Yongkui Huang

Photocatalytic Degradation of Rhodamine B with H3PW12O40/SiO2 Sensitized by H2O2

In order to remove aquatic organic dye contaminants by utilizing the inexpensive and inexhaustible solar energy, the Keggin-type H3PW12O40 was loaded on the surface of SiO2 with the sol-gel method and sensitized by H2O2 solution. The photocatalytic degradation of rhodamine B (RhB) by H3PW12O40/SiO2(x) under simulated natural light irradiation was investigated. The effects of the initial RhB concentration, the solution pH, and catalyst dosage on the photocatalytic degradation rate of RhB were also studied. The results demonstrated that at optimal condition (initial concentration of methyl orange is 10 mg/L, catalyst dosage is 0.8 g, and the pH is 2.5) the degradation rate of RhB is as high as 97.7% after 2 h under simulated natural light irradiation. The reaction of photocatalysis for RhB can be expressed as a first-order kinetic model.

Efficient Photocatalytic Bilirubin Removal over the Biocompatible Core/Shell P25/g-C 3 N 4 Heterojunctions with Metal-free Exposed Surfaces under Moderate Green Light Irradiation

Highly-monodispersed g-C3N4/TiO2 hybrids with a core/shell structure were synthesized from a simple room temperature impregnation method, in which g-C3N4 was coated through self-assembly on the commercially available Degussa P25 TiO2 nanoparticles. Structural and surface characterizations showed that the presence of g-C3N4 notably affected the light absorption characteristics of TiO2. The g-C3N4/TiO2 heterojunctions with metal-free exposed surfaces were directly used as biocompatible photocatalysts for simulated jaundice phototherapy under low-power green-light irradiation. The photocatalytic activity and stability of g-C3N4/TiO2 were enhanced relative to pure P25 or g-C3N4, which could be ascribed to the effective Z-scheme separation of photo-induced charge carriers in g-C3N4/TiO2 heterojunction. The photoactivity was maximized in the 4 wt.% g-C3N4-coated P25, as the bilirubin removal rate under green light irradiation was more than 5-fold higher than that under the clinically-used blue light without any photocatalyst. This study approves the future applications of the photocatalyst-assisted bilirubin removal in jaundice treatment under moderate green light which is more tolerable by humans.

Photocatalytic Degradation of Methyl Violet with TiSiW12O40/TiO2

The photocatalytic degradation of methyl violet using TiSiW12O40/TiO2 as a novel eco-friendly catalyst under simulated natural light irradiation was investigated. The physical characterizations were carried out by TG/DTA, FT-IR, XRD, and UV-visible spectra. The effects of the initial methyl violet concentration, the solution pH, and catalyst dosage on the photocatalytic degradation rate of methyl violet were also examined. The results demonstrated that at optimal condition (initial concentration of methyl violet is 20 mg/L, catalyst dosage is 0.3 g, and the pH is 5.5), the degradation rate of methyl violet is as high as 82.4% after 3 h under simulated natural light irradiation. The reaction of photocatalysis for methyl violet can be expressed as first-order kinetic model.

Synthesis and properties of magnetic carbon nanocages particles for dye removal

Magnetic carbon nanocages (MCNCs) with multiform pore structure have been synthesized by a simple low temperature carbonization process. Biorenewable lignin was used as a cheap and carbon-rich precursor for the first time. The products were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, energy dispersive X-ray spectroscopy (EDS), vibrating samplemagnetometer (VSM), transmission electronmicroscopy (TEM), and Raman spectrum. XRDpattern and Raman spectrum showed that the product has a high degree of graphitization crystallinity. TEM micrograph indicated that the synthesized MCNCs have the hierarchical pore and cage structure. Due to these characteristics, the obtained magnetic carbon nanocages can be used as efficient and recycled adsorbents in the removal of dye staff from textile wastewater.

Uniformity dispersive, anti-coking core@double-shell-structured Co@SiO2@C: Effect of graphitic carbon modified interior pore-walls on C5+ selectivity in Fischer-Tropsch synthesis.

Highly dispersed Co nanoparticles with proper interaction with mesoporous support are benefit for the suppression of self-aggregation, which enhances its Fischer-Tropsch synthesis (FTs) activity. However, construct such Co based supported catalysts with high activity and stability in FTs by conventional mesoporous support, especially the common used mesoporous SiO2, has proven challenging due to their undesirable hydrothermal stability and poor reducibility. Herein, we developed a unique core@double-shell Co@SiO2@C structure with optimized interface of the mesoporous catalyst by introducing graphitic carbon layer which can weaken the interaction between metallic Co and silica. Transmission electron microscopy (TEM) images, together with Nitrogen adsorption-desorption characterization result, proved the well-defined core@double-shell structure of graphitic carbon modified catalyst. The Co@SiO2@C-2 material produced after optimizing the calcination temperature to 600°C process large surface area and pore volume, and show higher CO conversion (62.2%) and C5+ selectivity (62.2%) than Co3O4@SiO2 in a period of 100h. The significant improvement in the FTS performance of Co@SiO2@C is not only attributed to a good synergistic effect by a combination of the Co dispersion and reducibility. The unique core@double-shell structure with graphitic carbon modified interior pore-walls also contributes to the formation of heavy hydrocarbon, as well as the protecting with the metallic Co particles away from oxidation and aggregation.

Photocatalytic Degradation of Organic Dyes by H4SiW6Mo6O40/SiO2 Sensitized by H2O2

H4SiW6Mo6O40/SiO2 was sensitized by H2O2 solution that significantly improved its catalytic activity under simulated natural light. Degradation of basic fuchsin was used as a probe reaction to explore the influencing factors on the photodegradation reaction. The results showed that the optimal conditions were as follows: initial concentration of basic fuchsin 8 mg/L, pH 2.5, catalyst dosage 4 g/L, and light irradiation time 4 h. Under these conditions, the degradation rate of basic fuchsin is 98%. The reaction of photocatalysis for basic fuchsin can be expressed as the first-order kinetic model. After being used continuously for four times, the catalyst kept the inherent photocatalytic activity for degradation of dyes. The photodegradation of malachite green, methyl orange, methylene blue, and rhodamine B were also tested, and the degradation rate of dyes can reach 90%–98%.