Zhejiang University

About: Zhejiang University is a education organization based out in Hangzhou, Zhejiang, China. It is known for research contribution in the topics: Catalysis & Population. The organization has 161257 authors who have published 183264 publications receiving 3417592 citations. The organization is also known as: Chekiang University & Zheda.

High-Flux Graphene Oxide Nanofiltration Membrane Intercalated by Carbon Nanotubes

Abstract: A sort of novel high-flux nanofiltration membrane was fabricated by synergistic assembling of graphene and multiwalled carbon nanotubes (MWNTs), in which graphene played the role of molecular sieving and MWNTs expanded the interlayer space between neighbored graphene sheets. The MWNT-intercalated graphene nanofiltration membrane (G-CNTm) showed a water flux up to 11.3 L m(-2) h(-1) bar(-1), more than 2 times that of the neat graphene nanofiltration membrane (GNm), while keeping high dye rejection (>99% for Direct Yellow and >96% Methyl Orange). The G-CNTm also showed good rejection ratio for salt ions (i.e., 83.5% for Na2SO4, 51.4% for NaCl). We also explored the antifouling performance of G-CNTm and GNm with bovine serum albumin (BSA), sodium alginate (SA) and humic acid (HA). Both G-CNTm and GNm possessed excellent antifouling performance for SA and HA but inferior for BSA because of the strong interaction between protein and graphene sheets.

Role of primary active species and TiO2 surface characteristic in UV-illuminated photodegradation of Acid Orange 7

Abstract: Controversy still exists over whether photocatalytic oxidation proceeds via OH radicals, valence band holes, O2− or H2O2. In this paper, the role of these primary oxidants in the photodegradation of an azo dye, Acid Orange 7 (AO7) in UV-illuminated TiO2 suspension was investigated. Little influence of methanol or isopropanol on the degradation indicated that the oxidation was not primarily proceeding by reaction between OH radicals and AO7, because alcohols could effectively scavenge OH radicals. But the presence of I− (hole scavenger) significantly inhibited the degradation, thus suggesting that holes played a major role. Then, experiments carried out in acetonitrile, methanol or isopropanol solvent confirmed the major role of holes, since OH radicals were minimized in dry solvent. In addition, it was suggested that O2− and H2O2 had a negligible effect when Cr(VI) was used as electron scavenger instead of O2. The effects of surface modification by F− or SO42− on the initial steps of photodegradation were also investigated. The hydroxyl groups on the surface of TiO2 were replaced by F− or SO42− and there were little adsorbed AO7 molecules to be trapped by hole, so the initial process could shift progressively from hole-dominated surface reaction to homogeneous radical reaction in bulk solution. Discussion about the relationship between adsorption and photodegradation indicated that the degradation rate was not strongly affected by the actual location amount of organics on TiO2 surface.

Foldable interpenetrated metal-organic frameworks/carbon nanotubes thin film for lithium-sulfur batteries.

Abstract: Lithium-sulfur batteries are promising technologies for powering flexible devices due to their high energy density, low cost and environmental friendliness, when the insulating nature, shuttle effect and volume expansion of sulfur electrodes are well addressed. Here, we report a strategy of using foldable interpenetrated metal-organic frameworks/carbon nanotubes thin film for binder-free advanced lithium-sulfur batteries through a facile confinement conversion. The carbon nanotubes interpenetrate through the metal-organic frameworks crystal and interweave the electrode into a stratified structure to provide both conductivity and structural integrity, while the highly porous metal-organic frameworks endow the electrode with strong sulfur confinement to achieve good cyclability. These hierarchical porous interpenetrated three-dimensional conductive networks with well confined S8 lead to high sulfur loading and utilization, as well as high volumetric energy density.