohybrid in EVA, the tensile strengthincreased by 37.1%, from 12.4 to 17.0 MPa. [ABSTRACT FROM AUTHOR]

• A novel graphene-based composite paper was synthesized via a facile method. • The electromagnetic shielding performance of RGO/ZnO composite paper was explored. • RGO/ZnO composite paper possesses excellent fire resistance performance. Graphene composites that take advantage of lightweight, easy processing and excellent electrical conductivity are promising candidates as functional electromagnetic shielding materials. Herein, zinc oxide (ZnO) nanoparticles were prepared by hydrothermal method and then were introduced into graphene oxide dispersion. The reduced graphene oxide (RGO)/ZnO composite paper was fabricated by evaporation-assisted self-assembly and then reduced by hydrazine hydrate vapor. The results show that the shielding effect of composite paper increases with the increase in the thickness and ZnO dosage. The total electromagnetic interference (EMI) shielding effectiveness of RGO/ZnO composite paper with a thickness of approximately 1 mm is determined as 46.9 dB in the X band. Furthermore, this composite paper has excellent fire resistance. This lightweight and thin RGO/ZnO paper demonstrates a high-performance advanced composite for cutting-edge EMI shielding application in harsh conditions. [ABSTRACT FROM AUTHOR]

Composites based on poly(vinyl alcohol) (PVA) and aluminumhypophosphite(AHP) are prepared by solvent blending. The thermal, mechanical, andcrystallinity properties of the composites are studied. AHP remarkablyimproves the char residue yield during the thermal degradation andcombustion of AHP/PVA composites. The flame retardancy of the compositesis obviously improved. The increased char which protects underlyingPVA from heat and oxygen is one of the key reasons for the improvedflame retardancy. The crystallinity of the composites is decreased.The glass transition temperature (Tg)and the storage modulus of the composites are increased. In the compositewith 15 wt % AHP, limiting oxygen index (LOI) reaches 28.0%, UL-94V-0 rating is obtained, Tgis increasedby 7 °C, and the storage modulus is increased by 17.2% in comparisonwith neat PVA. Moreover, AHP/PVA composites keep high transparenceand maintain most of the mechanical properties of PVA, which is advantageousfor the practical application of the composites. [ABSTRACT FROM AUTHOR]

Large size reduced graphene oxide (RGO) tends to restack or form irreversible agglomerates during the conventional drying. In this work, a facile and efficient drying method, involving freezing–thawing–drying approach, is developed to prepare porous RGO. The RGO exhibits a large pore volume (0.414 cm 3 /g) and specific surface area (294.9 m 2 /g). The RGO can be easily ground using mortar and pestle and be dispersed in solvent by ultrasonication. The RGO shows porous nanostructure and poorly-stacked layered structure. Compared with the RGO dried by conventional method, the RGO dried by this modified process possesses similar structural defect density. The ice crystal formed by liquid nitrogen is expected to prevent the restacking of graphene nanosheets and be beneficial to obtain porous structure. [ABSTRACT FROM AUTHOR]

• Nano-coating was alternately deposited on FPU foam by layer-by-layer assembly. • This nano-coating can effectively reduce the smoke release of FPU foam. • This nano-coating can improve the oil adsorption property of FPU foam. A large amount of smoke release is a significant fire risk in the combustion of flexible polyurethane (FPU) foam, thus smoke suppression should be considered. Moreover, FPU foam is considered as a promising oil–water separation material, but its hydrophilicity and poor selectivity limit the oil adsorption performance. In this work, reduced graphene oxide and iron-based metal–organic framework were employed to modify FPU foam by layer-by-layer assembly and hydrazine hydrate vapor reduction to enhance its smoke suppression and oil adsorption property. The cone calorimeter results indicate that the peak smoke production rate and total smoke production of modified FPU foams are greatly reduced by the assembly nano-coating on the foam surface. Meanwhile, the oil adsorption experiments show that the coated foam possesses high oil adsorption capacity, repeatability and oil–water selectivity and still maintains its adsorption capacity even after 10 cycles. This work provides a new strategy to solving the problem that FPU foam produces lots of toxic smoke during the combustion and prepares a functional adsorption material for oil–water separation. [ABSTRACT FROM AUTHOR]

• Thermokinetic suppression of APP powder on sucrose dust deflagration is researched. • Decomposition products of APP have a composite weakening effect on reaction exotherm. • Crosslinking reaction of PPA catalyzes the formation of more and dense carbon layer. • Suppression mechanisms of sucrose dust deflagration by APP powder is investigated. In this investigation, ammonium polyphosphate (APP) is applied to suppress the deflagration of sucrose dust. Through the systematic research on flame propagation images and temperature, decomposition behavior of powder samples and the compositions of deflagration residue, the suppression performance and mechanism of APP on sucrose deflagration are profoundly summarized. Timing diagrams show that APP contributes to reduce deflagration flame brightness, increases ignition delay time and flame fault area. The minimum inerting concentration of APP for sucrose deflagration is determined to be 8 %. From the collected deflagration flame temperature curves, it is confirmed that APP can delay peak temperature arrival time, weaken temperature fluctuation, and decrease peak values of flame temperature and temperature rising rate. Through the analysis on thermal decomposition of samples and deflagration residue, it is reflected that APP has superior composite suppression effect. It can not only absorb reaction heat, but also decrease deflagration exotherm to improve thermal stability of sucrose particles. Thus, the easily oxidized components in sucrose are protected, and deflagration intensity is effectively weakened. This work provides a new solution for prevention and suppression deflagration of dust waste in sugar industry. [ABSTRACT FROM AUTHOR]

• A novel and sensitive fire early alarm was designed based on GO-BA composite paper. • The sensitivity and stability of this novel alarm was excellent. • Flame alarm mechanism of GO-BA paper was described. Boric acid-modified graphene oxide (GO-BA) paper is prepared by a green and facile water evaporation-induced self-assembly method, and its application as an early fire-alarm sensor is investigated. The nacre structure is constructed by assembling graphene oxide (GO) and boric acid (BA) as brick and mortar, respectively. Compared with pure GO paper, improved thermal-oxidative stability is obtained for GO-BA. GO nanosheets are bonded with BA molecules by forming hydrogen bonds between hydroxyl in BA and the rich oxygen-containing functional groups on GO. Notably, the insulating GO-BA paper can be rapidly thermally reduced to conductive reduced graphene oxide under flame exposure, thus providing an ideal fire-alarm response with a quick flame-detection time of ∼0.8 s. In addition, boron oxide formed under flame attack covers the surface of GO, inhibiting further oxidation of GO paper, and effectively extending the duration time of GO-BA under combustion. These results indicate that the GO-BA paper prepared has a broad prospect in the field of fire early-alarm. [ABSTRACT FROM AUTHOR]

Electrical fire is the most frequently occurred fire accident, and fire sensors with self-cutting and ultrasensitive fire-alarm response capability are urgent to be designed and developed. Herein, conductive reduced graphene oxide paper (RGOP) with hierarchical structure is prepared by a facile evaporation-assisted self-assembly of graphene oxide (GO) dispersion and then reduction by hydrazine hydrate vapor. The oxidative decomposition of RGOP containing sodium chloride (RGOP-NaCl) is promoted by the addition of NaCl. When being exposed to flame, RGOP-NaCl strips are readily ruptured. Based on this distinctive self-cutting performance of RGOP-NaCl under fire attacking, a novel fire detection and alarm device is designed by establishing controlling and operation circuits. Under fire encountering, an ultrafast warning response (approximately 5.3 s) of RGOP-NaCl is triggered. Fire-alarm time of RGOP-NaCl is adjustable by varying the content of NaCl. Furthermore, this RGOP-NaCl has the function of fuse and can cut off the conductive circuit timely under fire attacking. This finding will provide a novel thought for the design of advanced fire-alarm sensor and will also expand the application of graphene paper. Image 1 • Conductive RGOP-NaCl is prepared by evaporation-induced self-assembly method. • This RGOP-NaCl exhibits ultrasensitive fire-warning response. • RGOP-NaCl has the function of fuse and self-cutting performance under fire attack. [ABSTRACT FROM AUTHOR]

• GO-PA paper is prepared by an evaporation-induced self-assembly method. • Fire sensor based GO-PA exhibits ultrasensitive and durable warning response. • Enhancement in fire resistance of GO is attributed to in situ phosphorus doping. Although traditional fire detectors are widely used in many occasions, they still show some limitations, such as slow fire response and poor resistance to severe conditions. Thus, it is urgent to design and exploit early fire-warning device with ultrafast response and flame-retardant ability to provide timely and fast alarm. Herein, graphene oxide paper functionalized with phosphoric acid (GO-PA) is fabricated by a facile and environmentally friendly water evaporation-induced self-assembly approach. Based on the flame-induced electrical resistance transformation characteristic of GO-PA, a fire-warning detector is designed to reliably monitor early fire. Fire alarm can be triggered within 0.5 s when GO-PA samples are attacked by fire. The GO-PA composite paper is more sensitive than GO-based fire sensors reported in the literature. Phosphorus atoms are in situ doped into graphene structure during flame exposure. Combustion reaction of GO is significantly retarded by the incorporated PA, thus fire duration time of GO is greatly improved. This work paves a new way to improve fire detection performance of GO-based sensors. This work provides a guide for the development of advanced fire detection and early-warning sensors to provide reliable and continuous alarm signals. [ABSTRACT FROM AUTHOR]

Organically modified ammonium polyphosphate (APP) flame retardant is prepared by supramolecular assembly method using melamine formaldehyde (MF) resin and phytic acid (PA) as building blocks. Surface characteristics of APP are modified, resulting in the enhancements in water resistance, dispersion in the polymer matrix and their compatibility. This supramolecular assembly modified APP (APP@MF-PA) matches well with charring-foaming agent (CFA) to achieve excellent fire safety for polypropylene (PP), and the superiority over conventional APP is observed. Heat, CO and CO 2 releases of PP are greatly decreased by the intumescent flame retardant (IFR) formulation containing APP@MF-PA and CFA. The modification of APP with MF-PA supramolecules are beneficial to improve the yield, insulation properties, graphitization degree and compactness of char. Flame-retardant mechanisms are demonstrated according to the investigations on gaseous and condensed phase products. This novel and facile modification method provides a new strategy for improving the flame-retardant efficiency of IFR. Image 1 • The surface characteristics of APP were modified by supramolecular assembly. • Fire hazards of PP were greatly reduced by this modified APP and CFA. • Flame retardant mechanisms were proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • FC@NF and T@CF were prepared by LBL self-assembly and soaking methods, respectively. • Fire-retardant performance and mechanism of FC@NF were investigated. • FCF-TENG was fabricated for self-powered sensing in fire scenarios. The fabrics commonly used in architectural decorative materials pose significant fire hazards due to their flammability and rapid fire spread. Moreover, the traditional fire-alarm systems may fail to function properly in complex fire environments owing to power supply disruptions. In this study, we developed a low-cost and eco-friendly flame-retardant conductive fabric-based triboelectric nanogenerator (FCF-TENG) by integrating flame-retardant conductive nylon fabric and polytetrafluoroethylene soaked cotton fabric. This nanogenerator exhibits excellent flame-retardant properties and remarkable energy-harvesting capabilities. The nylon fabric, treated with layer-by-layer self-assembly method, possesses outstanding self-extinguishing capability and melt-dripping resistance. Additionally, the electrical performance of FCF-TENG significantly improves, with a 10-fold boost in conductivity, and the open-circuit voltage increases by 84% to 92 V. Besides, by incorporating the rectifier circuit, the FCF-TENG is capable of completely charging a 1 μF capacitor within 30 s. Furthermore, the FCF-TENG was successfully applied as a self-powered sensor in the fire-alarm system and served as a safety exit indicator for evacuees and fire rescue. This work presents an effective and innovative application of multifunctional smart textiles for energy harvesting and self-powered sensing. [ABSTRACT FROM AUTHOR]

Experiments of partial inerting on flame propagation of starch dust deflagration in a vertical duct were conducted to reveal the differences in flame structure evolutions. Particle pyrolysis and combustion behavior combined with time scale analysis are used to discuss the flame inerting mechanism. The results showed that the inerting process makes the flame front fuzzy, discrete and irregular. The thickness of flame reaction zone increases as O 2 concentration decreases, while the preheat zone decreases accordingly. The pyrolysis rate always controls the flame propagation process under inerting conditions. With the decrease of O 2 concentration, the control effect of pyrolysis rate is gradually weakened, and the effect of combustion reaction rate on flame propagation appears. A physical model of starch dust flame propagation under partial inerting is established, and the inerting process of dust pyrolysis and combustion on the flame structure evolution is further revealed. Unlabelled Image • Partial inerting on dust flame structures has been experimentally investigated. • Inerting significantly influences thermal pyrolysis and gas products release. • Thickness of combustion reaction zone increases in the low oxygen levels. • Suppression mechanism is revealed. [ABSTRACT FROM AUTHOR]

"Dry water" (DW) material is the powder with hydrophobic nano silica particles as the shell and water droplets as the core. The water content in DW is higher than 90%, thus, it is an effective fire extinguishing material. However, when DW is compressed under external pressures, it will crack with the core-shell structure being destroyed. In this work, the water phase in the core is modified as gel phase to enhance the internal pressure resistance of DW powder and its stability. More specifically, the feasibility and optimum preparation conditions of carrageenan gel based dry water (CGDW) material are explored and its fire extinguishing performance is revealed using fire extinguishing experiments. The results indicate that the CGDW powder performs better in fire extinguishing than ordinary ABC dry powder. The CGDW materials are green and environmental friendly, and show broad potentials in various applications. Unlabelled Image • The gel phase is formed in "dry water" powder to enhance its stability. • This preparation is inspired from temperature sensitive carrageenan gel. • Fire extinguishing performance of modified "dry water" powder was investigated. [ABSTRACT FROM AUTHOR]

Highlights • Thermal safety of NH 4 NO 3 -NH 4 H 2 PO 4 mixture was studied. • The decomposition mechanism of NH 4 NO 3 -NH 4 H 2 PO 4 mixture was concluded. • The thermal safety enhancement mechanism of NH 4 NO 3 by NH 4 H 2 PO 4 was investigated. • The thermal sensitivity of NH 4 NO 3 was reduced by the addition of NH 4 H 2 PO 4. Abstract In order to analyze the inhibition effect of the additive on the thermal decomposition characteristics of ammonium nitrate (AN), thermal stability and thermal decomposition behavior of AN and its mixtures with various concentrations of ammonium dihydrogen phosphate (ADP) are systematically investigated by DSC-TG, DSC-TG-QMS and TG-FTIR. Breaking point value of the samples is obtained as an evaluation parameter for thermal safety. Experimental results show that the AN-ADP mixtures show higher onset decomposition temperatures, narrower reaction temperature region and lower enthalpy values than those of pure AN. The main evolved decomposition gases of AN are NH 3 , H 2 O, NO, N 2 O, NO 2 and HNO 3 , while the major gaseous products of the AN mixture with ADP are NH 3 , H 2 O, NO, N 2 O and NO 2. Furthermore, the generation of NO and NO 2 is obviously postponed in the AN mixture. In addition, the breaking point value of AN is markedly improved by ADP. The decomposition mechanism of AN-ADP mixture is concluded and the inhibition mechanism of ADP is proposed. It is concluded that ADP is an effective inhibitor for AN and its thermal stability is effectively enhanced. [ABSTRACT FROM AUTHOR]

Epoxy vitrimers appear as a promising alternative to common epoxy thermoset composites. Nevertheless, the possibilities of applying these materials are limited due to their high flammability which may cause high fire risks. To date, the flame-retardant epoxy vitrimer systems reported in the literature almost all rely on intrinsic flame retardancy to achieve high fire safety; however, the complex and expensive synthesis process hinders their large-scale application. In this work, disulfide-based epoxy vitrimer (EPV) was fabricated with 4, 4′-dithiodianiline as the curing agent, and microencapsulated ammonium polyphosphate (MFAPP) was employed as a potential additive flame retardant to improve their fire retardancy. As a comparative study, common epoxy (EP) composites were also prepared using 4,4′-diaminodiphenylmethane as the curing agent. The results showed that the introduction of dynamic disulfide bonds led to a reduction in the initial thermal decomposition temperature of EPV by around 70 °C compared to EP. Moreover, the addition of 7.5 wt.% of MFAPP endowed EP with excellent fire performance: the LOI value was as high as 29.9% and the V-0 rating was achieved in the UL-94 test (3.2 mm). However, under the same loading, although EPV/MFAPP7.5% showed obvious anti-dripping performance, it did not reach any rating in the UL-94 test. The flame-retardant mechanisms in the condensed phase were evaluated using SEM-EDS, XPS, and Raman spectroscopy. The results showed that the residue of EPV/MFAPP7.5% presented numerous holes during burning, which failed to form a continuous and dense char layer as a physical barrier resulting in relatively poor flame retardancy compared to EP/MFAPP7.5%. [ABSTRACT FROM AUTHOR]

Polystyrene (PS) composites with different loading level and proportions of CNAPP20 [i.e., ammonium polyphosphate (APP) wrapped graphitic carbon nitride (g-C3N4), where mass ratio of g-C3N4 to the CNAPP was 20%] to aluminim phosphinates were fabricated. The results indicated that the additives had good interfacial interaction with PS matrix. It is noted that only the PS-1 achieved the UL-94 V-0 rating, and value of limited oxygen index was also the highest among all the composites. The peak of heat release rate (pHRR) and total heat release of all the composites were greatly reduced as compared to those of virgin PS (77.5% decrease in pHRR for PS-1). Combining CNAPP20 with DAHPi (i.e., aluminim diethylphosphinate) induced the formation of a cohesive and uniform carbonaceous residue. In addition, the concentration of carbon dioxide, smoke and carbon monoxide was reduced upon incorporation of CNAPP20 and DAHPi. The property improvements were attributed to the explanations that the formed continuous and dense char residues acted as protecting layers to prevent the heat and mass permeation, and that the evolved gas diluted the oxygen, which retarded the further combustion of flammable compounds. Also, the generated free-radical scavengers retarded polymeric chain breakage. [ABSTRACT FROM AUTHOR]

High frequency (HF) signal injection is an effective sensorless control scheme for interior permanent-magnet synchronous motor (IPMSM) drives to achieve low and zero speed operation. However, the audible noise produced by the injected HF signal is often very shrill and harsh to hear, which restricts the actual application. In order to reduce the audible noise, a novel pseudo-random HF square-wave voltage injection scheme is proposed in this paper. The HF voltages with two different frequencies are randomly injected into the estimated rotor reference frame cycle by cycle, and a corresponding signal demodulation method for extracting the rotor position information is presented. Based on the principle analysis of this random frequency injection scheme, the digital time-delay effect in HF signal is considered and a compensation method for signal demodulation is proposed, which is effective in reducing position estimation error. Then, the power spectra density (PSD) in fixed frequency and pseudo-random frequency injection schemes are compared both theoretically and experimentally. The distribution of HF voltage and current PSD is extended by using the proposed injection scheme. Finally, this sensorless control method is verified by simulation and experiment on a 2.2-kW IPMSM drive platform. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel inhibitor was synthesized by supramolecular self-assembly. • This inhibitor exhibits a prolonged suppression effect on CH 4 /H 2 /air explosion. • A comprehensive inhibition mechanism is revealed. • By virtue of lotus leaf-like appearance, the hydrophilicity of inhibitors is weakened. A novel inhibitor of PA-MEL@NH 2 -Al 2 O 3 was synthesized by using supramolecular self-assembly technique with phytic acid (PA) and melamine (MEL) as the building blocks. Bauxite is a kind of mining waste, which is abundant in Al 2 O 3 and is used as loading matrix. By right of lotus leaf-like structure, the hygroscopicity of PA-MEL@NH 2 -Al 2 O 3 is greatly weakened. The feasibility of inhibiting CH 4 /H 2 /air explosion by different concentrations of PA-MEL@NH 2 -Al 2 O 3 was explored in a 20 L Spherical explosive vessel. The optimum inhibitory effect is obtained when the concentration is 0.25 g/L. The maximum pressure (P max) and maximum pressure rise rate ((dP/dt) max) decrease by 52.41 % and 83.50 % respectively. The induction time and the time to maximum pressure are prolonged to 193 and 400 ms, respectively. The synergistic inhibition mechanism of physics and chemistry is illustrated in the analysis of post-explosion residues. This work provides an efficient and promising approach for the suppression of CH 4 /H 2 /air explosion by synthesizing the prolonged action inhibitor with a lotus leaf-like structure. [ABSTRACT FROM AUTHOR]

The effects of adhesive (layer) on fire performances of structural insulated panel (SIP) have been mostly ignored. This research studied modifications to the epoxy resin adhesive (EA) with expandable graphite (EG), ammonium polyphosphate (APP) and calcium carbonate (CaCO3) to prepare an intumescent flame-retardant epoxy resin adhesive (FREA) which was applied to expanded polystyrene (EPS), a typical core material of SIPs. It was found that the FREA had a char yield of 33% which was 7.6 times of that of EA and a higher viscosity than EA. The limiting oxygen index reached a maximum of 37.7% and UL94 passed the V-0 rating when the EPS was coated with FREA, of which the fire performance was even better than flame-retardant EPS. Additionally, the heat release rate, production rates of CO, CO2 and soot and sample back temperatures were all reduced compared to the EPS coated with EA. Avoiding the sample surface recession in the cone calorimeter, the custom-made spray gun system proves that the FREA can significantly increase the ignition time and lead to self-extinguishment. The degradation products of APP crosslink with CaCO3 to produce phosphates which bond with expanded EG forming the char layer to prevent heat and flame. The use of flame-retardant adhesives can lead to a sufficient fire safety level for the core material without affecting its functions. [ABSTRACT FROM AUTHOR]

Cables are the most common combustibles in nuclear power plants (NPPs) and cable fires are the one of main threaten to the safety of NPPs. Fire characteristics and fire hazards for two typical cables used in NPPs were comparatively studied based on cone calorimeter and cable tray fire tests. The heat release rate (HRR) curves show different patterns, two-peaks and three-peaks for NPP and conventional flame retardant cables, respectively. This difference is attributed to the fire barrier, which distinguishes the burning of sheath and insulation. Moreover, the maximum value of HRR for conventional flame retardant cable is much higher than NPP flame-retardant cable, and the difference is 108 kW m−2. The time from first peak to second peak for NPP flame-retardant cable is approximately four times as conventional flame retardant cable. Based on cable tray fire, the burning time after burner off is much longer for conventional flame retardant cable and its total mass loss is 0.52 kg, which are three times and five times as much as NPP flame-retardant cable, respectively, and it has a self-sustaining stage during cable burning. The above indicates that the NPP flame-retardant cable has less sustained damage, fire development rate and overall fire hazard. In addition, spacing has little effect on the burning time of sheath, but the burning of insulation layer is promoted, the time from first peak to second peak decreases with the increase in spacing. However, the influence of spacing is non-monotonous in cable tray fire, and the burning of cables with 10 mm spacing has higher fire hazard with a maximum mass loss rate. [ABSTRACT FROM AUTHOR]

Increasing contamination risk from oil/organic liquid leakage creates strong demand for the development of absorbents with excellent hydrophobicity and absorption capacity. Herein, bagasse was carbonized to form porous char with a special structure of array-style and vertically perforated channels, and then the activation process enlarged the pore volume of the char. With the cooperation of low-surface-energy polydimethylsiloxane and diatomaceous earth particles, the modified activated carbon aerogel (MACA) was fabricated by modifying the surface coating and mastoid structure on the bagasse char. Moreover, the MACA demonstrates high porosity oil-water separation, hydrophobicity, and considerable absorption capacity (4.06–12.31 g/g) for gasoline and various organic solvents. This work converts agricultural waste into an efficient porous adsorbent, offering a scalable and commercially feasible solution to solving the leakages of oil/organic solvents. [ABSTRACT FROM AUTHOR]

Nano-architecture on the flexible polyurethane foam (FPUF) was built by layer by layer (LbL) self-assembling of α-zirconium phosphate (α-ZrP) and two biopolymers. Through electrostatic attraction and hydrogen bonding between α-ZrP, chitosan and alginate, the nano-coatings were successfully deposited on the substrate. The LbL self-assembly coatings were characterized by X-ray diffraction, UV–vis absorption spectroscopy, attenuated total reflection Fourier transform infrared spectroscopy and scanning electron microscopy. This loaded nano-coating endowed FPUF with excellent flame retardancy. Compared with pure FPUF, the reduction in the peak heat release rate of the modified foam with 12.3 wt% weight gain was achieved 71%, and the melt-dripping during combustion disappeared. Meanwhile, the thermal degradation of coated FPUF under nitrogen atmosphere was obviously retarded compared with pure FPUF. Additionally, the mechanical properties of the treated FPUFs were investigated. After loaded with 12.3 wt% nano-coating, the tensile and tear strength were enhanced by 13% and 54%, respectively. These investigations indicated that the study has great potential to add new dimensions in the fire retardancy modification of FPUF. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional smart textile was fabricated by a simple impregnation method. • Excellent flame retardancy, electrical conductivity and hydrophobicity were acquired. • Self-powered triggered fire-alarm system was designed and engineered. The domain of smart textiles represents a widely researched area, showcasing promising prospects. Herein, a multifunctional smart textile (CF@PM-AA) has been designed and fabricated, amalgamating flame retardancy, electrical conductivity, and hydrophobicity into a unified entity. The flame retardant, synthesized through the reaction between amino trimethylene phosphonic acid and allantoin, was impregnated into cotton fabric through a facile impregnation method. Through surface modification with polydimethylsiloxane and multi-walled carbon nanotubes, the obtained CF@PM-AA acquires exceptional hydrophobic and acid-base environment durability. Significantly, the electrical conductivity of CF@PM-AA is greatly enhanced, with a reduced resistance down from 15.9 GΩ to 13 MΩ. Based on their electrical characteristics, the copper sheet and CF@PM-AA function as the electrode and friction layers, respectively, in the construction of the triboelectric nanogenerator. This configuration produces a voltage output of up to 125.6 V at a frequency of 4 Hz. Given its outstanding flame retardancy, hydrophobicity, and electrical performance, CF@PM-AA can be integrated into firefighting suits to establish a fire-alarm system with remote signal transmission function, enhancing personnel safety. Simultaneously, the CF@PM-AA holds promise for diverse applications in wearable flame-retardant and fire-alarm systems, opening new avenues for smart textile utilization in the Internet of Things domain. [ABSTRACT FROM AUTHOR]

• Luffa sponge was applied in the gas safety protection field for the first time. • An efficient bio-based flame retardant was synthesized. • Most of the raw materials are natural renewable resources. • Flame-retardant luffa sponge has an excellent flame and explosion-proof effect. • The flame and explosion-proof mechanisms of luffa sponge were explored. Porous materials are widely employed in the gas explosion-proof field because of their abilities to dissipate shock wave energy. Luffa sponge is a biomass material with three-dimensional network structure. Thus, it will be a promising porous explosion-proof candidate material. However, luffa sponge is flammable, limiting its development in the flame and explosion-proof field. In this work, a bio-based flame retardant integrating acid catalyst, char-forming agent and foaming source was synthesized. Then the flame-retardant luffa sponge is prepared through impregnation method, and it is employed to the gas explosion-proof field for the first time. The flame-retardant luffa sponge can completely prevent the explosive flame spread, and its explosion overpressure decay ratio can reach up to 84%. The flame-retardant luffa sponge has superior flame and explosion-proof performances, and it can be produced on a large scale. This work provides a novel idea for the research and development of efficient flame and explosion-proof materials by the utilization of renewable resources. [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]

• A porous foam-like biochar was prepared. • The hydrophobicity and photothermal conversion capability were explored. • This biochar possesses excellent adsorption capability for hazardous chemicals. • Photothermal conversion capability promotes its adsorption for viscous oil. Biochar is considered as a promising adsorbent due to its unique porous structure, large surface area and lightweight nature. In this study, pomelo peel was used as raw material, and graphene oxide was introduced as a functional material. High-temperature carbonization was employed to achieve simultaneous carbonization of pomelo peel and thermal reduction of graphene oxide, resulting in the preparation of a porous sponge-like biochar with high hydrophobicity, thermal stability and photothermal conversion capability. This biochar was successfully applied to the efficient separation of various oil–water mixtures, demonstrating excellent cyclic adsorption stability. Furthermore, by harnessing its photothermal conversion effect, efficient absorption of viscous oil product was achieved. This study proposes a facile biochar preparation strategy that can expand its application in the field of oil spill emergency treatment and promote the utilization of agricultural waste. [ABSTRACT FROM AUTHOR]