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Polymer dielectrics have been widely employed in pulsed power systems, but their applications are severely restricted by the low energy density. Incorporating core‐shell nanofillers is one promising strategy to enhance the energy density of polymer dielectrics. Nowadays, core‐shell nanofillers are mainly prepared via chemical coating strategies, which always involve complex chemical synthesis procedures. Herein, a unique physical coating strategy is developed to prepare core‐shell TiO2@Au nanofibers consisting of monodispersed Au nanoparticles homogeneously anchored on the TiO2 nanofibers. Interestingly, the TiO2@Au nanofibers show outstanding dielectric energy storage boosting capability. Specifically, with merely introducing 0.1 wt.% TiO2@Au nanofillers, the TiO2@Au/PVDF composite exhibits a substantially enhanced breakdown strength of 749 MV m−1, which reaches 152.8% of PVDF. Meanwhile, a high dielectric constant of 10.2 (114.1% of PVDF) is obtained. Consequently, an ultrahigh energy density of 18.6 J cm−3, which is 250.1% of PVDF, is achieved. It is further revealed that the significant energy storage boosting effect is originated from the Coulomb blockade and micro‐capacitor effects of the TiO2@Au nanofibers. This work establishes a unique paradigm for the facile preparation of core‐shell nanomaterials, which have huge potential for both dielectric energy storage and other functional nanocomposites. [ABSTRACT FROM AUTHOR]

The development of magnetocaloric materials with a significantly enhanced volumetric cooling capability is highly desirable for the application of adiabatic demagnetization refrigerators in confined spatial environments. Here, the thermodynamic characteristics of a magnetically frustrated spin‐7/2 Gd9.33[SiO4]6O2 is presented, which exhibits strongly correlated spin disorder below ≈1.5 K. A quantitative model is proposed to describe the magnetization results by incorporating nearest‐neighbor Heisenberg antiferromagnetic and dipolar interactions. Remarkably, the recorded magnetocaloric responses are unprecedentedly large and applicable below 1.0 K. It is proposed that the S = 7/2 spin liquids serve as versatile platforms for investigating high‐performance magnetocaloric materials in the sub‐kelvin regime, particularly those exhibiting a superior cooling power per unit volume. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are considered one of the most effective methods for harvesting irregular and low‐frequency raindrop energy. In this work, molybdenum selenide (MoSe2) nanosheets act as intermediate layers for improving droplet‐based TENG performance. Consequently, without surface etching process, the short‐circuit current (Isc) and open‐circuit voltage (Voc) of the TENG can reach as high as 1.2 mA and 120 V, respectively. Furthermore, precise energy analysis based on an optimization model for input energy calculation is carried out, allowing conversion efficiency to be calculated under diverse conditions. Finally, an all‐solid supercapacitor is fabricated for integration with the TENG. An intelligent wireless sensing system, powered by the integrated TENG and capacitor, is demonstrated for monitoring environmental information. This study provides new insights into intermediate‐layer materials' selection and action mechanisms. It fills a gap in the research on a precise model of theoretical energy conversion efficiency calculation. The integrated devices and sensing applications will provide strategies for creating smart cities. [ABSTRACT FROM AUTHOR]

Copper ions (Cu2+) pollution poses a serious threat to Marine ecology and fisheries, but the online detection is difficult due to seawater interference. Herein, photo‐assisted barrier effect is introduced into electrochemical detection as a driver to generate electrochemical response. The n–n junction barrier exhibits excellent adjusting effect on electrochemical response under photoexcitation and could effectively drive electrochemical response by Cu2+ adsorption. The prepared Ti/TiO2/In2O3/Chitosan wire is used for direct Cu2+ detection, and the trace detection with the low detection limit (59.08 nm) is achieved. The strong interference of seawater is resisted effectively by using photo‐assisted barrier effect, and the good recovery rate (94.9–107.1%) in the actual seawater detection make it promising for practical applications. It is a new approach to develop electrochemical sensors by using photo‐assisted barrier effect to resist interference. [ABSTRACT FROM AUTHOR]

Membrane technology provides a reliable and powerful solution to combat the global water crisis by producing fresh water through sustainable desalination. However, the decline in system performance due to membrane biofouling is a limitation and significant efforts have been made to explore fouling control mechanisms and develop simple methods to inhibit or eliminate membrane fouling. Nanotechnology has increased the number of options for the development of antibiofouling membranes by incorporating nanoparticles within the polyamide layer to produce a thin‐film nanocomposite (TFN) structure. This review presents recent advances in the preparation of antifouling TFN membranes and incorporation of different nanoparticles into the design. The review also discusses the strategies and mechanisms for reducing membrane fouling and proposes a future outlook for the field. [ABSTRACT FROM AUTHOR]

In order to refine microstructure and improve mechanical properties, size of lamellar colonies and reinforced phase, distribution of elements, and microhardness with different solidification rates were studied by rapid solidification. Results show that microstructure morphology changes from equiaxed grain to granulated dendrites after rapid solidification. When speed of revolution increases, size of lamellar colonies decreases from 53.5 to 16.9 μm and length of TiB particles decreases from 60.1 to 20.4 μm. The B2 phase exists in lamellar colonies and at the boundary of lamellar colonies before rapid solidification and forms in lamellar colonies after rapid solidification. An increase in solidification rate increases degree of supercooling to increase number of nucleation particles which form before solidification front. The β phase incompletely transforms to the α phase and is retained in α phase after rapid solidification. The microstructure does not have enough time to transform completely and high‐temperature microstructure is retained at a higher cooling rate. Test results show that microhardness increases from 453 to 562 HV when speed of revolution increases from 0 to 800 rpm. Improvement of microhardness results from solution strengthening of Nb, Cr, and V, grain refinement strengthening and reduction of the reinforced phase of TiB. [ABSTRACT FROM AUTHOR]

As the environment deteriorates, recycling of solid waste has become increasingly important. This study aimed to optimize the use of the Fe2O3, SiO2, and CaO components in coal fly ash and to convert coal fly ash into stable porous Al2TiO5‐mullite (AT–M) composite ceramic by sintering with AlOOH and TiO2 additives at high temperatures. The phase composition, microstructure, apparent porosity, corrosion resistance, and mechanical properties of porous AT–M composite ceramics were systematically investigated. Results indicated that the sintered samples exhibited pore size distributions within the 0.16‐2.9 μm, apparent porosities of approximately 52.8%, and flexural strength of 29.6 MPa. Corrosion resistance data revealed quality losses in the aqueous NaOH and H2SO4 solutions for 10 hours at 0.42% and 2.19%, respectively. After corrosion for 8 hours, the average flexural strength of the samples remained at 21.6 ± 0.53 and 20.84 ± 0.6 MPa, respectively. These findings show that these porous AT–M ceramics may provide enhanced corrosion resistance under alkaline conditions. The porous AT–M composite ceramics may fabricate high‐performance composite membrane supports for the high temperature flue gas filtration. [ABSTRACT FROM AUTHOR]

Abstract: Porous alumina ceramics were fabricated by starch consolidation casting using corn starch as a curing agent while their microstructure, mechanical properties, pore size distribution, and corrosion resistance were examined. Results showed that the porous alumina ceramics with the flexural strength of about 44.31MPa, apparent porosity of about 47.67% and pore size distribution in the range of 1‐4 μm could be obtained with 3wt% SiO2 and 3wt% MgO additives. Corrosion resistance results showed mass losses: hot H2SO4 solution and NaOH solution for 10 hours were 0.77% and 2.19%, which showed that these porous alumina ceramics may offer better corrosion resistance in acidic conditions. [ABSTRACT FROM AUTHOR]

Herein, ultradispersed In2S3 nanoparticle (NP)/TiO2 nanobelt (NB) heterostructures with an intimate interfacial coupling effect are synthesized from the consideration of combining the visible/near-infrared photoabsorption property of In2S3 with the excellent UV photocatalytic property of TiO2. In this process, the 1D TiO2 NBs not only perform as the support to form the heterostructure, but are also employed as a dispersant to confine the aggregation of In2S3 NPs. As expected, the obtained In2S3 NP/TiO2 NB heterostructure gives rise to a prominently strong optical absorption in the full solar region of 300-1800 nm, and thus displays a desired photocatalytic degradation of tetracycline in full utilization of all solar energy, compared with that of pristine In2S3 and TiO2. Besides, the In2S3 NP/TiO2 NB heterostructure photocatalysts have no selectivity and can effectively degrade other different kinds of organic pollutants, including cationic dyes (methyl blue and rhodamine B) and colorless chemical pollutants (phenol and salicylic acid). The exceptional photocatalytic enhancement is due to the synergistic interactions of heterojunction with the strong interfacial coupling effect, the In2S3 extended light absorption, efficient photogenerated e−/h+ pair separation, and fully exposed reactive sites induced by uniform packing of the ultrasmall In2S3. [ABSTRACT FROM AUTHOR]

Recently, near-infrared light (NIR) photocatalysts, such as up-converting materials, Bi2WO6, Cu2(OH)PO4, and carbon quantum dots, have been found and are attracting attention for environmental cleaning and energy conversion, because NIR light constitutes nearly half of the energy output. However, the photocatalytic efficiency is low for these new types of NIR photocatalysts, which has limited their widespread application owing to their insufficient NIR-light absorption. In this work, we use gold (Au) nanorods to enhance the NIR-light absorption of Bi2WO6, a typical visible and novel NIR-light photocatalyst, thus the enhancement of its NIR-light photocatalytic and photoelectrochemical properties are achieved. This can be attributed to the surface plasmon resonance (SPR) effects and wide-range NIR light harvesting of the Au nanorods. The present work provides key guidelines for the improvement of NIR-light photocatalysts and could also help design and prepare novel photocatalysts. [ABSTRACT FROM AUTHOR]

Porous TiO2 films decorated with Bi2O3 nanoparticles are fabricated via alkali-hydrothermal of titanium (Ti) plate by varying the reaction time. The amorphous TiO2 is transformed into anatase after annealing the films at 500°C in air. The p-type Bi2O3 nanoparticles are successfully assembled on the surface of porous n-type TiO2 films through the ultrasonic-assisted successive ionic layer adsorption and reaction (SILAR) technique to form Bi2O3/TiO2 nanostructure by the two cycles. The obtained Bi2O3/TiO2 films are consisted of a well-ordered and uniform porous structure with an average pore diameter of about 100-200 nm containing homogeneously dispersed Bi2O3 nanoparticles of ~5 nm diameter. Moreover, the resultant composites present excellent photocatalytic performance toward methyl blue (MB) degradation under UV and visible light irradiation, which could be mainly ascribed to the enhanced light adsorption capacity of unique composite structure and the formation of p- n heterojunctions in the porous Bi2O3/TiO2 films. This research is helpful to design and construct the highly efficient heterogeneous semiconductor photocatalysts. [ABSTRACT FROM AUTHOR]

Single crystal of organolead trihalide perovskite (CH3NH3PbI3) is proved to be one of the most promising semiconductor materials. Growing large size and high quality CH3NH3PbI3 single crystals is urgently demanded by photoelectric device applications. However, the growth mechanism in microscopic scale for CH3NH3PbI3 single crystal is still unrevealed. In this paper, we are focusing on observing surface structures on (100) facet of CH3NH3PbI3 single crystal via atomic force microscopy (AFM), especially surface structure conversion related to growth kinetics. The results reveal that the growth of (100) facet of CH3NH3PbI3 single crystal is dependent on bunching steps and step slope. The elemental steps, with step height about 0.45 nm, corresponded to half of the unit cell, are generated from screw dislocations when the growth rate is about 0.2 mm per hour. Elemental steps can bunch together and form bunching steps with growth rate of 0.5 mm per hour, in which only even numbers elementary steps are involved, suggesting even numbers elementary steps are stable than that of odd numbers. Additionally, in terms of the surface structures and solution stabilities, large size and high quality CH3NH3PbI3 single crystals were grown. [ABSTRACT FROM AUTHOR]

The bcc like structure of cubic bismuth phosphate (Bi13.1POδ) crystal, makes (111) facets hardly be exposed according to the Bravais rule. In this paper, we are focusing on the exposure of smooth (111) facets on cubic bismuth phosphate crystal, and particularly on the process of the smooth (111) facets transforming to stepped and coarse (111) facets by varying the growth conditions, such as the Bi: P ratio of the raw materials, pH values, EDTA concentrations, etc. The results revealed that lower Bi: P ratio was beneficial to smooth (111) facets and with a rise of Bi: P ratio, the (111) facets transformed from smooth surface to stepped and coarse surfaces. With a moderate Bi: P ratio and EDTA concentrations, novel facets with high index were derived on the (111) facets, which were deduced as (611) facets. Additionally, the growth mechanism of the process was summarized in terms of the growth units affected by the Bi: P ratio, pH values and the presence of EDTA. [ABSTRACT FROM AUTHOR]

Sulfate attack is one of the most important factors that lead to the performance deterioration of concrete materials. The progress of the sulfate diffusion depth in concrete is an important index that quantitatively characterizes the rate of concrete damage, cracking, and spalling due to sulfate attacks. The progress of the diffusion depth of concrete to sulfate attack is systematically investigated in this paper by both theoretical and experimental study. A newly time-varying model of the diffusion depth is developed, which has comprehensively considered a mass of parameter of complex environments for the first time. On this basis, a method is further proposed for effectively predicting the residual life of in-service concrete structures subject to sulfate attack. Integrating the data from the self-designed high-temperature dry-wet accelerated corrosion test and a large amount of experimental data reported in the existing literatures, the effectiveness and accuracy of the time-varying model of the diffusion depth by sulfates are finally verified. [ABSTRACT FROM AUTHOR]

Polymer dielectrics have broad applications in advanced electronics and power systems. However, they suffer from low energy density and poor breakdown performance at high temperatures, limiting their applications in high‐temperature environments. Herein, TiO2@Au@AlOx@Au nanofibers with double coulomb blockade nanolayers are obtained via a physical sputtering strategy to improve the high‐temperature energy storage performance of polyetherimide composites. Experimental studies and finite elemenet phase‐field simulations demonstrate that the double‐layer coulomb blockade effect and micro‐capacitor effect of Au nanoparticles synergistically enhance the breakdown strength and dielectric permittivity of polyetherimide composite at high temperatures. Notably, the composite exhibits ultra‐high discharged energy densities of 11.33 and 9.70 J cm−3 at 150 and 200 °C, respectively, along with high charge–discharge efficiencies of 93.4% and 84%, which far exceed that of the polymer nanocomposites reported so far. Furthermore, the composite exhibits excellent charge–discharge cycling performance (>50000 cycles at 400 MV m−1) and high‐power density (1.16 MW cm−3) at 200 °C, making it an ideal candidate for high‐temperature capacitors. Hopefully, these nanofibers not only serve as excellent nanofillers for high‐temperature energy storage dielectric composites but also holds tremendous potential and inspirational significance for other applications such as electronics, biomedical fields, optics, and catalysis. [ABSTRACT FROM AUTHOR]