The rapid development of electronic technology promotes the evolution of electronic devices towards integration, miniaturization and densification. The heat dissipation problem caused by over-heating accumulation and electromagnetic radiation will threat the reliability and life time of these devices, and even cause failure. Thus, it is desirable to prepare highly thermally conducive composites with electromagnetic shielding effect. Herein, the three-dimensional (3D) CNTs networks were grown in-situ on the foamed nickel by synergistic bimetallic catalysis to construct thermally conductive interconnected network, filling with epoxy resin (EP) to obtain the Fe-Ni@CNTs/EP composites. The foamed nickel not only works as the supported skeletons of the composites, but also accelerates the synthesis of CNTs networks via bimetallic catalysis of Fe and Ni. The resultant Fe-Ni@CNTs/ EP composites exhibit high in-plane and out-of-plane thermal conductivities of 0.83 and 1.23 W/(m center dot K), respectively. Moreover, the as-prepared Fe-Ni@CNTs/EP composites show the electromagnetic shielding efficiency of more than 37 dB in the X-band and a large alternating current (AC) conductivity of 2.2 & times; 10- 3 S/cm at 0-107 Hz. Besides, the average thermal expansion coefficient of Fe-Ni@CNTs/EP is 127.3 ppm/degrees C in the range of 20-190 degrees C, demonstrating excellent thermal stability. The work provides a new strategy for constructing efficient thermally conductive networks and has prospects in the fields of electronic, chip packaging and semiconductor devices.

The solar-driven evaporation of water is deemed as the most promising technology for producing freshwater. However, the complex recalcitrant organic pollutants will contaminate and even shorten the life time of the photothermal materials. Herein, the vertically aligned Fe-doping carbon nanosheets (Fe/CNSs) aerogel were constructed to produce fresh-water from sewage. The porous vertically oriented structure was built by using melem as carbon resource via the ice-templating method. The carbon nanosheets were grown in-situ on the vertically aligned skeletons of melem under the catalysis of ferrocene. The obtained Fe/CNSs composites exhibit excellent hydrophilicity and sunlight absorption as high as 97.3%, resulting in an outstanding solar evaporation efficiency of 91.7% and completely degradation of organic pollutants (methylene blue, methyl orange, tetracycline hydrochloride and bisphenol A) under 1 sun irradiation (1 kW m-2) synergistically. The Fe atoms doped in the carbon nanosheets, which accelerate the generation and transportation of radicals via the photo-Fenton, leading to a rapid degradation efficiency and address the issue of Fe recycling. This work provides a promising strategy for treating the wastewater containing refractory pollutants, such as industrial, dyeing and pharmaceutical wastewaters.

ABSTRACT Order‐aligned structures of thermally conductive fillers in the matrix are of great importance for the highly effective thermal interface materials (TIMs) in the fields of electronic devices, semiconductors, and electronic packaging. However, achieving high thermal conductivity via constructing ordered structures with low filler content remains challenging. Here, we construct vertically aligned Silicon nitride (Si 3 N 4 ) whiskers covered by the in situ growth of carbon nanotubes (CNTs) to form an efficient thermal conductive network. Owing to the successful construction of interconnected structures via thermally conductive Si 3 N 4 whiskers and CNTs, the Si 3 N 4 @CNTs/EP composite with filler content of 8.31 vol% exhibits high out‐of‐plane thermal conductivity of 1.54 W m −1 K −1 and excellent electrical insulation. This finding provides a promising strategy to design high‐performance thermal conductive composites for TIMs in high‐power devices.

Although the solar interfacial evaporation technology with the advantages of outstanding photothermal conversion, easy availability and high freshwater production, their photothermal materials still face the problem of contaminated by the organic pollutants in the raw waters such as sewage and natural water. Herein, we present a vertically oriented hierarchical C/TiO2 nanotubes with bifunction of photocatalytic degradation of pollutants and freshwater production via photothermal effect synchronously. The carbon nanoparticles of the hierarchical C/TiO2 nanotubes not only broaden the range of sunlight absorption to accelerate the water evaporation, but also reduced the recombination of electron-hole significantly to improve the photocatalytic efficiency. Meanwhile, the excellent water transportation via unique arranged arrays vertically, the abundant active sites derived from hierarchical structure, the vertical oriented C/TiO2 nanotubes exhibit a large solar-driven water evaporation rate of 1.59 kg m- 2 h- 1 and the methyl orange (MO) photodegradation efficiency of 92.9 % for the underneath sewage under 1 sun illumination synchronously. These findings have great potential applications in solarpowered production freshwater from wastewater and natural waters such as rain and river water.

Water scarcity and pollution are the challenges most countries face around the world, especially the large amount of organic wastewater. Solar-driven evaporation is an environmentally friendly and high-performance technology of freshwater production. However, photothermal materials fail when the water includes complex recalcitrant pollutants such as tetracycline hydrochloride (HCL-TC) and bisphenol A (BPA). Here, Fe@carbon nanotube (Fe@CNT) arrays were prepared in situ by using acetonitrile as the carbon source and ferrocene as the catalyst, followed by further solar-driven water evaporation and photo-Fenton catalytic degradation of organic pollutants synergistically. Owing to the Fenton effect and excellent solar absorption, Fe@CNTs accelerate the separation of photogeneration electron-hole pairs to improve the degradation of organic pollution and production of freshwater. Therefore, the Fe@CNT layers show outstanding solar absorption and hydrophilicity, resulting in a high solar evaporation efficiency of 94%. Meanwhile, the degradation efficiencies of organic pollutants (methylene blue, HCL-TC, and BPA) are more than 99% due to the synergistic effect of photothermal and photo-Fenton-catalysis effects. This work provides a promising strategy for the treatment of organic wastewater in an environmentally friendly way.

Efficient heat dissipation is an important technology to address the issues of overheating and increasing heat flux density for high-density integrated electronic devices toward miniaturization, multifunctionality, and high integration. Carbon nanotubes (CNTs) are considered as an ideal thermally conductive filler of polymeric encapsulation owing to its excellent thermal conductivity and unique linear structure but suffer from the random arrangement in the composites and extremely low thermal conductivity of the polymeric matrix. Here, we report vertically aligned carbon nanotubes (VACNTs) grown in situ by chemical vapor deposition, which were modified by polyethylene polyamine and covered with poly(vinyl alcohol) (PVA) to form the m-VACNTs/PVA thermally conductive composite film. The out-of-plane thermal conductivity of the m-VACNTs/PVA film reaches as high as 14.9 W m-1 K-1, which is approximately 53 times that of a pure PVA film. In addition, the m-VACNTs/PVA composites have excellent electrical conductivity and an outstanding electromagnetic shielding effect. This study provides a promising strategy for design of advanced composites with high thermal conductivity in the vertical direction.

Polymer thermally conductive composites have emerged as ideal materials to address the issue of heat accumulation in various electrical devices. However, the practical application of thermally conductive composites often requires low filler content with multifunctional properties to meet the rapid development of electronic technology. Herein, highly oriented carbon nanotubes (O-CNTs) were grown in situ on vertically aligned melem skeletons by ice templating and high-temperature catalytic methods. The ordered CNTs were constructed by a cross-linking network in the matrix of epoxy (EP) for efficient heat transport pathways. The oriented O-CNTs/EP composite exhibits outstanding out-of-plane and in-plane thermal conductivities as 2.36 and 1.20 W/(mK) with a CNT content of 4 wt %, respectively. The O-CNTs/EP composite also shows an excellent electromagnetic shielding effect of over 30 dB in the range of 8-40 GHz. This work provides a promising strategy for the construction of high-performance composites with advanced heat dissipation in thermal management materials.

The highly efficient degradation and purification of organic pollutants in wastewater by photocatalysis is still challenging. In this study, a piezoelectric potential-activated interfacial electric field (IEF) was constructed to endow BiFeO3@BaTiO3 (BFO@BTO) heterojunction with the ability to serve as a round-the-clock photocatalyst for polluted water remediation. BFO@BTO heterojunction is composed of BiFeO3 nanoparticles decorated on the surface of BaTiO3 nanorods, which shortens the carrier migration path. More importantly, the IEF can be activated and reconstructed under ultrasonic wave irradiation, leading to a lower potential barrier and enhanced separation efficiency for photogenerated carriers. The degradation rate constant k value of BFO@BTO heterojunction reached 0.038 min−1, which was 1.9 and 7.0 times greater than that of piezocatalysis and photocatalysis alone, respectively. It also exhibited excellent stability in three light‒dark cycles for high concentrations (25 mg·L−1) of rhodamine B (RhB) and tetracycline hydrochloride (TC). This study provides a promising strategy for designing highly active photoassisted piezocatalysts for environmental energy utilization and round-the-clock catalysis.

Solar-driven interfacial evaporation has emerged as an efficient and sustainable way to generate freshwater from seawater to address the crisis of drinkable water. Though rational designs of photothermal materials and structures are essential to the interfacial solar evaporation process, the salt accumulation remains a challenge to the long-term operation of seawater desalination. Here, we report a high-yield and low-cost natural sphagnum as solar steam generator with ultra-fast water transportation, unique microstructure to prevent salting out, and high evaporation rates. The carbonized sphagnum based photothermal evaporator exhibits a strong broad-band light absorption (>97.0 %). During the solar steam generation, a high evaporation rate of 3.53 kg m(- 2) h-1 was achieved under 1.0 sun illumination. More significantly, the 3D sphagnum evaporator shows excellent selective filtration of salt ions and cycling stability in actual sea water even high salinity solution (10 wt.% NaCl) for 7 days. This work provides an environmentally friendly and cost-effective photothermal material for large-scale seawater desalination, and treatment of waste water with high ions concentration.

Solar-driven water evaporation is a promising technology of freshwater production to address the water scarcity. However, the photothermal material and the distilled water would be contaminated in the evaporation of wastewater including organic pollutants. In this work, MOF-derived C/TiO2 composites (carbonized UiO-66-NH2 (Ti)) with simultaneous photothermal and photocatalytic functions are designed for producing freshwater from sewage. With advantageous features of porous structure with large specific area, excellent sunlight absorption and super-hydrophilicity, the carbonized UiO-66-NH2 (Ti) layer exhibits high water evaporation efficiency of 94% under 1.0 sun irradiation. Meanwhile, the layer can simultaneously decompose the organic pollutants with degradation efficiency of 92.7% in the underlying water during solar-driven water evaporation. This bifunctional material will provide a new approach for solar-driven water evaporation and photocatalytic degradation of organic pollutant synergistically.

Series of polymethylmethacrylate (PMMA)/recycled polyethylene terephthalate (RPET) blends were prepared by melt blending. Effect of PMMA content on the crystallization behavior and thermal conductivity of the blends was intensively investigated. The non-isothermal crystallization suggested that PMMA showed an inhibitory effect on PET's crystallization process. Enthalpy transformation method (ETM) and a four-parameter model (TPM) were jointly used to learn the thermally conductive behaviors of the blends. As the PMMA content increased, the thermal conductivities of the blends were also enhanced, which could be related to the formation of PMMA network structure in the prepared blends and subsequently verified via SEM observation on the cross-sectional microstructures. The present study will be practically significant to further expansion of the application fields for RPET.

Solar-driven interfacial evaporation has emerged as an efficient and sustainable way to generate freshwater from seawater to address the crisis of drinkable water. Though rational designs of photothermal materials and structures are essential to the interfacial solar evaporation process, the salt accumulation remains a challenge to the long-term operation of seawater desalination. Here, we report a high-yield and low-cost natural sphagnum as solar steam generator with ultra-fast water transportation, unique microstructure to prevent salting out, and high evaporation rates. The carbonized sphagnum based photothermal evaporator exhibits a strong broad-band light absorption (>97.0%). During the solar steam generation, a high evaporation rate of 3.53 kg m -2 h -1 was achieved under 1.0 sun illumination. More significantly, the 3D sphagnum evaporator shows excellent salt-resistant performance and cycling stability in actual sea water even high salinity solution (10 wt.% NaCl) for 7 days. This work provides an environmentally friendly and cost-effective photothermal material for large-scale seawater desalination, and treatment of waste water with high ions concentration.

In this work, polymethyl methacrylate (PMMA) composites modified with diethylaluminum phosphonate (ADP) and epoxy resin (EP) as flame retardant and toughener, respectively, were prepared via solution method for improvement on both flame retardancy and toughening purposes. The effects of ADP and EP loadings on the viscoelastic, flame retardant and thermomechanical behaviors of the resultant composites were intensively investigated using rheometer, CONE calorimetry, oxygen index (LOI) and dynamic mechanical thermal analysis (DMTA), respectively. Heat flux complexity was obviously displayed when ADP and EP loadings increased. DMTA result showed that the increase of the modulus of the composites was primarily due to an interpenetrating polymer network (IPN) formed by the addition of EP, and the tensile properties were found to be greatly improved. In addition, our study also showed that at an ADP loading of 28% the maximum heat release rate (pHRR) of composites decreased by 63% as compared to neat PMMA with increase by 88% in LOI and V-0 grade in UL-94 test achieved. The composites prepared in this study bore excellent fire performance together with desired toughness, and the current work thus has practical significance for further expanding the application range of PMMA composites.

随着经济社会的高速发展,水资源短缺、环境污染、能源危机等是当前世界各国面临的难题.利用丰富的太阳能从海水、污水中蒸馏分离获得纯净水,是一种绿色、可持续的解决方案.然而,传统的太阳能蒸馏提纯原理是加热整体待分离液体,光热转换效率只能达到30％～45％,并且需要昂贵的设备和频繁的维护,这些因素极大地限制了太阳能在水净化领域中的实际应用.近年来出现的界面太阳能蒸发技术通过高效的光热转换材料将吸收的太阳能局限在蒸发层表面,大幅提高了光热转换效率,是一种高效、低成本、环保的水净化技术,在海水淡化、蒸馏分离、发电等领域具有广阔的应用前景,被认为是未来解决水资源危机的一种潜在策略.本文介绍了界面太阳能蒸发技术中的光热转换机理,简述了光热转换材料、蒸发器结构设计和热能工程管理在太阳能蒸发技术中取得的进展,概述了界面太阳能蒸发技术的应用研究现状,包括海水淡化、污水处理、太阳能蒸馏-发电联产、灭菌以及其他能源转换应用等,总结了当前该技术在实际应用中遇到的瓶颈问题,并展望了界面太阳能蒸发技术的发展趋势.界面太阳能蒸发技术对解决水资源短缺和能源危机具有重要的意义.

Lithium-ion batteries (LIBs) have attracted more and more attention in recent years because of their renewable, clean energy and high-cost performance. Polyvinylidene fluoride (PVDF) and polymethyl methacrylate (PMMA) were expected to be used in the preparation of LIB separator due to their excellent comprehensive properties. In this work, a series of PVDF/PMMA LIB separators were prepared by thermally-induced phase separation (TIPS), which is a simple method of fabricating microporous films. In order to improve the comprehensive performance, SiO2 was adopted to modify the composite films with various filling proportions by solution method. Results of DSC and XRD tests showed that SiO2 nanoparticles could significantly reduce the crystallinity of the films, but hardly changed the morphology of PVDF. With an increase in SiO2 content, both porosity and electrolyte uptake rate for the composite films increased, but an excessive loading of SiO2 tended to agglomerate inside the films. The porosity and electrolyte uptake rate for composite film containing 3% SiO2 were found to be the highest. As SiO2 loading increased, both first charge–discharge capacity and efficiency of the composite films were enhanced with the discharge cycle stability enhanced simultaneously. When 3% SiO2 was incorporated, the PVDF/PMMA/SiO2 composite film displayed the best comprehensive performance of the battery among all film samples examined. This study presents a facile way of manufacturing LIB separators with relatively ideal overall battery performance.

Solar-driven interfacial evaporation has emerged as an efficient and sustainable way to generate freshwater from seawater to address the crisis of drinkable water. Though rational designs of photothermal materials and structures are essential to the interfacial solar vaporization process, the salt accumulation remains a challenge to the long-term operation of seawater desalination. Here, we report a high-yield and low-cost natural sphagnum as solar steam generator with ultra-fast water transportation, unique microstructure to prevent salting out, and high evaporation rates. The carbonized sphagnum based photothermal evaporator exhibits a strong broad-band light absorption (>97.0%). During the solar steam generation, a high evaporation rate of 3.53 kg m -2 h -1 was achieved under 1.0 sun illumination. More significantly, the 3D sphagnum evaporator shows excellent salt-resistant performance and cycling stability in actual sea water even high salinity solution (10 wt.% NaCl). This work provides an environmentally friendly and cost-effective photothermal material for water purification field such as seawater desalination, waste water treatment and so on.

AbstractIn this work, epoxy (EP) resin composites with “point‐surface” heterostructures constructed by hybrid fillers of Ni particles and graphene nanosheets (GNPs) are prepared via a blending method under magnetic field. Effects of filler content and magnetic orientation on dielectric, thermally and electrically conductive, and thermomechanical properties of the resultant composites are investigated. The findings disclose that the synergistic effect of hybrid fillers and the magnetic orientation result in the formation of a complex heterogeneous network structure, significantly improving both thermal and electrical conductivities. From the temperature distribution analysis, it is the construction of the heterogeneous network that improves the thermally conductive and thermomechanical properties. Sample Y4 (containing 28 wt% Ni and 2 wt% GNP) displays an average heating rate (AHR) of 152.4 °C min−1and has an out‐of‐plane thermal conductivity of 0.930 W m−1 K−1(267.6% higher than that of neat EP). The infrared thermal imaging (ITI) together with SEM observations further confirms that the Ni chains in situ formed under a magnetic field are responsible for the improved composite's thermal conductivity and thermal management capability, which make it potentially applicable for 3D packaging materials in power‐intensive electronic components.

Solar-driven evaporation of water is a sustainable and promising technology for addressing the crisis of clean water. Herein, novel vertically arranged carbon nanotube (V-CNT) aerogels with a tree branch structure is facilely synthesized through an ice templating method. The V-CNT-based photothermal evaporator exhibits efficient broadband light trapping and super-hydrophilicity. Owing to the unique structure and ultrafast water transportation, a high evaporation rate of 3.26 kg m-2 h-1 was achieved by the three-dimensional V-CNT-based evaporator under a solar illumination of 1 kW m-2. More significantly, the V-CNT shows excellent recycling stability and salt-resistant performance in seawater and may provide a novel strategy to the practical sustainable technique of water purification applications.

In this study, a series of poly(methyl methacrylate) (PMMA) copolymer films were prepared via solution polymerization of methyl methacrylate (MMA) with butyl acrylate (BA) and lauryl methacrylate (LMA) as monomers. Mechanical properties, hydrophobic properties, and optical properties of the films were intensively investigated. The rheological results showed that the fluidity of the copolymer was considerably enhanced. When the monomer ratio of MMA:BA:LMA was 100:30:10, the copolymer film S4 showed the best overall performance with perfect optical transparency maintained. The results of the dynamic mechanical and thermal analysis suggested that the glass transition temperature (TO moved towards lower temperature, with enhanced ductility of the PMMA films. A large number of yield folds and crazes appeared on the cross-sectional surface of copolymer films through morphological observations, displaying the obvious characteristics of toughness fracture and obeying the energy dissipation mechanism of cracks shear band. The present study provided a facile way of preparing PMMA films with high toughness and light transmittance by appropriate selection of the monomers, which will be of practical significance for further studies on the replacement of triacetyl cellulose as a support film of polarizers.

Solar vapor generation is a sustainable and cost‐effective approach to addressing the issue of water shortage. However, the challenges of solar steam generation still exist for achieving a high evaporation efficiency combined with long‐term stability in the wastewater containing heavy metal ions and wide degrees of acidity and alkalinity (pH = 1–14). Herein, polypyrrole (PPy) loading on the N,S‐doped graphene oxide (N,S‐GO) foam is used for high‐efficiency solar evaporation of treating wastewater. With the advantages of excellent broadband solar absorption ( >97%), extremely low emissivity (0.70), and outstanding hydrophilicity, the N,S‐GO/PPy foam achieves a high evaporation efficiency of 90.5% under 1 sun illumination. More notably, the N,S‐GO/PPy foam has strong adsorption of heavy metal ions (Fe 3+ , Cu 2+ , and Cr 6+ ) for treating wastewater synchronously evaporates at higher efficiencies of 94.7–98.4%. Interestingly, the high‐toxicity Cr 6+ can be reduced to low‐toxicity Cr 3+ effectively by the synergistic effect of N,S‐GO and PPy. In addition, the N,S‐GO foam shows a better long‐term resistance of acidity and alkalinity for 45 days. A new insight is offered into high‐efficiency solar evaporation for treating wastewater and water purification.