Rare-earth functioned Bi2WO6 nanofibers via electrospinning: Boosted catalytic performance and contact-free temperature monitoring on degradation process

The pod-shaped TiO 2 nano burst tubes (TiO 2 NBTs) were prepared by the combination of electrospinning and impregnation calcination with oxalic acid (H 2 C 2 O 4 ), polystyrene (PS) and tetrabutyl titanate. The silver nanoparticles (AgNPs) were loaded onto the surface of TiO 2 NBTs by ultraviolet light reduction method to prepare pod-shaped Ag@TiO 2 NBTs. In this work, we analysed the effect of the amount of oxalic acid on the cracking degree of TiO 2 NBTs; the effect of the concentration of AgNO 3 solution on the particle size and loading of AgNPs on the surface of TiO 2 NBTs. Scanning electron microscopy and transmission electron microscopy investigated the surface morphology of samples. X-ray diffraction and X-ray photoelectron spectroscopy characterized the structure and composition of samples. Rhodamine B (RhB) solution was used to evaluate the photocatalytic activity of pod-shaped TiO 2 NBTs and Ag@TiO 2 NBTs. The results showed that TiO 2 NBTs degraded 91.0% of RhB under ultraviolet light, Ag@TiO 2 NBTs degraded 95.5% under visible light for 75 and 60 min, respectively. The degradation process of both samples was consistent with the Langmuir–Hinshelwood first-order kinetic equation. Therefore, the catalytic performance of the sample is: Ag@TiO 2 NBTs > TiO 2 NBTs > TiO 2 nanotubes.

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Degradation Behavior, Transport Mechanism and Osteogenic Activity of Mg–Zn–RE Alloy Membranes in Critical-Sized Rat Calvarial Defects

Coatings ◽

10.3390/coatings10050496 ◽

2020 ◽

Vol 10 (5) ◽

pp. 496

Author(s):

Mingyu Zhao ◽

Guanqi Liu ◽

Ying Li ◽

Xiaodong Yu ◽

Shenpo Yuan ◽

...

Keyword(s):

Electron Microscopy ◽

Rare Earth ◽

Rare Earth Elements ◽

Transport Mechanism ◽

Degradation Process ◽

Lymph System ◽

Transmission Electron ◽

Calvarial Defects ◽

Rat Calvarial Defect

In this study, a specific Mg–Zn–RE alloy membrane with 6 wt.% zinc and 2.7 wt.% rare earth elements (Y, Gd, La and Ce) was prepared to investigate implant degradation, transport mechanism and guide bone regeneration in vivo. The Mg-membrane microstructure and precipitates were characterized by the scanning electron microscopy (SEM) and the transmission electron microscopy (TEM). The Mg-membrane degradation process and effect on osteogenesis were investigated in a critical-sized rat calvarial defect model via micro-CT examination and hard tissue slicing after 2-, 5- and 8-week implants. Then, the distribution of elements in organs after 1-, 2- and 4-weeks implantation was examined to explore their transportation routes. Results showed that two types of precipitates had formed in the Mg–membrane after a 10-h heat treatment at 175 °C: γ-phase MgZn precipitation with dissolved La, Ce and Gd, and W-phase Mg3(Y, Gd)2Zn3 precipitation rich in Y and Gd. In the degradation process of the Mg-membrane, the Mg matrix degraded first, and the rare earth-rich precipitation particles were transferred to a more stable phosphate compound. The element release rate was dependent on the precipitate type and composition. Rare earth elements may be transported mainly through the lymph system. The defects were repaired rapidly by the membranes. The Mg-membrane used in the present study showed excellent biocompatibility and enhanced bone formation in the vicinity of the implants.

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Rare-earth metal oxide hybridized PtFe nanocrystals synthesized via microfluidic process for enhanced electrochemical catalytic performance

Electrochimica Acta ◽

10.1016/j.electacta.2018.12.132 ◽

2019 ◽

Vol 299 ◽

pp. 80-88 ◽

Cited By ~ 11

Author(s):

Jugang Ma ◽

Xin Tong ◽

Junmei Wang ◽

Gaixia Zhang ◽

Yuepeng Lv ◽

...

Keyword(s):

Rare Earth ◽

Metal Oxide ◽

Rare Earth Metal ◽

Earth Metal ◽

Catalytic Performance ◽

Rare Earth Metal Oxide

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Dehydration of Biomass-Derived Butanediols over Rare Earth Zirconate Catalysts

Catalysts ◽

10.3390/catal10121392 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1392

Author(s):

Asami Matsuda ◽

Yoshitaka Matsumura ◽

Kazuki Nakazono ◽

Fumiya Sato ◽

Ryoji Takahashi ◽

...

Keyword(s):

Rare Earth ◽

Flow Reactor ◽

Rare Earth Metals ◽

Fluorite Structure ◽

Catalytic Performance ◽

High Specific Surface Area ◽

Heavy Rare Earth ◽

High Crystallinity ◽

Unsaturated Alcohols ◽

Selective Formation

The aim of this work is to develop an effective catalyst for the conversion of butanediols, which is derivable from biomass, to valuable chemicals such as unsaturated alcohols. The dehydration of 1,4-, 1,3-, and 2,3-butanediol to form unsaturated alcohols such as 3-buten-1-ol, 2-buten-1-ol, and 3-buten-2-ol was studied in a vapor-phase flow reactor over sixteen rare earth zirconate catalysts at 325 °C. Rare earth zirconates with high crystallinity and high specific surface area were prepared in a hydrothermal treatment of co-precipitated hydroxide. Zirconates with heavy rare earth metals, especially Y2Zr2O7 with an oxygen-defected fluorite structure, showed high catalytic performance of selective dehydration of 1,4-butanediol to 3-buten-1-ol and also of 1,3-butanediol to form 3-buten-2-ol and 2-buten-1-ol, while the zirconate catalysts were less active in the dehydration of 2,3-butanediol. The calcination of Y2Zr2O7 significantly affected the catalytic activity of the dehydration of 1,4-butanediol: a calcination temperature of Y2Zr2O7 at 900 °C or higher was efficient for selective formation of unsaturated alcohols. Y2Zr2O7 with high crystallinity exhibits the highest productivity of 3-buten-1-ol from 1,4-butanediol at 325 °C.

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The Effect of Rare Earth Modification on the Structure and Catalytic Performance of SO42-/ZrO2 Solid Acid Catalysts

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.1375 ◽

2011 ◽

Vol 287-290 ◽

pp. 1375-1378

Author(s):

Ying Chen ◽

Bao Hui Wang ◽

Xue Sun ◽

Hui Li

Keyword(s):

Rare Earth ◽

Solid Acid ◽

Tetragonal Zirconia ◽

Acid Methyl Ester ◽

Catalytic Performance ◽

Solid Acid Catalysts ◽

Acid Catalysts ◽

X Ray Diffraction ◽

Ft Ir ◽

Xrd Patterns

Rare earth modified SO2-4/ZrO2 solid acid catalysts were prepared by coprecipitation and impregnation methods respectively. The properties of the samples were characterized by XRD (X-ray diffraction), FT-IR (Fourier transform infrared spectroscopy). And their catalytic performances were evaluated and investigated by transesterification of waste oil with methanol. The results showed that the catalyst containing 4% Ce and calcined at 550°C displayed the highest production rate and the better reuse ability than the others. 63.5% yield of fatty acid methyl ester was achieved. An analysis of XRD patterns reveal that the incorporation of rare earth into tetragonal zirconia stabilizes the compound, and the calcination at 550°C increases the reactivity of the catalyst by producing a greater fraction of active tetragonal zirconia. It can be seen from the FT-IR spectra that superacids structures are formed in the catalysts and the acidity is strengthened remarkably and the activated centre of the catalyst were increasesed.

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Photodegradation Studies on Orange G and Acid Blue 113: New Doped Rare Earth Nanometal Oxides as Visible Light Active Photo Catalyst

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.938.257 ◽

2014 ◽

Vol 938 ◽

pp. 257-262

Author(s):

G.A. Suganya Josephine ◽

Arumugam Sivasamy

Keyword(s):

Rare Earth ◽

Visible Light ◽

Kinetic Studies ◽

Degradation Process ◽

Oh Radicals ◽

Time Duration ◽

Ph Variation ◽

Orange G ◽

Acid Blue 113 ◽

Acid Blue

Dyes are a source of serious pollutants from different industrial outlets and show a major contribution in polluting the environment. In the present study two dyes namely Orange G and Acid Blue 113 were compared for their photodegradation efficiency employing rare earth nanometal oxide as a visible active photocatalyst. The prepared catalyst was nanocrystalline form with particle size 70 nm and the surface of the catalyst was highly porous and rough which facilitates the absorption of the dye further enhance the photo degradation which were confirmed by various characterization techniques. Effect of pH, variation of catalyst dosage, variation of initial dye concentration and kinetic studies were conducted for both the dyes. The reaction followed a pseudo first order kinetics. The activity of the prepared catalyst was higher when compared to a commercially used metal oxide. Reusability studies proved that the catalyst prepared was very active even upto the third cycle. The degradation process was initiated by the attack of the OH radical generated in the in-situ process via visible light irradiation. EPR spin trapping technique was employed to confirm the presence of OH radicals. The prepared catalyst degraded the dye molecules of interest in lesser time duration by absorption of visible light, thereby reducing the cost of photodegradation.

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