Integration of high visible-light-driven ternary dual Z-scheme AgVO3-InVO4/g-C3N4 heterojunction nanocomposite for enhanced uranium(VI) photoreduction separation.

With deepening application of nuclear power technology, the problem of water ecological environment pollution caused by uranium (U(VI)) is becoming increasingly serious. Photoreduction separation of U(VI) on photocatalysts is considered as an effective strategy to solve uranium pollution. In this work, a novel ternary dual Z-scheme AgVO3-InVO4/g-C3N4 heterojunction (Z-AIGH) nanocomposite with high surface area (73.45 m2 g-1, Z-AIGH2) was designed. The batch adsorption experiment in dark environment showed that Z-AIGH2 nanocomposite had an excellent U(VI) adsorption performance. As for photocatalytic experiments, Z-AIGH2 exhibited a rapid photocatalytic response for separating U(VI) without any organic sacrifice agents. The U(VI) separation rate on Z-AIGH2 nanocomposite was over 98.7% after only 20.0 min visible light irradiation (T = 298 K, CU(Ⅵ) = 10.0 mg L-1, m/V = 0.1 g L-1 and pH = 7.0). Z-AIGH2 nanocomposite also showed good selectivity and cycle stability. The U(VI) removal rate of Z-AIGH2 nanocomposite after fifth cycles was about 96.1% (T = 298 K, CU(Ⅵ) = 10.0 mg L-1, m/V = 0.1 g L-1 and pH = 7.0). High photocatalytic activity of Z-AIGH2 for U(VI) was attributed to the construction of ternary dual Z-scheme heterojunction structure and ant nest-like hole structure. Based on above results, Z-AIGH2 nanocomposite had great potential for water environment renovation.

Design of Laser Photothermal Conversion Membranes Based on Fluorinated Graphene.

Laser photothermal-conversion membranes have great potential applications in many different fields, including laser ignition. However, the demand for real-time, high heat output calls for an extra heat-releasing pattern other than the traditional luminous energy-thermal, energy-conversion mechanism. Herein, it was found that fluorinated graphene (FG) was a promising candidate for laser photothermal conversion due to the extra chemical energy-thermal, energy-conversion process, which originated from a self-redox reaction under laser irradiation. Moreover, an easy sonochemical, exfoliation-filtration protocol was provided for the preparation of the fluorinated, graphene-based, free-standing membranes. In brief, FG flakes were arranged into flower-like patterns and formed freestanding, carpet-like membranes with layered structures with the filtration of FG suspension, which was obtained from exfoliating fluorographite in N-methylpyrrolidone. Furthermore, this contribution also revealed that modifying the FG membranes with polytetrafluoroethylene (PTFE) was helpful for improving the photothermal-conversion properties. With the construction of the FG/PTFE composited structure, higher heat output could be achieved when a laser pulse is applied to the composite membranes. This work revealed the great potential of fluorinated graphene in laser photothermal conversion, and provided an alternative route of introducing a chemical energy-thermal, energy-conversion process for achieving high heat output under laser irradiation.

Low-Temperature Deposition of Transparent Conducting Films Applied to Flexible Electrochromic Devices.

Here, we compare two different transparent conducting oxides (TCOs), namely indium tin oxide (ITO) and indium zinc tin oxide (IZTO), fabricated as transparent conducting films using processes that require different temperatures. ITO and IZTO films were prepared at 230 °C and at room temperature, respectively, on glass and polyethylene terephthalate (PET) substrates using reactive magnetron sputtering. Electrochromic WO3 films deposited on ITO-based and IZTO-based ECDs using vacuum cathodic arc plasma (CAP) were investigated. IZTO-based ECDs have higher optical transmittance modulation, ΔT = 63% [from Tbleaching (90.01%) to Tcoloration (28.51%)], than ITO-based ECDs, ΔT = 59%. ECDs consisted of a working electrochromic electrode (WO3/IZTO/PET) and a counter-electrode (Pt mesh) in a 0.2 M LiClO4/perchlorate (LiClO4/PC) liquid electrolyte solution with an active area of 3 cm × 4 cm a calculated bleaching time tc of 21.01 s and a coloration time tb of 4.7 s with varying potential from -1.3 V (coloration potential, Vc) to 0.3 V (bleaching potential, Vb).

A facile synthesis of graphene oxide/locust bean gum hybrid aerogel for water purification.

Graphene oxide/locust bean gum (GO/LBG) aerogels, synthesized in an ice crystal template without using any chemical modifiers, were used for the treatment of water pollution. Various characterization results showed that GO/LBG aerogel exhibited a network-like three-dimensional (3D) structure with large specific surface area. The adsorption data revealed that GO/LBG aerogels with GO/LBG mass ratio of 1:4 (GO/LBG-1 aerogels) exhibited more prominent adsorption properties for Rhodamine-B (RhB, 514.5 mgg-1) than Indigo Carmine (IC, 134.6 mgg-1). Simultaneously, GO/LBG-1 aerogels could selectively remove RhB from a binary mixed solution of RhB-IC dyes. Furthermore, GO/LBG-1 aerogels also displayed excellent reusability and could still reach 92.4 % after ten cycles. Based on the above results, GO/LBG-1 aerogel could be considered as an ideal adsorbent with potential application value for removing water-soluble RhB from wastewater.

Fast response of complementary electrochromic device based on WO3/NiO electrodes.

Nanoporous structures have proven as an effective way for enhanced electrochromic performance by providing a large surface area can get fast ion/electron transfer path, leading to larger optical modulation and fast response time. Herein, for the first time, application of vacuum cathodic arc plasma (CAP) deposition technology to the synthesis of WO3/NiO electrode films on ITO glass for use in fabricating complementary electrochromic devices (ECDs) with a ITO/WO3/LiClO4-Perchlorate solution/NiO/ITO structure. Our objective was to optimize electrochromic performance through the creation of electrodes with a nanoporous structure. We also examined the influence of WO3 film thickness on the electrochemical and optical characteristics in terms of surface charge capacity and diffusion coefficients. The resulting 200-nm-thick WO3 films achieved ion diffusion coefficients of (7.35 × 10-10 (oxidation) and 4.92 × 10-10 cm2/s (reduction)). The complementary charge capacity ratio of WO3 (200 nm thickness)/NiO (60 nm thickness) has impressive reversibility of 98%. A demonstration ECD device (3 × 4 cm2) achieved optical modulation (ΔT) of 46% and switching times of 3.1 sec (coloration) and 4.6 sec (bleaching) at a wavelength of 633 nm. In terms of durability, the proposed ECD achieved ΔT of 43% after 2500 cycles; i.e., 93% of the initial device.

Research on Hybrid Feature Selection Method Based on Iterative Approximation Markov Blanket.

The basic experimental data of traditional Chinese medicine are generally obtained by high-performance liquid chromatography and mass spectrometry. The data often show the characteristics of high dimensionality and few samples, and there are many irrelevant features and redundant features in the data, which bring challenges to the in-depth exploration of Chinese medicine material information. A hybrid feature selection method based on iterative approximate Markov blanket (CI_AMB) is proposed in the paper. The method uses the maximum information coefficient to measure the correlation between features and target variables and achieves the purpose of filtering irrelevant features according to the evaluation criteria, firstly. The iterative approximation Markov blanket strategy analyzes the redundancy between features and implements the elimination of redundant features and then selects an effective feature subset finally. Comparative experiments using traditional Chinese medicine material basic experimental data and UCI's multiple public datasets show that the new method has a better advantage to select a small number of highly explanatory features, compared with Lasso, XGBoost, and the classic approximate Markov blanket method.

Indium-Zinc-Tin-Oxide Film Prepared by Reactive Magnetron Sputtering for Electrochromic Applications.

This paper reports on the fabrication of indium-zinc-tin-oxide (IZTO) transparent conductive film deposited by direct current (DC) reactive magnetron sputtering. The electrical, structural, and optical properties of IZTO film were investigated by Hall measurement, X-ray diffraction (XRD), and optical transmission spectroscopy with various sputtering powers. The IZTO film prepared used power at 100 W showed the lowest resistivity of 5.2 × 10-4 Ω cm. To accomplish rapid switching and high optical modulation, we have fabricated an electrochromic device (ECD) consisting of an working electrode (WO3 electrode film deposited on IZTO/ITO/glass) and a counter-electrode (Pt mesh) in 0.2 M LiClO4/PC liquid solution. The device demonstrated an optical contrast of 44% and switching times of 4.6 s and 8.1 s for the coloring and bleaching state, respectively, at the wavelength of 550 nm.