Improvement of Carbonyl Groups and Surface Defects in Carbon Nanotubes to Activate Peroxydisulfate for Tetracycline Degradation.

Carbon nanotubes (CNTs) were considered a promising activator for persulfates due to their high electrical conductivity, large specific surface area and low toxicity. The functional groups and surface defects of CNTs could significantly affect their activation performance. In this study, CNTs with high C=O ratio and defect density (CNT-O-H) were prepared through a facile treatment of raw CNTs with HNO oxidation followed by calcination at 800 °C under an argon atmosphere.

Investigation on visible-light photocatalytic performance and mechanism of zinc peroxide for tetracycline degradation and Escherichia coli inactivation.

In this study, zincperoxide (ZnO) with broad energy gap was firstly used for visible-light-induced photocatalytic degradation of tetracycline (TC) and inactivation of Escherichia coli (E. coli). A small amount of ZnO (10 mg) could efficiently degrade 100 mL of 50 mg/L TC in a wide pH range (4-12), and the degradation performance was rarely suppressed by common matrix species and natural water sources.

Efficient degradation of tetracycline in wide pH range using MgNCN/MgO nanocomposites as novel HO activator.

Currently existing Fenton-like catalysts were limited in wastewater treatment owing to their potential transition-metal poisoning, narrow applicable pH range and high dependence on external energy excitation. In this work, the MgNCN/MgO nanocomposites were firstly synthesized by a facile one-pot calcination of melamine and basic magnesium carbonate, and used as novel HO activator for antibiotic removal. It was found that the MgNCN/MgO composite calcined at 550°C with the mass ratio of melamine to basic magnesium carbonate at 2:1, exhibited an excellent catalytic ability to tetracycline (TC) degradation in a wide pH range of 4-10 without any external energy input.

Dramatically enhanced degradation of recalcitrant organic contaminants in MgO/Fe(III) Fenton-like system by organic chelating agents.

Herein, the application of organic acids as chelating agent, including citric acid (CA), tartaric acid (TA), oxalic acid (OA) and ethylenediaminetetraacetic acid (EDTA), to enhance the degradation performance of MgO/Fe(III) system was investigated in the terms of chelating agent dosage, Fe(III) dosage, reaction temperature, initial solution pH and inorganic anion. When the molar ratio of MgO/Fe(III)/chelating agent was 1 : 0.7 : 0.

Facile one-step synthesis of 3D hierarchical flower-like magnesium peroxide for efficient and fast removal of tetracycline from aqueous solution.

Hierarchically three dimensional (3D) flower-like magnesium peroxide (MgO) nanostructures were synthesized through a facile one-step precipitation method. The effects of magnesium salt, reaction temperature, precipitant and surfactant on the morphology and structure of MgO were systematically investigated. The as-obtained samples using magnesium sulfate, ammonia and trisodium citrate were composed of 3D flowers assembled by numerous nanosheets, and SO played a vital role in the formation of flower-like nanostructures.

Enhanced dark adsorption and visible-light-driven photocatalytic properties of narrower-band-gap CuS decorated CuO nanocomposites for efficient removal of organic pollutants.

The CuS-decorated CuO nanocomposites were synthesized by a facile co-precipitation and calcination method, and used as adsorbent and photocatalyst to remove organic pollutants from wastewater. Batch adsorption experiments were conducted to investigate the influences of molar ratio of CuO to CuS, initial solution pH, coexisting anion and temperature on the adsorption performances. As-obtained CuO/CuS-9/1 nanocomposite with high specific surface area (45.

Highly pure MgO nanoparticles as robust solid oxidant for enhanced Fenton-like degradation of organic contaminants.

In typical Fenton/Fenton-like reactions, HO was usually used as an oxidant to degrade organic contaminants. However, liquid HO is unstable, easy to decompose and has high biological toxicity especially at high concentration. Herein, highly pure magnesium peroxide (MgO) nanoparticles were first synthesized and used instead of HO to degrade organic dyes.

Hydrophobic modification of nanoscale zero-valent iron with excellent stability and floatability for efficient removal of floating oil on water.

Usually, nanoscale zero-valent iron (NZVI) cannot float on water because of high density and hydrophilic surface. Herein, alkyltrimethoxysilanes with different carbon chain lengths (C1, C8 and C16) were used as "water-repellent legs" to graft onto NZVI, enduing NZVI with hydrophobic and floatable characteristics like a water strider. The hydrophobic performance of as-modified NZVI materials was found to be better when NZVI was modified by alkyltrimethoxysilane with longer carbon chain, and a large contact angle of 151.

Facile modification of nanoscale zero-valent iron with high stability for Cr(VI) remediation.

In this study, a highly stable nanoscale zero-valent iron composite (HS-NZVI) was obtained via modifying nanoscale zero-valent iron (NZVI) with tetraethyl orthosilicate (TEOS) and hexadecyltrimethoxysilane (HDTMOS), and used for Cr(VI) remediation in aqueous solution. The obtained HS-NZVI remained stable in water without being oxidized for over 12h. After four consecutive runs, the Cr(VI) removal efficiency of HS-NZVI maintained a value of more than 82%.

Anchoring of silver nanoparticles on graphitic carbon nitride sheets for the synergistic catalytic reduction of 4-nitrophenol.

In this paper, a facile process was developed for anchoring of silver nanoparticles on graphitic carbon nitride sheets (Ag/g-CN) with high catalytic activity for reduction of 4-nitrophenol. The morphology and structure of the as-prepared Ag/g-CN composite were investigated by FESEM, TEM, XRD and XPS. The reaction mechanism and the reduction kinetics of 4-nitrophenol under different light irradiation were systematically studied.

Investigation on the efficiency and mechanism of Cd(II) and Pb(II) removal from aqueous solutions using MgO nanoparticles.

In this study, the removal of Cd(II) and Pb(II) from aqueous solutions using MgO nanoparticles prepared by a simple sol-gel method was investigated. The efficiency of Cd(II) and Pb(II) removal was examined through batch adsorption experiments. For the single adsorption of Cd(II) and Pb(II), The adsorption kinetics and isotherm data obeyed well Pseudo-second-order and Langmuir models, indicating the monolayer chemisorption of heavy metal ions.

Influence of water on room-temperature preparation of silver nanoparticles using poly(vinyl pyrrolidone) as reducing agent.

Silver nanoparticles (Ag NPs) were prepared via a wet-chemical method in the presence of poly(vinyl pyrrolidone) (PVP) without other reducing agents at room temperature. The influence of the addition of water on the preparation of Ag NPs was investigated. It was found that water addition has a significant influence on the reduction reaction, resulting in changes of shape, size and optical properties of the particles.

Synthesis and characterization of highly crystalline MgO nanopowders via a modified chemical-precipitation process.

A modified chemical-precipitation method is proposed to synthesize MgO nanopowders with high crystallinity at a low temperature of 400 degrees C using acetic acid as a modifier. The as-obtained intermediates and final products were investigated by Fourier-transformed infrared spectroscopy, thermogravimetric analysis, X-ray diffraction and transmission electron microscopy, respectively. The influence of acetic acid in the MgO preparation process was also investigated by a comparison of the samples without acetic acid, and the mechanism of acetic acid modification is also proposed.

Facile, template-free synthesis of silver nanodendrites with high catalytic activity for the reduction of p-nitrophenol.

Here we report a facile, surfactant-free and template-free synthesis process of highly uniform dendritic silver nanostructures with high catalytic activity for the reduction of p-nitrophenol. By controlling the concentration of AgNO(3) aqueous solution and the reaction time, various shapes of silver nanodendrites (SNDs) could be obtained easily. The effects of different parameters such as concentrations of the reagents and reaction time on the morphology and structure of as-prepared tree-like nanostructures have also been investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM).

A comparative in situ 195Pt electrochemical-NMR investigation of PtRu nanoparticles supported on diverse carbon nanomaterials.

This paper reports a detailed in situ 195Pt electrochemical-nuclear magnetic resonance (EC-NMR) study of PtRu nanoparticles (NPs) that had a nominal atomic ratio of Pt : Ru = 1 : 1 and were supported on carbon nanocoils and carbon black (Vulcan XC-72) respectively. The particle sizes of the two samples were determined by X-ray diffraction using the Sherrer equation: 3.6 nm for the former and 3.