scholarly journals Enhancing Photocatalytic Degradation of Methyl Blue Using PVP-Capped and Uncapped CdSe Nanoparticles

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Kgobudi Frans Chepape ◽  
Thapelo Prince Mofokeng ◽  
Pardon Nyamukamba ◽  
Kalenga Pierre Mubiayi ◽  
Makwena Justice Moloto
Keyword(s):  
Photocatalytic Degradation ◽  
Reduction Method ◽  
Organic Dyes ◽  
Chemical Reduction ◽  
Cdse Nanoparticles ◽  
Methyl Blue ◽  
Simple Type ◽  
Chemical Reduction Method ◽  
Tem Analysis ◽  
Transmission Electron

Quantum confinement of semiconductor nanoparticles is a potential feature which can be interesting for photocatalysis, and cadmium selenide is one simple type of quantum dot to use in the following photocatalytic degradation of organic dyes. CdSe nanoparticles capped with polyvinylpyrrolidone (PVP) in various concentration ratios were synthesized by the chemical reduction method and characterized. The transmission electron microscopy (TEM) analysis of the samples showed that 50% PVP-capped CdSe nanoparticles were uniformly distributed in size with an average of 2.7 nm and shape which was spherical-like. The photocatalytic degradation of methyl blue (MB) in water showed efficiencies of 31% and 48% when using uncapped and 50% PVP-capped CdSe nanoparticles as photocatalysts, respectively. The efficiency of PVP-capped CdSe nanoparticles indicated that a complete green process can be utilized for photocatalytic treatment of water and waste water.

Preparation of Fe3O4-Coated Microsilica Composites via Chemical Reduction Method

2013 ◽  
Vol 750-752 ◽  
pp. 1071-1074
Author(s):  
Hui Xia Feng ◽  
Bai Yi Chen ◽  
De Yi Zhang ◽  
Jian Qiang Zhang ◽  
He Ming Luo
Keyword(s):  
Electron Microscope ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Vibrating Sample Magnetometer ◽  
Chemical Reduction Method ◽  
Magnetic Composites ◽  
X Ray ◽  
The Core ◽  
Transmission Electron ◽  
Novel Method

Fe3O4-coated microsilica composites were synthesized by a novel method. The struction like precursor Fe3O4 nanoparticles as the shell and microsillica as the core for the composite has been prepared by chemical reduction method. The Fe3O4-coated microsilica composite presents a saturation magnetization value of 38.03 emu/g, which is sufficient to complete magnetic separation. The synthesized magnetic composites are characterized by X-ray diffractometer (XRD), transmission electron microscope (TEM) and vibrating sample magnetometer (VSM). The results indicated that Fe3O4 nanoparticles successfully coated on microsilica.

Preparation of Nano-Ru/[Bmim][BF4] Catalyst and its Application in the Benzene Selective Hydrogenation

2011 ◽  
Vol 110-116 ◽  
pp. 1906-1911 ◽  
Author(s):  
Jun Fang Wei ◽  
Yan Ji Wang ◽  
Juan Li ◽  
Wei Xue
Keyword(s):  
Ionic Liquids ◽  
Selective Hydrogenation ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Chemical Reduction Method ◽  
Tem Analysis ◽  
Hydrogenation Activity

The nano-Ru/[Bmim][BF4] catalyst was prepared for benzene selective hydrogenation in 1-n-butyl-3- methylimidazolium tetrafluoroborate [Bmim][BF4] by chemical reduction method. TEM analysis of these nanoparticles sho wed the monodisperse Ru0particles which were prepared by positive dropping method dispersed in the ionic liquids with diameters less than 5nm. The Ru0particles which were prepared by reverse dropping method agglomerated with diameters more than 10nm. KBH4was the suitable reductant. The optimum loading of Ru was 1.5%. The hydrogenation activity of Ru/ [Bmim] [BF4] was high and the selectivity of cyclohexene was very low. Selectivity of cyclohexene was only 14.5% at 27.3 % benzene conversion.

Fast and Simple Fabrication of RGO/Ag Nanocomposite with Homogenous Dispersion

2013 ◽  
Vol 328 ◽  
pp. 674-678
Author(s):  
Xiao Juan Jiang ◽  
Guo Qiang Luo ◽  
Mei Juan Li ◽  
Qiang Shen ◽  
Lian Meng Zhang
Keyword(s):  
Fourier Transform ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Transmission Electron Microscope ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Chemical Reduction Method ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

The RGO/Ag nanocomposite with a homogeneous dispersion of Ag on the surface of RGO has been successfully prepared via situ chemical reduction method using DMF (dimethylformamide) as solvent and reducing agent. The RGO/Ag nanocomposite was characterized by X-ray diffractometer (XRD), Fourier transform-infrared (FTIR) spectra, Fieldemission scanning electron microscope (FESEM) and transmission electron microscope (TEM). It is suggested that in the presence of the PVP (polyvinylpyrrolidone), the electrostatic attraction of Ag+ions with negative GO sheets lead to the decoration of Ag nanoparticles on the surface of RGO sheets in RGO/Ag nanocomposite.

scholarly journals Glycerol Valorization over ZrO2-Supported Copper Nanoparticles Catalysts Prepared by Chemical Reduction Method

Catalysts ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1040
Author(s):  
Juan Garcés ◽  
Ramón Arrué ◽  
Néstor Novoa ◽  
Andreia F. Peixoto ◽  
Ricardo J. Chimentão
Keyword(s):  
Copper Nanoparticles ◽  
Reduction Method ◽  
Chemical Reduction ◽  
X Ray Diffraction ◽  
Chemical Reduction Method ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Region I ◽  
Temperature Programmed

Copper nanoparticles (NPs) and ZrO2-supported copper NPs (Cu NPs/ZrO2) were synthesized via a chemical reduction method applying different pH (4, 7 and 9) and evaluated in a glycerol dehydration reaction. Copper NPs were characterized with transmission electron microscopy (TEM) and UV–vis spectroscopy. Transmission electron microcopy (TEM) results revealed a homogeneous distribution of copper NPs. A hypsochromic shift was identified with UV–vis spectroscopy as the pH of the synthesis increased from pH = 4 to pH = 9. Zirconia-supported copper NPs catalysts were characterized using N2 physisorption, X-ray diffraction (XRD), TEM, X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR), temperature-programmed desorption of ammonia (NH3-TPD) and N2O chemisorption. The presence of ZrO2 in the chemical reduction method confirmed the dispersion of the copper nanoparticles. X-ray diffraction indicated only the presence of tetragonal zirconia patterns in the catalysts. XPS identified the Cu/Zr surface atomic ratio of the catalysts. TPR patterns showed two main peaks for the Cu NPS/ZrO2 pH = 9 catalyst; the first peak between 125 and 180 °C (region I) was ascribed to more dispersed copper species, and the second one between 180 and 250 °C (region II) was assigned to bulk CuO. The catalysts prepared at pH = 4 and pH = 7 only revealed reduction at lower temperatures (region I). Copper dispersion was determined by N2O chemisorption. With NH3-TPD it was found that Cu NPs/ZrO2 pH = 9 exhibited the highest total quantity of acidic sites and the highest apparent kinetic constant, with a value of 0.004 min−1. The different pH applied to the synthesis media of the copper nanoparticles determined the resultant copper dispersion on the ZrO2 support, providing active domains for glycerol conversion.

Formation of Platinum Nanodendrites Embedded Organic Insulator for Memory Application

2014 ◽  
Vol 1024 ◽  
pp. 44-47 ◽  
Author(s):  
Nur Syafinaz Ridhuan ◽  
Nabil Iman Muzzafaruddin ◽  
Abdul Razak Khairunisak ◽  
K.C. Aw
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Chemical Reduction Method ◽  
Growth Duration ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Memory Characteristics

This work describes the formation of platinum nanodendrites (PtNDs) using the chemical reduction method. The PtNDs were formed with varying concentration of K2PtCl4 precursor (5-20 mM) and growth duration (8-16 min). The optimum concentration of K2PtCl4 was 15 mM whereby high crystalline nanodendrites with an average size of 118 nm were produced. Aggregation of nanodendrites occurred when the growth duration was prolonged to more than 12 minutes. The morphology and size of PtNDs were characterized by using a transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM) and X-ray diffractometer (XRD). Additionally, the memory characteristics of PtNDs embedded in polymethylsilsesquioxanes (PMSSQ)/Si with gold electrodes were studied in this work. PtNDs played a role as charge-trapped sites and showed good memory effect when embedded in PMSSQ. Optimum memory properties of PMSSQ-embedded PtNDs were obtained for PtNDs synthesized with 15 mM K2PtCl4 concentration at 12 min of growth duration with 170 electrons trapped per PtNDs and Vth of 2.8 V.

scholarly journals FusariumAntifungal Activities of Copper Nanoparticles Synthesized by a Chemical Reduction Method

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Pham Van Viet ◽  
Hai Thi Nguyen ◽  
Thi Minh Cao ◽  
Le Van Hieu
Keyword(s):  
Copper Nanoparticles ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Fungal Growth ◽  
Spherical Shape ◽  
Xrd Analysis ◽  
Chemical Reduction Method ◽  
Transmission Electron ◽  
Ft Ir ◽  
Average Size

We report on the process of synthesizing copper nanoparticles (Cu Nps) for a short reactive time by chemical reduction method with a support of CTAB reductive agent. Their properties were determined by ultraviolet-visible (UV-Vis) absorption spectrum, the X-ray (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), and Transmission Electron Microscopy (TEM) images. The antifungal activity of Cu Nps was evaluated by testing againstFusariumsp. The Cu Nps were obtained with the average size in the range of 20–50 nm having spherical shape. The survey shows that when Cu Nps were used at 450 ppm concentration in 9-day incubation, 93.98% of fungal growth was inhibited.

Effective and viable photocatalytic degradation of Rhodamine B dye in aqueous media using CuO/PVA Nanocomposites

2021 ◽  
Author(s):  
Zaheer Ahmed ◽  
Ghulam Qadir Shar ◽  
Aamna Balouch ◽  
Abdul Hameed Pato ◽  
Abdul Rauf Shaikh
Keyword(s):  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Heterogeneous Catalysts ◽  
Reduction Method ◽  
Chemical Reduction ◽  
Aqueous Media ◽  
Nano Composites ◽  
Chemical Reduction Method ◽  
Rhodamine B Dye ◽  
Multiple Recycling

Nowadays, Heterogeneous catalysts are preferable to homogeneous to get more socioeconomic assistance because of multiple recycling. In the current study, The CuO/PVA nano composites were synthesized via chemical reduction method...

Antimicrobial Activity of Silver Nanoparticles Prepared Under an Ultrasonic Field

2011 ◽  
Vol 4 (3) ◽  
pp. 1491-1496
Author(s):  
Umadevi M ◽  
Rani T ◽  
Balakrishnan T ◽  
Ramanibai R
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Reduction Method ◽  
Therapeutic Potential ◽  
Chemical Reduction ◽  
Ultrasonic Field ◽  
Great Promise ◽  
Chemical Reduction Method ◽  
E Coli

Nanotechnology has great promise for improving the therapeutic potential of medicinal molecules and related agents. In this study, silver nanoparticles of different sizes were synthesized in an ultrasonic field using the chemical reduction method with sodium borohydride as a reducing agent. The size effect of silver nanoparticles on antimicrobial activity were tested against the microorganisms Staphylococcus aureus (MTCC No. 96), Bacillus subtilis (MTCC No. 441), Streptococcus mutans (MTCC No. 497), Escherichia coli (MTCC No. 739) and Pseudomonas aeruginosa (MTCC No. 1934). The results shows that B. subtilis, and E. coli were more sensitive to silver nanoparticles and its size, indicating the superior antimicrobial efficacy of silver nanoparticles. 

scholarly journals Synthesis of Cu core Ag shell nanoparticles using chemical reduction method

2015 ◽  
Vol 6 (2) ◽  
pp. 025018 ◽  
Author(s):  
Dung Chinh Trinh ◽  
Thi My Dung Dang ◽  
Kim Khanh Huynh ◽  
Eric Fribourg-Blanc ◽  
Mau Chien Dang
Keyword(s):  
Reduction Method ◽  
Chemical Reduction ◽  
Chemical Reduction Method ◽  
Shell Nanoparticles
Sign in / Sign up

Export Citation Format

Share Document