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In recent years, solar absorbers have received widespread attention, however, large‐scale preparation is difficult to achieve for many absorbers, and the raw materials are expensive. Halloysite (HNTs) and palygorskite (PAL) have the advantage of abundant reserves and low prices. Herein, solar absorbers with bilayer and porous features are prepared from mixed clays of HNTs and PAL; further studies focused on the solar–thermal conversion efficiency of the absorbers. The mixed clays are gelated by aqueous polymerization of acrylamide and N, N′‐methylene bisacrylamide, then the surface of the gel is carbonized to obtain the double‐layer solar absorbers (F‐HNTs/PAL). The F‐HNTs/PAL shows excellent thermal stability with a weight‐loss ratio of 13% at 1,000 °C, good mechanical properties with a compressed strength of up to 200 KPa at 80% strain, abundant porosity with an adsorption pore volume of 0.057 cm3 g−1, and low thermal conductivity (0.206 W m−1 K−1). Under 1 sun illumination, the F‐HNTs/PAL has a higher vapor rate of 1.215 kg m−2 h−1 that equals 84% solar‐to‐vapor efficiency, which is much more than 57% of F‐HNTs prepared by the same methods, but the F‐HNTs/PAL shows unique thermal stability and mechanical property. [ABSTRACT FROM AUTHOR]

Improving solar energy conversion efficiency and salt resistance is particularly important for the practical application of green and sustainable solar steam generation technology. In this work, an interfacial evaporation polypyrrole-coated film was fabricated by the mixed-dimensional clay consisting of 1D palygorskite (Pal), 2D montmorillonite (Mt) and mica, etc., that was intercalated using polyaniline (PANI) and then introduced polyvinyl pyrrolidone (PVP) as pore-forming agent and polyvinylidene fluoride (PVDF) as a base film. The prepared film could efficiently convert light energy to heat under solar irradiation with excellent properties of self-desalination and photothermal conversion efficiency as well as superhydrophilicity and low thermal conductivity. The photothermal conversion efficiency achieved up to 93.6% under the simulated sunlight of 1 kW m−2. The evaporation rate in 15% NaCl brine differed very little from that in pure water, and 0.2 g of NaCl placed on the film would be eliminated in short time at room temperature, which demonstrated that the film had salt resistance and self-cleaning capability. In addition, the resulting film had low thermal conductivity (0.09994 W m−1 K−1) and good mechanical properties (tensile strength of 1.1 MPa) and exhibited superhydrophilicity (water contact angle ~ 0°) which could transport water molecules rapidly. [ABSTRACT FROM AUTHOR]

The development of phase change materials (PCMs) composites with high light‐to‐thermal energy conversion efficiency is of great importance for solar energy storage. Herein, the preparation of novel PCMs composites by incorporation of fatty amines (FAs) into the carbon membranes (CMs) with aligned nanochannels network is first reported, which is obtained by employing an anodic alumina oxidation membrane as sacrificing template and using polypyrrole and asphalt as carbon precursor via a simple carbonization treatment. The carbonized membranes possess abundant porosity and aligned nanochannels, which is beneficial to harvest solar light combined with their carbon in nature. In addition, organic PCMs, i.e. 1‐Hexadecanamine (HDA, ΔH = 311.1 kJ/kg) and 1‐Aminoheptadecane (AHD, ΔH = 293.0 kJ/kg) can be spontaneously loaded into the nanochannels of CMs by the capillary action and surface tension. The fabricated FAs/CMs composites present an enhanced thermal conductivity ranging from 0.291 to 0.525 W m−1 K−1. Compared to pure FAs, the thermal conductivities of the PCMs composites are 144.8–357.1% higher than that of the control. Meanwhile, the as‐synthesized FAs/CMs composites also exhibit a remarkable high photothermal energy storage efficiency of up to 93.8%, which is one of the highest values reported to date, making them promising candidates for a broad range of applications in solar energy harvesting, conversion, and storage. [ABSTRACT FROM AUTHOR]

Summary: The invention of solar steam generation has high energy conversion efficiency and long‐term service cycle, which is crucial for the actual desalination and sewage treatment. Herein, we first time report the fabrication of low‐price, long‐lasting, and durable‐based carbonized tofu (CT) as photothermal materials for highly efficient solar steam generation. On account of super‐hydrophilic wettability and abundant pore, CT shows good performance in transporting water rapidly, combined with its many characteristics such as high light absorption (90%), low heat conductivity (0.093 W m−1 K−1). CT fulfills a high rate of evaporation (1.65 kg m−2 h−1) and conversion efficiency of 87.26% under 1 sun irradiation. Importantly, after 25 days of salt tolerance test, although CT has crystallization on the surface, but can be reused after soaking in water. CT demonstrated excellent salt tolerance and robustness, which shows immeasurable application potential in seawater desalination and wastewater treatment. [ABSTRACT FROM AUTHOR]

Spongy carbon soot (s‐CS) was prepared and used as novel host material of the form‐stable composite phase change materials (PCMs). The s‐CS was constructed by the interconnected and compact large agglomerates of the soot particles with an average size of 25–60 nm. The average pore diameter of the s‐CS was measured to be 15.3 nm. Owing to capillary forces of s‐CS, n‐carboxylic acids can be easily absorbed into the pores and stay stable without leakage. The PCMs/s‐CS composite present a high heat storage capacity between 83.42 J g−1 and 99.63 J g−1, corresponding to the mass fraction of n‐carboxylic acids between 50.10% and 53.20%. The effects of the supporting material on thermal stability and thermal conductivity of composites were investigated by means of thermogravimetry and flash thermal conductivity testing. The PCM/spongy CS composites exhibit excellent thermal stability and durability, and may have great potential for renewable energy saving applications. [ABSTRACT FROM AUTHOR]

Solar steam generation is a highly promising technology for harvesting solar energy and desalination. Here, a new solar steam generation system is introduced based on a surface‐modified polyurethane sponge with bilayered structures for efficient solar steam generation. The top layer, coated with polydimethylsiloxane‐modified graphite powder, serves as light‐to‐heat conversion layer with a broad optical absorption, whereas the lower part of the sponge acts as a thermal insulator with a low thermal conductivity in the wet state (0.13882 W m−1 K−1). In addition, the strong hydrophobic wettability of the top layer (water contact angle: 148°) enables self‐floating behavior on water, which is beneficial for practical applications. The results show that compared with a silver‐nanoparticle‐doped sponge and an acid‐etched sponge doped with silver nanoparticles the graphite‐modified sponge (GS) exhibits the highest evaporation efficiency of 73.3 % under 1 kW m2 irradiation, which is 2.6 times that of pure water and far higher than that of untreated polyurethane sponge (36.0 %). The GS shows excellent stability, and its evaporation efficiency remains unchanged even after immersion in water for one month. Based on its cost‐efficient, simple, and scalable manufacturing process, excellent mechanical stability, and high recyclability, the GS shows great potential as an efficient photothermal material for a wide range of large‐scale applications such as solar steam generation, light absorption, heat localization, and seawater desalination. It's getting steamy: Surface‐modified polyurethane sponges with bilayered structures are used for efficient solar steam generation. They have a great potential for a wide range of large‐scale applications because of their cost‐efficient, simple, and scalable manufacturing process, excellent mechanical stability, and high recyclability. [ABSTRACT FROM AUTHOR]

Solar steam generation based on photothermal materials has emerged as a green and efficient technology for a broad variety of applications, such as solar energy harvesting, desalination, power generation, wastewater treatment, and so on. Herein, the fabrication of a kind of a novel photothermal material that is prepared by simple coating of reduced graphene oxide (rGO) onto commercial hollow polyester fibers (HPFs) for efficient solar steam generation is reported. The as‐resulted rGO‐wrapped HPFs possess a porous structure, low thermal conductivity (0.042 W m−1 k−1), and broad light absorption (85%), which satisfies the criterion for construction of ideal photothermal materials. As expected, a high solar‐thermal efficiency of ≈81% is obtained at 1 kW m−2 irradiation, showing great potential for practical applications based on high solar energy conversion efficiency and a simple and, in particular, scalable manufacturing process. [ABSTRACT FROM AUTHOR]

Solar steam generation has been proven to be one of the most efficient approaches for harvesting solar energy for diverse applications such as distillation, desalination, and production of freshwater. Here, the synthesis of monolithic carbon aerogels by facile carbonization of conjugated microporous polymer nanotubes as efficient solar steam generators is reported. The monolithic carbon‐aerogel networks consist of randomly aggregated hollow‐carbon‐nanotubes (HCNTs) with 100–250 nm in diameter and a length of up to several micrometers to form a hierarchically nanoporous network structure. Treatment of the HCNTs aerogels with an ammonium peroxydisulfate/sulfuric acid solution endows their superhydrophilic wettability which is beneficial for rapid transportation of water molecules. In combination with their abundant porosity (92%) with open channel structure, low apparent density (57 mg cm−3), high specific surface area (826 m2 g−1), low thermal conductivity (0.192 W m−1 K−1), and broad light absorption (99%), an exceptionally high conversion efficiency of 86.8% is achieved under 1 sun irradiation, showing great potential as an efficient photothermal material for solar steam generation. The findings may provide a new opportunity for tailored design and creation of new carbon‐aerogels‐based photothermal materials with adjustable structure, tunable porosity, simple fabrication process, and high solar energy conversion efficiency for solar steam generation. Hollow carbon‐nanotube aerogels with superhydrophilic porous structure, low apparent density, broad light absorption and low thermal conductivity are reported by one‐pot pyrolysis of conjugated microporous polymers nanotubes, which shows a high solar steam generation efficiency of up to 86.8%. The findings of this investigation may open a new route to fabricate carbon‐aerogel materials for solar energy harvesting applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Phase change materials (PCMs) with ideal light-to-thermal conversion efficiency play an important role in solar energy storage and conversion. Hence, we report the fabrication of a novel composite PCMs (CPCMs) device based on ZnO nanorods deposited indium tin oxide (ITO) glass loading with fatty amines. ZnO nanorods were deposited on the ITO glass using a three-electrode electrodeposition method, and 1-Hexadecylamine (HDA) was loaded on the ITO glass via spin-coating, followed by spraying polypyrrole (ppy) on the surface of CPCM device to improve thermal conductivity and solar absorption. The as-prepared CPCM device exhibits excellent light-to-thermal conversion efficiency, achieving a high conversion efficiency of 90.2% obtained at 1sun owing to its high light absorption (80%), enhanced thermal conductivity (improved by 57.8%), and the unique vertical aligned nanorods structure which could significantly decrease tortuosity, thereby reducing thermal route and lowering thermal response time. Furthermore, the electro-to-thermal conversion efficiency of the CPCMs device has also been investigated and the results show that it can reach up to 69.8% under a low voltage of 5 V, indicating that the CPCM device has a high potential in the field of electro-to-thermal conversion. Based on the benefits listed above, the CPCM device may serve an ideal platform for a wide range of solar energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

Epoxy resin, as a thermosetting polymer material with good performance, has been limited in application due to its high flammability. In this investigation, porous CuO-ZnO hollow spheres (CZHS) were prepared by a hydrothermal method. By incorporation with ionic liquids loaded CuO-ZnO hollow spheres (CZHS@Ils) and ammonium polyphosphate (APP) into epoxy resin (EP) matrix, a new composite flame retardant material, named as EP/7.5APP/1.5CZHS@ILs, was developed for improvement of their thermal insulation and flame retardancy. The thermal conductivity of EP/7.5APP/1.5CZHS@ILs was measured to be 0.0197 W m −1 K −1, which is lesser than that of APP incorporated epoxy resin (EP/APP), demonstrating good thermal insulation capability. The flame retardancy were assessed using the limiting oxygen index (LOI) test, the Vertical flame testing (UL-94) test, and the cone calorimeter (CC) test. The results obtained from LOI test show that the EP/7.5APP/1.5CZHS@ILs has good flame retardancy with a LOI value of up to 28, better than that of pure EP which has a LOI value of 19.2. Moreover, a V-0 level of the EP/7.5APP/1.5CZHS@ILs was observed from the UL-94 test. The peak heat release rate (PHRR) was reduced to 257.9 kW m−2, which is 74.8 % lower than that of the pure EP. Such results are attributed to the synergy effect of CZHS@ILs and APP which offers the epoxy resin excellent flame retardancy. Taking advantages of the excellent thermal insulation, flame retardancy and better mechanical properties, the as-resulted EP/7.5APP/1.5CZHS@ILs may hold great potential for future thermal insulation and flame-retardant applications of energy saving building. [Display omitted] • CuO-ZnO composite hollow spheres were prepared by one-pot hydrothermal synthesis. • CuO-ZnO composite hollow spheres were used as the carrier of ionic liquid. • The prepared EP composite has a LOI value of 28 and its UL-94 reaches V-0 level. • Cone calorimetric test results show that PHRR drop to 257.9 kW m-2, which has excellent flame retardancy. [ABSTRACT FROM AUTHOR]

The development of efficient solar photothermal conversion and energy storage composite (SPCSC) is of great significance in solving the imbalance between supply and demand of solar energy utilization in time and space. Herein, we prepare multi-shell hollow spheres by selecting glucose as the template and magnesium carbonate trihydrate (MgCO 3 ·3H 2 O) and chloroplatinic acid hexahydrate (H 2 PtCl 6 ·6H 2 O) as raw materials by hydrothermal-calcination method. Octadecylamine (ODA) is loaded into MSHS by vacuum impregnation to prepare SPCSC with excellent comprehensive properties (MSHS@ODA). The multi-layer hollow microspheres provide the micro-nano space structure for ODA, enhance the heat transfer rate of MSHS@ODA, effectively solve the leakage problem, and enable MSHS@ODA to have a fast photothermal response. MSHS@ODA possesses a high light absorption (75.5%), thermal conductivity (0.35 W·m−1·K−1), and photothermal conversion. The phase change enthalpy can reach 130.7 J·g−1 and maintain a high energy storage density during 100 cyclic phase change tests. Specifically, MSHS@ODA decreases the operating temperature of lithium-ion batteries by 8 °C during discharge, ensuring their stable operation within the optimal temperature range. Based on the above merits, MSHS@ODA may find useful applications in solar thermal storage and effectively managing the thermal conditions of lithium-ion batteries. [Display omitted] • The unique multi-layer hollow cavity structure of MSHS effectively encapsulates PCMs. • The multi-layer structure of MSHS enhances the heat transfer process. • MSHS@ODA has high latent enthalpy, thermal conductivity and good photothermal conversion efficiency. • MSHS@ODA is superhydrophobic and self-cleaning. • MSHS@ODA has better application prospects in battery thermal management. [ABSTRACT FROM AUTHOR]

Materials with thermal insulation and flame retardant properties are highly sought after in construction industry. In this study, two hollow-structured conjugated microporous polymer spheres (HCMPs) were successfully synthesized via the template method by polymerizing 1,3,5-triethynylbenzene with 3-amino-2,6-dibromopyridine and 2-amino-3,5-dibromopyridine respectively. To enhance flame retardant properties, HCMPs were impregnated with ethanol-soluble 6 H-dibenzo (C, E) (1,2) phosphine oxide-6-oxide (DOPO) (named as HCMP-FR), which maintains a hollow structure, enabling it to serve as a heat insulator, as observed under transmission electron microscope (TEM). The two types of HCMP-FR with a thermal conductivity of 0.047 W m−1 K−1 and 0.051 W m−1 K−1 respectively, exhibit excellent thermal insulation property. HCMP-FRs were added in to epoxy resin (EP) composites to further investigate the property of it. Under addition of 1.3%wt HCMP1-FR and HCMP2-FR, the thermal conductivity of EP composites (0.159 W m−1 K−1 and 0.146 W m−1 K−1) decreased by 25.3% and 31.4% compared with pure EP composites respectively, and the density (0.651 g cm−3 and 0.8 g cm−3) decreased by 42.1% and 22.5%, significantly reducing EP's thermal conductivity and density. The cone calorimeter (CC) tests show that the pHRR of EP composites at 0.6%wt addition was 859.04 kW m−2 and 904.35 kW m−2, respectively, which were 17.5% and 13.1% lower than that of pure EP, and the TSP decreased by 44.9% and 41.3% when 1.3% HCMP-FRs was added, which shows an excellent smoke depressing property. Therefore, the HCMP-FRs synthesized have highly promising for application in thermal insulation and flame retardancy of energy saving building. [Display omitted] [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) have been widely used as efficient materials in latent heat thermal storage systems for various applications. The poor thermal conductivity of most organic phase change materials (OPCMs), however, has long been considered as one of big obstacles hindering their practical applications. Here, we report the first examples of Manganese dioxide nanowires and nanotubes based PCM nanocomposites (named as MnO 2 NWs/PCM and MnO 2 NTs/PCM) with enhanced thermal conductivity by simply using MnO 2 nanowires and nanotubes as efficient nanofillers. The PCMs nanocomposites show high latent heat ranging from 140.1 J g −1 to 206.1 J g −1 . The thermal conductivity of PCM nanocomposites were dramatically enhanced by incorporation of Manganese dioxide nanowires and nanotubes with a maximum value of 377.16% of that of pure PA achieved, which is nearly two times of that of control. X-ray diffraction (XRD) analysis shows that the incorporation of nanofillers does not change the crystalline structure of OPCMs while lowering its crystalline size. The PCM nanocomposites also show excellent thermal stability of recyclability. Only a slight loss of 2.8% in latent heat was observed after 100 times of melting/cooling cycles. Based on their high heat storage performance, excellent thermal conductivity and thermal stability of recyclability, the as-prepared PCM nanocomposites may have great potentials for energy saving applications. [ABSTRACT FROM AUTHOR]

The development of materials with both outstanding thermal insulation and excellent flame retardant properties has received considerable attention for preparation of energy-saving materials in construction industry. In this work, 1,3,5-Triethynylbenzene and 1,4-Diethynylbenzene were used as monomers to synthesize two kinds of homo-coupled conjugated microporous polymer hollow nanostructured spheres (HCMPs-NHS), followed by the post-modification of the HCMPs-NHS using diphenyl azide phosphate (DPPA) to react with end alkynyl group via "click chemistry" method (named as HCMPs-NHS-FR). The as-synthesized HCMP1-NHS-FR and HCMP2-NHS-FR have excellent thermal insulation performance, in which thermal conductivity is 0.049 W m−1 K−1 and 0.05 W m−1 K−1, respectively. The peak heat release rate (pHRR) from the microscale combustion colorimeter (MCC) of HCMPs-NHS-FR was 94.834 W/g and 70.799 W/g, respectively. To further explore the flame retardant properties, the HCMPs-NHS-FR was introduced into the epoxy resin (EP) to obtain EP-1 and EP-2, and it was found that pHRR from conical calorimetry (CC) was 496.38 KW/m2 and 596.96 KW/m2, respectively, which was lower than 30.4 % and 16.3 % compared with pure EP. Based on the advantages of superior thermal insulation and flame retardancy mentioned above, the as-synthesized HCMPs-NHS-FR may have enormous potential as flame retardant with good thermal insulation in the future building energy-saving. [Display omitted] • CMPs is firstly synthesized via post-modification using "click chemistry" method. • The samples have low thermal conductivity of 0.049 W m-1 K-1 and 0.05 W m-1 K-1.. • The samples have excellent flame retardancy with pHRR of 94.834 W g-1 and 70.799 W g-1. [ABSTRACT FROM AUTHOR]

The fabrication of composite phase change material (CPCM) with splendid light-to-thermal conversion efficiency and enhanced thermal conductivity is of significance for solar energy storage and transition. Hence, we report the creation of a novel CPCM prepared by impregnating 1-hexadecanamine (HDA) into nickel foam (NF) bearing with carbon nanotubes (CNTs) nanoarray via simple vacuum impregnation for photothermal conversion. The NF bearing with CNTs nanoarray employed in this study show outstanding light absorption of higher than 97% originated from its vertical aligned CNTs nanoarray which makes it possible for trapping the light to the most extent. Moreover, the metal nature of NF coupled with the carbon nature of CNTs nanoarray endow it excellent thermal conductivity, e.g. the thermal conductivity of CPCM is improved by 46.3% compared to that of the pure HDA. Thanks to the high latent heat of HDA (240 J/g), the latent heat of the CPCM are measured to be 132.2 J/g. In addition, it shows excellent thermal stability, e.g. the latent heat of the CPCM remains nearly unchanged after 50 times of melting/freezing cycles. Beneficial from their outstanding light absorption, excellent thermal conductivity and high latent heat, the as-prepared CPCM is an ideal platform solar energy harvesting, storage and transition. Under 1sun irradiation, the light-to-thermal conversion efficiency of the CPCM was measured to be 80.10%. Moreover, we detected the temperature-time curve of the CPCM under 30 V voltage, the result show that the CPCM also has great potential in the electro-to-thermal conversion application. [Display omitted] [ABSTRACT FROM AUTHOR]

The exploitation of photothermal materials (PM) with desired salt-resistance is significant importance for solar steam generation (SSG). Herein, a novel salt-resistant PM based on porous ionic polymers（PIPs）coated with acetylene black (AB) was prepared for efficient SSG (named as PIPs-AB). The PIPs were synthesized using alkynylbenzene and ionic monomers as building blocks by Sonogashira-hagihara cross coupling reaction, which show low thermal conductivity (0.1 W m−1 K−1) and super hydrophilicity (infiltration within 40 ms). By decorated with AB, an excellent light absorption of 90% for the as-prepared PIPs-AB was obtained. Coupling with their superior thermal insulation and desired water transportation ability, the as-prepared PIPs-AB exhibits superior solar conversion efficiency (85.4% under 1 sun illumination). Furthermore, the intrinsically ionic feature of PIPs, combining with the Janus structure composed of superhydrophilic PIPs monolith and hydrophobic AB coating, makes the PIPs-AB excellent salt-resistant ability, e.g. no salt accumulation was observed after 6 h duration at 1 sun irradiation. Taking the advantages of the inherently adjustable chemical composition and tunable porosity of PIPs, the results of this work may open an opportunity for rational design and preparation of high-performance PIPs-based PM with desired salt-resistance for real SSG applications. Novel monolithic solar steam generator was prepared based on acetylene black modified PIPs, whose inherent porous ion skeleton was used as ion barrier to make it with high evaporation efficiency and good self-desalination performance. Image 1 • Superhydrophilic PIPs monolith and hydrophobic AB coating composed structure were prepared for solar steam generation. • They possess high evaporation efficiency of ca.88% under 1 sun irradiation. • Their intrinsically ionic feature nature endows them unique self-desalting performance. • They have advantages of simple and scalable manufacture process. [ABSTRACT FROM AUTHOR]

In order to improve the energy storage and conversion efficiency of phase change materials, a mixed clay sponge (MCS) containing palygorskite (Pal) and Halloysite Nanotubes (HNTs) was successfully constructed by solution polymerization. Expanded graphite (EG) was used to enhance the overall thermal conductivity and carbonized MCS with EG (mark as EG-MCS, C-EG-MCS). A series of form stable phase change materials (FSPCMs) were prepared by using them as scaffolds and encapsulated organic phase-change material 1-Hexadecylamine (HDA) by direct impregnation. By means of SEM, TEM, FTIR, XRD, XPS, DSC, TG, etc., their microstructure, chemical compatibility and thermophysical properties were systematically studied. The DSC results demonstrate that PCM composites exhibit relatively high thermal energy storage density of 214.2 kJ kg−1, 237.5 kJ kg−1 and 239.2 kJ kg−1 respectively. The reliability test shows that the PCM composites retain shape stability and almost no leakage of HDA even after 200 thermal cycles. Compared with the pure component HDA, the thermal conductivity of the as-prepared C-EG-MCS-HDA was improved from 0.147 W m−1 K−1 to 0.667 W m−1 K−1 and EG-MCS-HDA was improved from 0.147 W m−1 K−1 to 0.454 W m−1 K−1 owing to the high thermal conductivity of EG (only 6 wt%). Besides, the light-thermal conversion efficiency of EG-MCS-HDA and C-EG-MCS-HDA is 74.6%, 80.8% respectively. Therefore, the fabricated FSPCMs with high latent heat, good melting/freezing cycles reliability and high thermal conductivity, remarkable light-thermal energy conversion ability which have a broad application prospect in energy conversion and storage devices. Unlabelled Image • 1-Hexadecanamine (HDA) was first exploited as a new class of organic PCMs. • Form-stable PCMs composites were fabricated based mixed clay sponge. • The as-prepared PCM composites exhibit high light-thermal conversion efficiency. [ABSTRACT FROM AUTHOR]

Solar steam generation is a kind of highly promising technology for harvesting solar energy and the production of fresh water. Here, we report the fabrication of a novel Ca2+ crosslinked sodium alginate modified monolithic polypyrrole 3-D conductively porous architecture (M-PPy sponge) with unique micron-sized channels as functional solar steam generator. The as-synthesized M-PPy sponge shows excellent thermal insulation (a low thermal conductivity of 0.0995 W m−1 k−1), superhydrophilicity, nearly 100% light absorption and better mechanical properties. Under a solar light power of 1 kW m−2, a higher evaporation efficiency of 84.72% was achieved, which is comparable to the best performance for polymer systems that have been reported so far. More significantly, the modified monolithic polypyrrole shows the excellent salt-resistant performance in high saline solution with the greater evaporation efficiency of 84.43% and recyclability, making it promising candidate for a variety of applications, including power generation, desalination and so on. M-PPy sponge with unique micron-sized channels was synthesized to have superhydrophilicity, high solar evaporation efficiency, excellent salt-resistant performance and recyclability, making it promising candidate with great potentials for efficient solar steam generation. Image 1 • Ca2+ crosslinked sodium alginate modified monolithic PPy sponge. • The PPy sponge exhibits micron-sized channels, low thermal conductivity, 99% light absorption. • It shows high solar evaporation efficiency, excellent salt-resistant performance and recyclability. [ABSTRACT FROM AUTHOR]

• Fatty amines (FAs) were first exploited as a new class of phase change materials (PCMs). • Form-stable PCMs composites were fabricated by doping of FAs into graphene sponge (FAs/GS). • The FAs/GS shows exceptional high energy density and low supercooling degree. • The FAs/GS shows enhance thermal conductivity, thermal stability and recyclability. • A FAs loading rate of 10,660 wt% was achieved, which is highest value reported to date. The development of form-stable phase change materials (FSPCMs) with large latent heat, excellent thermal stability, and recyclability is essential for their practical applications for thermal or solar energy saving. Here, we first report the exploitation of fatty amines (FAs), in this case tetradecylamine (TDA) and octadecylamine (ODA), as novel organic phase change materials (PCMs) for fabrication of FSPCM composites with exceptional high energy density using porous 3D graphene sponge (GS) as porous supporting materials. The resulting fatty amines/graphene sponge composites (FAs/GS) show high latent heat of ranging from 293 kJ kg−1 to 303 kJ kg−1 and low supercooling degree of 7–9 °C. Surprisingly, it is found that the loading rate of these two FAs into GS is as high as 7063–10660 wt%, which is nearly three orders of magnitudes higher than that of most reported FSPCMs. In addition, compared with the FAs, the presence of GS results in an enhancement of thermal conductivity of FAs/GS. After 200 cycles of thermal cycling, the latent heat content of FAs/GS still remains as high as 93.34% (TDA/GS) and 93.83% (ODA/GS), implying an excellent thermal stability. Taking advantages of the merits mentioned above, the findings of this work would not only open a new way for exploiting the FAs as new high-performance organic PCMs, but also provide a possibility for construction of such FAs/GS with great potentials for real energy-saving applications based on their exceptional high energy density, low supercooling degree, unprecedented high loading value, excellent thermal stability and recycling capacity. [ABSTRACT FROM AUTHOR]

It remains very challenging to create porous materials with both good thermal insulation and flame retardancy for construction of energy-saving buildings. Herein, we report the first example of ionic liquid (IL)-based monolithic porous polymers as efficient flame retardant with good thermal insulation, which was synthesized by polymerization of vinyl tetrafluoroborate ionic liquid monomers with polydivinylbenzene (PDVB) as a crosslinker through a facile solvothermal synthesis followed by freeze drying (named as PDVB-BF 4 ILs). The PDVB-BF 4 ILs is mainly composed of mesopores with a pore sizes ranging from 8.8 to 20.3 nm. The PDVB-BF 4 ILs has a decomposition temperature of higher than 320 °C. The PDVB-BF 4 ILs show high thermal insulation with a low thermal conductivity (0.019W m−1 k−1) in air. Also, the PDVB-BF 4 ILs possesses excellent flame retardancy with a low peak heat released rate (139.3W g−1). Compared with porous PDVB, the pHRR of PDVB-BF 4 ILs was reduced by approximately 75%. Torch burn test implies that the PDVB-BF 4 ILs shows self-extinguishing behavior without generation of any melt dripping, indicating an excellent flame retardancy. Taking advantages of simple fabrication process, easily to be scaled-up, excellent thermal insulation and flame retardancy, such IL-based monolithic porous polymers may have great potential for real applications. Image 1 • Ionic liquid (IL)-based monolithic porous polymers have simple fabrication process. • Ionic liquid (IL)-based monolithic porous polymers show excellent heat insulation property. • Ionic liquid (IL)-based monolithic porous polymers exhibit high flame retardancy. [ABSTRACT FROM AUTHOR]