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Film capacitors have shown great potential in high-power energy storage devices due to their high breakdown strength and low dielectric loss. However, the state-of-the-art commercial capacitor dielectric, biaxially oriented polypropylene (BOPP), exhibits limited energy storage density below 2 J cm−3 because of its low dielectric constant (approximately 2.2 at 103 Hz). In this work, we present a novel PP-based nanocomposites by incorporating nonpolar sub-10 nm sized TiO 2 nanoparticles into the PP matrix for the first time. The nonpolar TiO 2 nanoparticles are functionalized with Trioctylphosphine oxide (TOPO) ligands, ensuring excellent compatibility and dispersion of the TiO 2 fillers in the PP matrix, resulting in a homogeneous dielectric PP nanocomposite. Moreover, the TOPO ligand, with lower LUMO energy level and higher HOMO level than that of PP matrix, serves as an energy trap to capture carriers upon their occurrence. Furthermore, the well-dispersed sub-10 nm sized TiO 2 nanoparticles enlarges the interfacial area, thereby increasing the interfacial polarization and the dielectric constant. The resultant PP nanocomposites exhibit a high discharged energy density of 4.19 J cm−3 at 600 MV m−1, representing a remarkable 74.9% increase compared to that of the pure PP films. This work provides a brand-new strategy for constructing homogeneous PP nanocomposite dielectrics by incorporating nonpolar sub-10 nm sized TiO 2 nanoparticles as fillers. And this approach is critical for the design of high energy density PP-based nanocomposites. [Display omitted] • Nonpolar sub-10 nm TiO 2 nanoparticles were incorporated into polypropylene (PP) to form a homogeneous PP nanocomposite. • The nonpolar TiO 2 , with TOPO ligand on the surface, exhibited excellent compatibility and dispersion within PP matrix. • The TOPO ligands on the TiO 2 filler surface acted as effective energy traps for free carriers upon they occur. • The sub-10 nm TiO 2 fillers enlarge the interfacial area, attributing to enhanced interfacial polarization. • The resultant PP nanocomposites exhibit an increased discharged energy density of 4.19 J cm-3 at 600 MV m-1. [ABSTRACT FROM AUTHOR]

A membrane adsorbent has been rationally designed to simplify the solid-liquid separation process and avoid adsorbent loss and leakage. The iron-based MOF was grown in situ on the surface of nylon membrane substrates by layer-by-layer method, and the as-synthesized MIL@nylon was post-treated with sodium borohydride to generate iron oxide nanoparticles within the MOF, named HFO@MIL@nylon. SEM, XRD, FT-IR and XPS characterization confirmed successful loading of MOF and the generation of nanoparticles in the MOF. The adsorption properties of HFO@MIL@nylon were tested. The results show that the adsorption process of phosphate accords with Langmuir and quasi-second-order kinetic model, with an adsorption capacity of 63.3 mg/g based on the mass of HFO@MIL. HFO@MIL@nylon could maintain high performance in a wide pH range. And the common interference ions SO 4 2-, NO 3 -, Cl- only extended minus effect on the removal which means HFO@MIL@nylon has a good selectivity towards phosphorus. In addition, HFO@MIL@nylon membrane could work as a filter membrane, purifying 550 mL water of 200 μg-P/L with a water permeance of 1054 L/m2 h MPa. • A MOF-based composite having been loaded onto a commercial micro-filtration membrane. • An adsorbent in membrane form to simplify the process of separation and avoid adsorbents loss. • The adsorption capacity is 63.3 mg/g based on the mass of HFO@MIL. • HFO@MIL@nylon could maintain high performance over a wide pH range. • HFO@MIL@nylon could work as a filter membrane, purifying 550 mL water of 200 μg-P/L with a high permeance of 1054 L/m2 h MPa. [ABSTRACT FROM AUTHOR]

Molecular hydrogen, a valuable clean energy fuel and industrial feedstock, is commonly produced by steam reforming of fossil fuels, a process that results in the co-generation of CO 2 . Strategies that produce H 2 without CO 2 emissions focus on water-splitting powered by solar or wind energy. Here, we introduce a new approach in which energy derived from the oxidation of waste organic matter is used to subsidize the electrical energy consumed by electrochemical H 2 generation. The primary gas product is H 2 , with minimal O 2 contamination, avoiding the purification step required for conventional water electrolysis. The energy efficiency (i.e., energy from H 2 combustion ÷ input electrical energy × 100%) ranges from 214% to 304%. We also demonstrate a sustained cycling operation with concomitant treatment of domestic and industrial wastewater. These findings open the door to recovery of H 2 from other dilute reservoirs of organic matter, such as marine sediment. [ABSTRACT FROM AUTHOR]

Despite the great success of fluorescence sensing array application in bioanalysis, the photo-quenching problem accompanied with high surface fluorophore density has become the bottleneck for its further sensitivity improvement. Herein, a fluorescence polyethylene glycol (PEG) hydrogel array was developed for highly sensitive microRNA detection based on interfacial cation exchange amplification coupled with DNA hybridization chain reaction (HCR). The carboxylate PEG hydrogel array was fabricated on glass slide via photo polymerization and modified with miRNA capture probe, target miRNA binding triggered HCR in hydrogel with biotin labelled DNA probes to generate numerous DNA polymer chains where biotinylated CdS QDs were subsequently conjugated with a streptavidin bridge. Interfacial cation exchange amplification was triggered in hydrogel upon the introduction of Ag+ and Rhod-5N, and abundant Cd2+ was released from CdS to bind with Rhod-5N for substantial fluorescence enhancement. The aqueous-like environment of hydrogel eliminated the fluorescence quenching and simplified experiment process by performing cation exchange reaction at interface with direct result. The linear range for model target miRNA-21 was 1 fM to 500 pM with a detection limit of 0.835 fM. Taking advantage of the nonfouling property of PEG hydrogel, direct quantification of miRNA-21 was achieved from crude cancer cell lysates with a detection limit down to 10 equivalent cells. The expressions of circulating miRNA-21 in clinical serum samples were also assessed with comparable results from RT-PCR. The developed hydrogel array provides a universal platform for highly sensitive fluorescence sensing, and would benefit clinical non-invasive disease diagnosis. Image 1 • A fluorescence polyethylene glycol hydrogel array is designed for miRNA detection with limit of detection down to 0.835 fM. • Hybridization chain reaction (HCR) is performed in hydrogel framework upon target miRNA initiation. • Fluorescence signal amplification is achieved via interfacial cation exchange in aqueous like environment of hydrogel. • Direct detections of miRNA-21 were achieved from lysate of 10 equivalent cells and clinical serum samples. [ABSTRACT FROM AUTHOR]

Abstract: A novel coordination polymer [Zn(4,4′-bipyridine)(Hptc)·H2O] n (H3ptc=pyridine-2,4,6-tricarboxylic acid) (1) was obtained via hydrothermal method and characterized by elemental analyses, IR spectrum, TG analysis, luminescent spectrum and single-crystal X-ray diffraction analysis. Single-crystal structural analysis reveals that the center Zn2+ions are linked by bridging – carboxylate group of H3ptc, to form helix. The winding axes parallel to the b axis and the pitch to the length is 7.147Å. Two kinds (one is left handed and the other is right handed) of parallel helices existed correspondingly, which are connected by rigid 4,4′-bipyridine ligand to give a 2D puckered herringbone structural motif. [Copyright &y& Elsevier]

• An Au layer was deposited to protect the Ag nanoplates to enhance their stability. • p-Ag@Au NPLs could enhance the silver ion release on-demand upon laser irradiation. • Good photothermal therapy effect and the anti-bacterial potential were assessed. • Possibility of an effective antibacterial agent with low cytotoxicity. Although silver nanoparticles are considered as promising antibacterial agents because of their antibacterial activity, the acute cytotoxicity of Ag+ released from Ag nanoparticles restricts their potential practical applications. Herein, porous Ag@Au nanoplates, which could balance the Ag+ release and the toxicity of Ag naoparticles, were fabricated by stepwise seed-mediated growth and oxidation. Laser irradiation further boosted their antimicrobial activity, and significantly accelerated the curing rate of wound. Comparing with Ag nanoplates, the irradiated porous Ag@Au nanoplates showed the similar antibiotic ability against S. aureus strains and lower cytotoxicity in vitro. When the porous Ag@Au nanoplates were applied to treat S. aureus -infected wound, they had the best curing effect. Thus, these porous Ag@Au nanoplates could act as promising antibacterial agents for wound healing applications. [ABSTRACT FROM AUTHOR]