Ti3C2Tx MXene and cellulose-based aerogel phase change composite decorated laminated fabric with excellent electro/solar-thermal conversion and high latent heat.

Wearable heaters have attracted growing attention for maintaining a relatively constant temperature of the human body in cold environments with near zero energy consumption. Herein, we developed a multifunctional laminated fabric with fascinating electro/solar-thermal conversion, thermal energy storage and thermal insulation properties. With cotton fabric as the substrate, MXene/polydimethylsiloxane (PDMS) conductive network was decorated on the upper layer, and carbon nanotube (CNT)/cellulose nanofiber (CNF)/paraffin (PA) aerogel phase change composites were assembled on the bottom layer. Attributed to the strong conductivity and light absorption of MXene and the light/thermal response of CNT and PA components, this wearable laminated fabric broke the limitation of intermittent solar photothermal heating, and integrated multiple heating modes to precisely heat the human body. Meanwhile, the low thermal conductivity of aerogel retarded heat loss. The laminated fabric can help people better adapt to a variety of complex and changeable environments such as cold winter, rainy days and nights. This study provides a promising and energy-efficient avenue for the development of all-day personal thermal management fabrics.

Synthesis of novel magnetic pitch-based hypercrosslinked polymers as adsorbents for effective recovery of Ag+ with high selectivity.

Silver is an important precious metal with superior ductility, electrical and thermal conductivity, photosensitivity, and antibacterial properties. However, without proper recycling and treatment, silver emissions may pose a threat to the human health and subsistence environment due to their toxicity. Therefore, it is environmentally and economically important to recover Ag from waste electronic equipment and anode slime. Herein, carboxyl functionalized modified magnetic nanoparticles (Fe3O4@3-phenylglutaricacid nanoparticles) were designed and prepared to obtain the low-cost magnetic pitch-based HCP adsorbents (MPHCP and P-MPHCP). The novelty of present work is that superior adsorption capacity and magnetic responsiveness of adsorbent can be obtained by a simple one-step Friedel-Crafts reaction with very low-cost raw material. The maximum Ag+ adsorption capacity of MPHCP and P-MPHCP were 321 and 353 mg/g, respectively. The adsorption was completed within a short duration of 15 min for MPHCP and P-MPHCP at an initial Ag+ concentration of 100 mg/L. Moreover, the most selective is P-MPHCP wherein Ag+ is α = 61 times more selective than Pb2+ at a concentration of 100 mg/L.The adsorption capacity of MPHCP and P-MPHCP towards Ag+ still maintains above 89% after ten cycles of adsorption-desorption. This study not only provides new guidance for the development of porous polymeric adsorbents but also provides technical feasibility for the field of recovery and reutilization of precious metals, which has a very extensive practical application prospect.

An in Situ Template for the Synthesis of Tunable Hollow Carbon Particles for High-Performance Lithium-Sulfur Batteries.

Nanostructured materials with hollow interior voids are gaining great attention due to their fantastic geometries and unique physicochemical properties competent for many applications. However, the development of a fast approach to prepare the hollow structured particles remains challenging. Herein, a new and efficient in situ hard-template method was developed to synthesize hollow carbon nano- and microparticles using the as-prepared SiO2 particles as a hard template directly, without any separation, drying, or redispersion. In this way, the hollow carbon particles with tunable diameters and shell thickness can be synthesized readily, which is simpler and more efficient than the traditional ones. In addition, the universality of this strategy allows us to study the different behaviors of hollow carbon particles in lithium-sulfur batteries when the architectures of hollow particles (i.e., diameter, shell thickness, etc.) were changed. We believe that this in situ method is applicable for synthesizing other core-shell or hollow structured materials (e.g., metal oxide), and also, the high performance of hollow carbon particles in lithium-sulfur batteries and beyond can be further explored.

Luminescence and energy transfer of Tb3+-doped BaO-Gd2O3-Al2O3-B2O3-SiO2 glasses.

Transparent Tb3+-doped BaO-Gd2O3-Al2O3-B2O3-SiO2 glasses with the greater than 4g/cm3 were prepared by high temperature melting method and its luminescent properties have been investigated by measured UV-vis transmission, excitation, emission and luminescence decay spectra. The transmission spectrum shows there are three weak absorption bands locate at about 312, 378 and 484nm in the glasses and it has good transmittance in the visible spectrum region. Intense green emission can be observed under UV excitation. The effective energy transfer from Gd3+ ion to Tb3+ ion could occur and sensitize the luminescence of Tb3+ ion. The green emission intensity of Tb3+ ion could change with the increasing SiO2/B2O3 ratio in the borosilicate glass matrix. With the increasing concentration of Tb3+ ion, 5D4→7FJ transitions could be enhanced through the cross relaxation between the two nearby Tb3+ ions. Luminescence decay time of 2.12ms from 546nm emission is obtained. The results indicate that Tb3+-doped BaO-Gd2O3-Al2O3-B2O3-SiO2 glasses would be potential scintillating material for applications in X-ray imaging.

Luminescence properties of Tb(3+)-doped borosilicate scintillating glass under UV excitation.

Transparent Li2O-BaO-La2O3-Al2O3-B2O3-SiO2 glasses doped with Tb(3+) ion were prepared by high temperature melting method. Luminescence properties of Tb(3+)-doped borosilicate glasses have been investigated by transmission, excitation, emission and luminescence decay measurements. The transmission spectrum shows the glass has good transmittance in the visible region. Under the 236 nm UV excitation the intense green emission from (5)D4 level is observed in Tb(3+)-doped borosilicate glass, comparable in intensity to the violet-blue emission starting from the (5)D3 level. The green emission intensity of Tb(3+) ion firstly increases and then decreases with the decreasing B2O3/SiO2 ratio in glass matrix. (5)D4→(7)FJ (J=6, 5, 4 and 3) transitions of Tb(3+) ion in borosilicate glass are greatly enhanced with increasing concentration of Tb(3+) through the cross relaxation [Tb(3+) ((5)D3)+Tb(3+) ((7)F6)→Tb(3+) ((5)D4)+Tb(3+) ((7)F0)] between two Tb(3+) ions. Luminescence decay time of 2.13 ms is obtained for the emission transitions starting from (5)D4 level in 2.5Li2O-20BaO-20La2O3-2.5Al2O3-20B2O3-35SiO2-0.5Tb4O7 glass. The results show that Tb(3+)-doped borosilicate glasses would be potential candidates for scintillating material for static X-ray imaging.

Chemical oxidation of sulfadiazine by the Fenton process: kinetics, pathways, toxicity evaluation.

This paper investigated sulfadiazine oxidation by the Fenton process under various reaction conditions. The reaction conditions tested in the experiments included the initial pH value of reaction solutions, and the dosages of ferrous ions and hydrogen peroxide. Under the reaction conditions with pH 3, 0.25 mM of ferrous ion and 2 mM of hydrogen peroxide, a removal efficiency of nearly 100% was achieved for sulfadiazine. A series of intermediate products including 4-OH-sulfadiazine/or 5-OH-sulfadiazine, 2-aminopyrimidine, sulfanilamide, formic acid, and oxalic acid were identified. Based on these products, the possible oxidation pathway of sulfadiazine by Fenton's reagent was proposed. The toxicity evaluation of reaction solutions showed increased antimicrobial effects following the Fenton oxidation process. The results from this study suggest that the Fenton oxidation process could remove sulfadiazine, but also increase solution toxicity due to the presence of more toxic products.

Templated preparation of porous magnetic microspheres and their application in removal of cationic dyes from wastewater.

Porous magnetic microspheres with large particle size (350-450 microm) were prepared with sulfonated macroporous polydivinylbenzene as a template. The preparation process included ferrous ion exchange and following oxidation by hydrogen peroxide. The results showed that the weight fraction of magnetic nanoparticles exceeded 20 wt% in microspheres after the preparation process was repeated three times. X-ray diffraction profiles indicated that the crystalline phase of as-formed magnetic nanoparticles was magnetite (Fe(3)O(4)). TEM images revealed rod-like magnetite crystal after the first oxidation cycle, however, the crystal morphologies were transferred into random shape after more oxidation cycles. The applicability of porous magnetic microspheres for removal of cationic dyes from water was also explored. The results exhibited that basic fuchsin and methyl violet could be quickly removed from water with high efficiency. More importantly, the magnetic microspheres could be easily regenerated and repeatedly employed for wastewater treatment. Therefore, a novel methodology was provided for fast removal cationic dyes from wastewater.

Hyperbranched ferrocenyl polymer film with high charge transport efficiency.

The electrochemical behaviors of hyperbranched poly(ferrocenyl-methylsilane) (HPFMS) and linear oligo(ferrocenyldimethylsilane) (LOFS) films were studied systematically by cyclic voltammetry and chronocoulometry under different polymer coverage and solvents. Both poly(ferrocenylsilanes) show stable cyclic voltammographs in LiClO 4 solutions. Compared with LOFS films, HPFMS films exhibit higher charge transport efficiency because of their hyperbranched structure: peak current ( i p) and apparent diffusion coefficient ( D app) for HPFMS films are larger than those for LOFS films, especially at high polymer coverage (3.8 x 10 (-11) vs 3.9 x 10 (-12) cm2/s for HPFMS and LOFS film at the coverage of 2.1 x 10 (-6) mol Fc/cm2). The conceptual models of electrode processes for HPFMS and LOFS films were proposed to account for higher charge transport efficiency of HPFMS films. It is also found that a solvent with the appropriate solubility parameter and polarity, lower viscosity, and higher dielectric constant is in favor of charge transport through polymer films, which is consistent with the proposed model of electrode process for HPFMS films. These results imply that hyperbranched ferrocenyl polymers have the potential to be excellent chemical sensor materials with convenient synthesis and high sensitivity.

Study on anion electrochemical recognition based on a novel ferrocenyl compound with multiple binding sites.

A novel ferrocenyl anion receptor N, N, N, N-(dimethyl, ethyl, ferrocenecarboxylic amidodimethylene) ammonium fluoborate 2 with multiple binding sites was synthesized. Its anion recognition behaviors were investigated by CV, 1H NMR and UV-vis spectrum. It was found that the combination of two interactions enforced the anion binding ability and the binding selectivity of 2 to phosphate anion. The effects of scan rate on the CV curves of 2 with phosphate were also investigated. In different scan rate, the CV curves kept stable which indicated the strong binding between 2 and phosphate. According to relationships of peak potential, peak currents and scan rate of 2 binding with phosphate, the kinetic parameters of electrode process such as diffusion coefficient Dapp, surface transfer coefficient alphan alpha, and standard rate constant k0 were calculated.