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[Display omitted] The development and preparation of multifunctional photothermal conversion materials has far-reaching significance for the utilization of solar energy resources in response to the energy crisis. Herein, we propose a Janus membrane for interfacial solar evaporation and phase change energy storage. The membranes were fabricated via combining the PVA film with multi-shelled hollow spheres (MHS). The membranes have asymmetric wettability, that is, one side is hydrophilic and the other side is hydrophobic. The as-resulted membranes obtain outstanding light absorption without further processing. According to these two advantages, the membranes were applied to solar evaporation. The evaporation rate of the membrane is 1.41 kg*m−2h−1 and the evaporation efficiency is 92.4 % under 1sun irradiation. Moreover, the membrane prepared by impregnating 1-Hexadecanamine (HDA) into MHS possesses excellent tensile strength (2.21 MPa) and photothermal conversion ability. The light-to-thermal conversion efficiency can reach 81.9 % under 1sun irradiation. Therefore, the membranes have broad application prospects in the field of photothermal conversion. [ABSTRACT FROM AUTHOR]

Herein, an approach for development of a novel FS-PCMCs by incorporation of FAs into the GCA, which was derived from one-step hydrothermal of C-MWCNTs and GO followed by annealing treatment, through a simple direct impregnation. The FS-PCMCs was developed for solar energy storage. [Display omitted] The exploitation of excellent performance form-stable phase change material composites (FS-PCMCs) with enhanced photothermal conversion efficiency and high phase change latent heat is of great significance for thermal energy storage. In this work, a new type of FS-PCMCs with superior light-to-thermal conversion performance were created by impregnation of organic phase change material (1-hexadecylamine (HDA) and 1-tetradecylamine (TDA)) into the graphene aerogel (GA) and all-carbon aerogel (GCA) through a simple direct infusion. The multiwalled carbon nanotubes (MWCNTs) are wound around the inner wall of the GA layer to form a three-dimensional (3D) porous network structure to support fatty amine (FAs), thus achieving shape stability before and after phase transition. Moreover, the FS-PCMCs has extremely high phase transition enthalpy (203.1–248 kJ·kg−1) and good recyclability. More importantly, due to the high absorbance of GCA, it can enhance its light absorption capacity and reduce thermal radiation. The light-to-thermal conversion efficiency of the FS-PCMCs is 72.36%-88.25%. Taking the improvement of the comprehensive properties of the FS-PCMCs, the results of this work may open up a way for rational design and preparation of high-performance FS-PCMCs with enhanced storage capacity and light-to-thermal conversion efficiency for the efficient utilization of solar energy. [ABSTRACT FROM AUTHOR]

[Display omitted] The inevitable intermittency of solar illumination during the interfacial evaporation process can cause a reduction in the evaporation performance of solar evaporators. Here, we report the fabrication of a new solar-driven interfacial evaporator using MXene nanosheets as the photothermal layer, modifying them with conjugated microporous polymer hollow microspheres, and then compounding them with the phase change material, in this case, cetyl alcohol, to form a composite evaporator (CE) that can perform all-weather solar interfacial evaporation. By combining interfacial evaporation photothermal conversion with energy storage, the evaporator achieves an evaporation rate of 1.57 kg⋅m−2⋅h−1 at a light intensity of 1 kW⋅m−2 and 2.79 kg⋅m−2⋅h−1 at a light intensity of 2 kW⋅m−2. In addition, the evaporator attains an excellent solar evaporation efficiency of over 91% in both cases and even in salt water. In addition, interestingly, our CE exhibits excellent continuous evaporation ability, e.g., the mass of evaporated water was increased by 0.36 kg⋅m−2 at a light intensity of 2 kW⋅m−2 compared to the cavity evaporator without the phase change material (PCM) when solar light was turned off. These results could be attributed to the fact that the energy released by the incorporated phase change material allows the evaporator to maintain stable evaporation under conditions of insufficient or intermittent solar irradiation, potentially providing a new opportunity for addressing the intermittent problem of evaporation at the solar interface due to unstable light intensity, thus showing great potential for practical continuous desalination. [ABSTRACT FROM AUTHOR]

[Display omitted] Solar steam generation is widely used in seawater desalination because of its high efficiency and environmental protection. However, using low-cost materials to produce efficient solar evaporators is a severe challenge. In this study, a porous carbon material was prepared by combining Attapulgite (ATP), Polyethylene glycol (PEG) and Manganese dioxide nanowires (MnO 2 NWs) composite, through freeze-drying and high-temperature carbonization. The prepared CAPM aerogel shows a three-dimensional porous structure, which has high evaporation properties in pure water and simulated seawater. Under 1 sun simulated illumination, the pure water evaporation is 1.4574 kg m-2h−1 and the corresponding energy conversion efficiency is 85.94%. The prepared CAPM aerogel showed excellent durability and salt tolerance in 20%Nacl solution, indicating that the CAPM has excellent desalinization performance. In addition, CAPM aerogel has and exhibits super hydrophilic properties, which can transfer water molecules quickly. Due to the advantages of low cost, simple preparation method, and high solar energy conversion efficiency, the CAPM has excellent potential as a photothermal material for solar energy generation. [ABSTRACT FROM AUTHOR]

In this work, we report the formulation of conjugated microporous polymer membranes (CMPM) with a hierarchical porous structure which was prepared using polyvinylpyrrolidone (PVP) electrospun nanofibers as a template for efficient removal of PM from airborne and vehicle exhaust. Taking advantage of its inherent physicochemical and thermal stability, the CMPM-based filter can work continuously for up to 36 h and still maintain a high removal efficiency (>99.56%), and also have a high filtration efficiency in the treatment of vehicle exhausts, with 95.18% for PM 0.3 , 98% for PM 0.5 and >99% for PM 2.5-10.0. Due to the exceptional mechanical properties of the CMPM, the filter can be washed and recycled and after three cycles the PM filtration efficiency is reduced but still above 94.83%. Additionally, The CMPM-based filter has a filtration efficiency of >95.37% for PM 0.3-10 at high humidity (RH≥95%). [Display omitted] Air pollution has become a challenging environmental problem worldwide due to rapid industrial development and excessive emissions of vehicle exhaust. Herein, we report a preparation of conjugated microporous polymer membranes (CMPM) with a hierarchical porous structure by electrospun polyvinylpyrrolidone (PVP) nanofibers as a template for effective removal of PM from airborne and vehicle exhaust. CMP membranes have hierarchical holes, where the macropores are from electrospun nanofiber membranes and the mesopores are from polymer synthesis. Taking advantage of its inherent physicochemical and thermal stability and hierarchical hole characteristics, the CMPM-based filter can work continuously for up to 36 h and still maintains a high removal efficiency (>99.56%), and also has a high filtration efficiency in the treatment of vehicle exhausts, with 95.18% for PM 0.3 , 98% for PM 0.5 and >99% for PM 2.5-10.0. The superior mechanical properties of CMPM allow the filter to be cleaned and reused. After three cycles, the filtration effectiveness of CMPM is still 94.83% for respirable particulate matter. Under high humidity (RH ≥ 95%) conditions, the CMPM-based filter showed higher than 95.37% filtration of PM 0.3-10 , and the oil adsorption rate could be maintained at 284% at high speed, proving the great potential of CMPM to clean air in complex situations. [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]

[Display omitted] Highly efficient harvesting, transfer, and storage of solar energy are of great significance for the sustainability of society Herein, we report the design and synthesis of conjugated microporous polymers hollow spheres (CMPs-HS) coated by graphene (GCMPs-HS) and compounded with the phase change material (PCM) octadecanol (GCMPs@ODA) for efficient solar photothermal conversion. The as-synthesized CMPs-HS shows a high specific surface (519.95 m2 g−1 and 309.26 m2 g−1), good thermostability, and lower thermal conductivity (0.33 W m-2h−1). By coating graphene, the light absorption remained about 90% in the visible light range, which allows light harvest for photothermal conversion. Taking the GCMPs-HS as a functional layer for the solar steam generation (SSG) system, a high evaporation efficiency of near 90% is obtained. After inhaling octadecanol, GCMPs@ODA are prepared and their latent heats are measured to about 217.4 J g−1 and 224.6 J g−1. Under 1 sun irradiation, the photothermal conversion efficiencies of GCMPs@ODA are measured to be 87.15% and 85.83%, the above merits applied in different conditions are superior to photothermal conversion materials reported in the literature. Thus, among the above merits, the fabricated materials are the competitive candidate which shows the great potential in the efficient application of solar energy. [ABSTRACT FROM AUTHOR]

In this work, we report for the first time the preparation of a kind of novel membrane based on holey Ti 3 C 2 Tx nanosheets (h- Ti 3 C 2 Tx), which was obtained by etching the Co 3 O 4 nanoparticles embedded on Ti 3 C 2 Tx nanosheets followed by a simple vacuum filtration using a polymeric membrane as support, for efficient removal of MPs in wastewater. As a proof-of-concept study, the h-Ti 3 C 2 Tx nanosheets exhibit a planar porous structure that presents nano-holes with an average hole-size of 25 nm in diameter, which facilitated the construction of membranes with better water flux for the separation of MPs (196.7 L m−2h−1 kPa−1). In this care, FP microspheres with different diameter sizes were used as the MPs model, the h-Ti 3 C 2 Tx membrane shows extremely high MPs removal efficiency (up to 99.3% under our conditions). [Display omitted] The accumulation of non-degradable microplastics (MPs) originated from the mass production and huge consumption of plastics of modern industry in the water environment has resulted in severe pollution problems globally. Herein, we report for the first time the preparation of holey Ti 3 C 2 Tx (h-Ti 3 C 2 Tx) membranes obtained by etching Co 3 O 4 nanoparticles embedded on Ti 3 C 2 Tx nanosheets followed by simple vacuum filtration using polymeric membranes as supporting matrix for efficient removal of MPs from wastewater. The h-Ti 3 C 2 Tx nanosheets exhibit a planar porous structure which present nano-holes with an average hole-size of 25 nm in diameter, which facilitated the construction of membranes with better water flux for the separation of MPs. Using fluorescent PS (FP) microspheres of different diameters as microplastic models, the obtained h-Ti 3 C 2 Tx membranes exhibited extremely high MPs removal performance (up to 99.3% under our conditions). Moreover, a large water flux of 196.7 L h−1 m−2 k Pa−1 can be obtained, which can compete or be larger than that of most of the membranes composed of untreated two-dimension nanomaterials. Due to the physicochemical stability, tremendous large water reflux, and the high MPs removal efficiency of h-Ti 3 C 2 Tx membranes, there may be a great potential for practical applications in the separation and removal of various contaminants such as MPs or suspended solids from water. [ABSTRACT FROM AUTHOR]

Cathodic oxygen reduction reaction is a decisive factor for fuel cell. In this work, for the first time, we demonstrated the synthesis of N -doped carbon hollow spheres derived from conjugated microporous polymers. The resulting sample remained the inherent porosity and N component with hollow spherical morphology, which exhibits excellent ORR performance with higher limiting current density and stability than that of commercial Pt/C catalyst in alkaline solution. [Display omitted] The exploitation non-precious or metal-free electrocatalysts of oxygen reduction reaction (ORR) is of significance for construction of next-generation fuel cells. In this work, hollow-spherical conjugated microporous polymers (CMPs) comprising porphyrin units were synthesized as precursors to prepare N -doping porous carbon spheres (CMP-NP-x) by a direct pyrolysis method. The as-resulted CMP-NP-x exhibited spherical morphology with hollow structure similar to that of CMPs precursors. The BET surface area of CMP-NP-x can be tailored by the pyrolysis temperature varying from 868 m2 g−1 to 1118 m2 g−1. According to XPS analysis, the pyrrolic N content in the sample decreased but the graphitic N and pyridinic N increased with increasing of the pyrolysis temperature from 800 °C to 1000 °C. Taking advantages of porous structure with large accessible surface areas and N species active sites, the resulting CMP-NP-x showed superior ORR activity and methanol tolerance to commercial Pt/C catalyst. In particular, CMP-NP-900 possesses the highest onset potential (0.930 V), half-wave potential (0.857 V) and limiting current density of 4.45 mA cm−2, compared with Pt/C catalyst and other samples, making it a promising metal-free catalyst superior to commercial Pt/C catalyst in alkalic condition. [ABSTRACT FROM AUTHOR]

[Display omitted] The development of an environmental-friendly thermal insulation and flame retardant material has attracted widespread attention in modern architecture. In this work, a kind of novel aerogel composites were prepared by incorporation of Mg(OH) 2 coated hollow glass microspheres (HGM) into chitosan (CSA) matrix and then cross-linking by glutaraldehyde (abbreviated as CSA-HGM-Mg(OH) 2). The as-prepared composite aerogel exhibits vertical directional channel with high porosity and excellent thermal insulation with a low thermal conductivity of 0.035 W m−1 k−1. Besides, it shows excellent flame retardancy with a high limit oxygen index (LOI) value up to 50.8, which is one of the highest values among the most of flame retardants reported previously. Also, a very low peak heat release rate (pHRR) of 24.12 kW m−2 was obtained which makes the aerogel composite reaching UL-94 V-0 rating. Such results may be attributed to a synergy effect by combination of its abundantly porous structure derived from HGM to give a better thermal insulation and excellent nonflammability of CSA and Mg(OH) 2 to offer a superior flame retardancy. Taking advantages of its high mechanical strength, low cost materials, simple and scalable preparation method, CSA-HGM-Mg(OH) 2 aerogel composites may hold great potential for future thermal insulation and flame retardant applications. [ABSTRACT FROM AUTHOR]

The development of functional materials with better flame-retardant and thermal insulation properties has attracted considerable attention for energy storage applications in modern society. Here, we describe a facile approach for the preparation of conjugated microporous polymer hollow spheres (CMP-HSs) by using SiO 2 nanoparticles as a template via the Sonogashira-Hagihara cross-coupling reaction. The as-synthesized CMP-HSs have good thermal stability with a thermal decomposition temperature of up to 281 °C, high porosity (the BET specific surface area is measured to be approximately 666 m2 g−1) along with lipophilic and hydrophobic characteristics. To further improve their flame retardancy, CMP-HSs were treated with dimethyl phosphonate (DMMP) though an immersion method to prepare the CMP-HSs composite (CMP-HSs-DMMP) flame-retardants. By introducing CMP-HSs-DMMP into the epoxy resin (EP) matrix, the as-prepared EP composites showed excellent flame-retardant properties, e.g., the peak heat release rate (pHRR) and total heat release (THR) value of EP composites containing only 0.2% CMP-HSs-DMMP flame-retardant were 650.9 kW m−2 and 79.4 MJ m−2 respectively, in the range of 0 °C − 650 °C, which are 19.6 ± 2% and 19.1 ± 5% lower than that of pure EP within the same temperature range. Considering the significant enhancement of its flame retardancy with only a slight dosage of CMP-HSs-DMMP, such CMP hollow sphere-based flame-retardant composites may have great potential as functional bulk materials or coatings in a variety of fireproofing applications. [ABSTRACT FROM AUTHOR]

• Catalytic partial oxidation (CPOX) processing experimentally investigated to use Methane in SOFC. • Reynolds number effects on electrochemical performance of the SOFCs. • Carbon deposition prevented by utilizing oxygen with methane in favorable operating conditions. • Investigation of the carbon deposition through the NiO-YSZ anode by EDAX and SEM. The development of high-performance non-precious metal electrocatalysts is of great importance for construction of next generation fuel cells. Herein, we report for the first time the creation of new metal-free porous carbon framework catalysts derived from N -rich hypercrosslinked polymers (HCPs) using pyrrole as building blocks for oxygen reduction reaction (ORR) (denoted as PCF-HCPs). The PCF-HCPs obtained at the pyrolysis temperature of 900 °C (PCF-HCP-900), displayed outstanding catalytic activity towards the ORR compared with other PCF-HCPs pyrolysis temperature. Due to PCF-HCP-900 with large specific surface, excellent porosity and, importantly, exposed active sites caused by N doping with high density, the catalysts exhibited outstanding ORR activity in alkaline medium, i.e., the PCF-HCP-900 yielded a half-wave potential of 0.84 V, which was 10 mV higher than that of the state of-the-art Pt/C catalyst (0.83 V), and onset potential of 0.95 V (vs. RHE), a high diffusion limiting current density of 4.8 mA cm−2, better methanol tolerance and long-term stability (2 mV negative shift after 3000 potential cycles) than commercial Pt/C. Furthermore, PCF-HCP-900 shows a favorable 4-electron transfer process (n ≈ 3.96) and lower H 2 O 2 yield. Based on these merits, the PCF-HCP-900 may open a new possibility for design of ORR metal-free catalyst of fuel-cell technologies. [ABSTRACT FROM AUTHOR]