Synthesis of zirconia-based solid acid nanoparticles for fuel cell application

Zirconia nanoparticles were prepared by the precipitation and ageing methods. The precipitation method was performed by adding ammonium solution to the aqueous solution of zirconium chloride at room temperature. The ageing method was performed by leaving the precipitate formed in the mother liquor in the glass beaker for 48 hours at ambient temperatures. The nanoparticles from both methods were further sulphated and phosphated to increase their acid sites. The materials prepared were characterised by X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), Brunauer-EmmettTeller (BET), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) methods. The XRD results showed that the nanoparticles prepared by the precipitation method contained mixed phases of tetragonal and monoclinic phases, whereas the nanoparticles prepared by ageing method had only tetragonal phase. The TEM results showed that phosphated and sulphated zirconia nanoparticles obtained from the ageing method had a smaller particle size (10–12 nm) than the nanoparticles of approximately 25–30 nm prepared by precipitation only. The BET results showed that the ZrO2 nanoparticles surface area increased from 32 to 72 m2/g when aged.

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Enhanced Photocatalytic Activity of Cu2O Cabbage/RGO Nanocomposites under Visible Light Irradiation

Polymers ◽

10.3390/polym13111712 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1712

Author(s):

Appusamy Muthukrishnaraj ◽

Salma Ahmed Al-Zahrani ◽

Ahmed Al Otaibi ◽

Semmedu Selvaraj Kalaivani ◽

Ayyar Manikandan ◽

...

Keyword(s):

Electron Microscopy ◽

Thermo Gravimetric Analysis ◽

Visible Region ◽

Catalytic Performance ◽

Precipitation Method ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Dye Pollutants ◽

Transmission Electron

Towards the utilization of Cu2O nanomaterial for the degradation of industrial dye pollutants such as methylene blue and methyl orange, the graphene-incorporated Cu2O nanocomposites (GCC) were developed via a precipitation method. Using Hummers method, the grapheme oxide (GO) was initially synthesized. The varying weight percentages (1–4 wt %) of GO was incorporated along with the precipitation of Cu2O catalyst. Various characterization techniques such as Fourier-transform infra-red (FT-IR), X-ray diffraction (XRD), UV–visible diffused reflectance (UV-DRS), Raman spectroscopy, thermo gravimetric analysis (TGA), energy-dispersive X-ray analysis (EDX), and electro chemical impedance (EIS) were followed for characterization. The cabbage-like morphology of the developed Cu2O and its composites were ascertained from field-emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HR-TEM). In addition, the growth mechanism was also proposed. The results infer that 2 wt % GO-incorporated Cu2O composites shows the highest value of degradation efficiency (97.9% and 96.1%) for MB and MO at 160 and 220 min, respectively. Further, its catalytic performance over visible region (red shift) was also enhanced to an appreciable extent, when compared with that of other samples.

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Effect of ZrO2 Nanofiller on the Physical Properties of Epoxy Composites: Mechanical, Thermal and Dielectric

Jordan Journal of Physics ◽

10.47011/14.5.4 ◽

2021 ◽

Vol 14 (5) ◽

pp. 425-435

Keyword(s):

Thermal Analysis ◽

Differential Thermal Analysis ◽

Thermo Gravimetric Analysis ◽

Thermal Characteristics ◽

Zirconium Oxychloride ◽

Precipitation Method ◽

Zro2 Nanoparticles ◽

Gravimetric Analysis ◽

Thermo Gravimetric ◽

Zirconia Nanoparticles

Abstract: In this present work, Zirconia nanoparticles were prepared by precipitation method, Zirconium Oxychloride (ZrOCl2.8H2O) and ammonia (NH3) as starting materials. The synthesized Zirconia nanoparticles were characterized by XRD and the grain size in nanoscale was confirmed. The sheets of neat epoxy resin and epoxy with addition of ZrO2 nanoparticles are primed by solution casting method. The structures of epoxy polymer and hardener were found out using FTIR analysis. The thermal properties were analyzed using Thermo Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA). Thermo gravimetric analysis has been employed to investigate the thermal characteristics and their mode of thermal degradation. Differential thermal analysis has been used to determine the glass transition temperature of epoxy nanocomposites. The mechanical properties like tensile and flexural studies were analyzed and thus influences of nanofiller loading on these parameters were found to be very low. Keywords: Epoxy, ZrO2 nanoparticles, Nanocomposites, Thermal stability, Dielectric properties, Tensile strength, Flexural strength.

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Effect of Synthesis Temperature on Particles Size and Morphology of Zirconium Oxide Nanoparticle

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.50.18 ◽

2017 ◽

Vol 50 ◽

pp. 18-31 ◽

Cited By ~ 6

Author(s):

Rudzani Sigwadi ◽

Simon Dhlamini ◽

Touhami Mokrani ◽

Patrick Nonjola

Keyword(s):

Electron Microscopy ◽

Particle Size ◽

Zirconium Oxide ◽

Thermo Gravimetric Analysis ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Crystallite Sizes ◽

Ft Ir

The paper presents the synthesis and investigation of zirconium oxide (ZrO2) nanoparticles that were synthesised by precipitation method with the effects of the temperatures of reaction on the particles size, morphology, crystallite sizes and stability at high temperature. The reaction temperature effect on the particle size, morphology, crystallite sizes and stabilized a higher temperature (tetragonal and cubic) phases was studied. Thermal decomposition, band structure and functional groups were analyzed by Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Thermo-gravimetric analysis (TGA) and Fourier transform infrared (FT-IR). The crystal structure was determined using X-ray diffraction. The morphology and the particle size were studied using (SEM) and (TEM). The shaped particles were confirmed through the SEM analysis. The transmission electron microscopic analysis confirmed the formation of the nanoparticles with the particle size. The FT-IR spectra showed the strong presence of ZrO2 nanoparticles.

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Biosynthesis and Characterization of Copper Nanoparticles Using a Bioflocculant Extracted from Alcaligenis faecalis HCB2

Advanced Science Engineering and Medicine ◽

10.1166/asem.2019.2448 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1064-1070 ◽

Cited By ~ 4

Author(s):

Nkosinathi G. Dlamini ◽

Albertus K. Basson ◽

V. S. R. Rajasekhar Pullabhotla

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Copper Nanoparticles ◽

Average Particle Size ◽

Thermo Gravimetric Analysis ◽

Average Particle ◽

Gravimetric Analysis ◽

X Ray ◽

Transmission Electron ◽

Ft Ir

Bioflocculant from Alcaligenis faecalis HCB2 was used in the eco-friendly synthesis of the copper nanoparticles. Nanoparticles were characterized using a scanning electron microscope (SEM), transmission electron microscopy (TEM), UV-visible spectroscopy, thermo gravimetric analysis (TGA) and Fourier Transform Infrared Spectroscopy (FT-IR). The transmission electron microscopy images showed close to spherical shapes with an average particle size of ∼53 nm. Energy-dispersive X-ray spectroscopy analysis confirmed the presence of the Cu nanopartilces and also the other elements such as O, C, P, Ca, Cl, Na, K, Mg, and S originated from the bioflocculant. FT-IR results showed the presence of the –OH and –NH2 groups, aliphatic bonds, amide and Cu–O bonds. Powder X-ray diffraction peaks confirmed the presence of (111) and (220) planes of fcc structure at 2 of 33° and 47° respectively with no other impurity peaks.

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Chitosan-Grafted Halloysite Nanotubes-Fe3O4 Composite for Laccase-Immobilization and Sulfamethoxazole-Degradation

Polymers ◽

10.3390/polym12102221 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2221 ◽

Cited By ~ 2

Author(s):

Avinash A. Kadam ◽

Surendra K. Shinde ◽

Gajanan S. Ghodake ◽

Ganesh D. Saratale ◽

Rijuta G. Saratale ◽

...

Keyword(s):

Electron Microscopy ◽

Cost Effective ◽

Halloysite Nanotubes ◽

Environmental Pollutant ◽

Precipitation Method ◽

Gravimetric Analysis ◽

Immobilized Laccase ◽

Transmission Electron ◽

Laccase Immobilization ◽

And Storage

A surface-engineered nano-support for enzyme laccase-immobilization was designed by grafting the surface of halloysite nanotubes (HNTs) with Fe3O4 nanoparticles and chitosan. Herein, HNTs were magnetized (HNTs-M) by a cost-effective reduction-precipitation method. The synthesized HNTs-M were grafted with 0.25%, 0.5%, 1%, and 2% chitosan (HNTs-M-chitosan), respectively. Synthesized HNTs-M-chitosan (0.25%), HNTs-M-chitosan (0.5%), HNTs-M-chitosan (1%) and HNTs-M-chitosan (2%) were linked with glutaraldehyde (GTA) for laccase immobilization. Among these formulations, HNTs-M-chitosan (1%) exhibited the highest laccase immobilization with 95.13% activity recovery and 100.12 mg/g of laccase loading. The optimized material was characterized thoroughly by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray powder diffraction (XRD), thermal gravimetric analysis (TGA), and vibrating sample magnetometer (VSM) analysis. The immobilized laccase (HNTs-M-chitosan (1%)-GTA-Laccase) exhibited higher pH, temperature, and storage stabilities. The HNTs-M-chitosan (1%)-GTA-Laccase possesses excellent reusability capabilities. At the end of 10 cycles of the reusability experiment, HNTs-M-chitosan (1%)-GTA-Laccase retained 59.88% of its initial activity. The immobilized laccase was utilized for redox-mediated degradation of sulfamethoxazole (SMX), resulting in 41%, 59%, and 62% degradation of SMX in the presence of 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), guaiacol (GUA), and syringaldehyde (SA), respectively. Repeated SMX degradation (57.10% after the sixth cycle) confirmed the potential of HNTs-M-chitosan (1%)-GTA-Laccase for environmental pollutant degradation. Thus, we successfully designed chitosan-based, rapidly separable super-magnetic nanotubes for efficacious enhancement of laccase biocatalysis, which can be applied as nano-supports for other enzymes.

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Preparation and Characterization of Poly(Dimethyl Diallyl Ammonium Chloride)/Modified SiO2 Spherical Brushes

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.731.569 ◽

2015 ◽

Vol 731 ◽

pp. 569-572 ◽

Cited By ~ 1

Author(s):

Na Su ◽

Zheng Min Cao

Keyword(s):

Electron Microscopy ◽

Ammonium Chloride ◽

Thermo Gravimetric Analysis ◽

Gel Permeation Chromatography ◽

Gravimetric Analysis ◽

Polyelectrolyte Brushes ◽

Transmission Electron ◽

Spherical Polyelectrolyte Brushes ◽

Trimethoxy Silane

Novel cationic spherical polyelectrolyte brushes (CSPB) consisting of γ-methacryloxypropyl trimethoxy-silane (KH-570) modified SiO2cores and poly (Dimethyl diallyl ammonium chloride) (PDMDAAC) brushes were prepared by conventional free radical polymerization. The resulting CSPB were characterized by Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and Thermo-gravimetric analysis (TGA). After cleaving the polyelectrolyte chains from the anchoring surface, the molecular weight of brushes was 1.824×103gmol-1from Gel Permeation Chromatography (GPC) measurements.

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THE SURFACE MODIFICATION OF CdSe–TGA QUANTUM DOTS WITH MULTIDENTATE BIOPOLYMER LIGAND BASED ON SALEP: AN EASY ROUTE FOR ENHANCING FLUORESCENCE INTENSITY

NANO ◽

10.1142/s1793292013500124 ◽

2013 ◽

Vol 08 (02) ◽

pp. 1350012

Author(s):

G. R. BARDAJEE ◽

F. MIZANI ◽

I. ROSTAMI ◽

Z. HOOSHYAR ◽

F. M. MINABIAN

Keyword(s):

Electron Microscopy ◽

Quantum Dots ◽

Surface Modification ◽

Fluorescence Intensity ◽

Thermo Gravimetric Analysis ◽

Gravimetric Analysis ◽

Cdse Qds ◽

Transmission Electron ◽

Before And After ◽

The Stability

The optical properties of CdSe quantum dots (QDs) capped by thioglycolic acid (TGA) before and after surface modification with poly (acrylic acid) grafted onto salep (salep-g-PAA), as a biopolymer-based multidentate ligand, were examined. The results showed that the fluorescence intensity as well as the stability of CdSe QDs was incredibly increased after surface modification with the biopolymer-based ligand. To provide more evidence for the occurrence of surface modification, the prepared CdSe –salep-g-PAA QDs were characterized by thermo-gravimetric analysis (TG), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR).

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Study of UV Stability and Physical Properties of Jute/Soy Flour Green Nanocomposites

Advances in Materials Science and Engineering ◽

10.33140/amse/02/01/02 ◽

2018 ◽

Vol 2 (1) ◽

Keyword(s):

Electron Microscopy ◽

Thermo Gravimetric Analysis ◽

Mechanical Tests ◽

Soy Flour ◽

Morphological Properties ◽

Gravimetric Analysis ◽

Transmission Electron ◽

Strong Interfacial Interaction ◽

The Matrix ◽

Ft Ir

Glutaraldehyde cross-linked jute fabric and soy flour was used to develop green nanocomposites via solution-induced intercalation method. The effect of TiO2 alone (TNP) and TiO2 in combination with nanoclay on the properties of the nanocomposites was studied. Fourier transfer infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffractrometry (XRD), and transmission electron microscopy (TEM) were used to examine the structural and morphological properties. They clearly revealed that both TNP and nanoclay were successfully loaded into the composite. The thermal and mechanical properties were determined using thermo gravimetric analysis (TGA), and mechanical tests, respectively. The study discloses noteworthy changes in the observed properties of the composites with inclusion of nanoparticles. Furthermore, in comparison to the unfilled composites, nanoparticles filled ones were found to exhibit much improved UV-resistance, flame retarding properties, and dimensional stability. The study revealed a strong interfacial interaction between the filler and the matrix within the prepared green nanocomposites.

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Precursor to High Purity Carbon Nanotubes: A Step by Step Evaluation of Carbon Yield

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.6.75 ◽

2009 ◽

Vol 6 ◽

pp. 75-87 ◽

Cited By ~ 2

Author(s):

K.N. Patil ◽

Chetan S. Solanki

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Thermo Gravimetric Analysis ◽

Gravimetric Analysis ◽

X Ray Diffraction ◽

Thermo Gravimetric ◽

Carrier Gas ◽

Transmission Electron ◽

Annealing Step ◽

Catalyst Type

Yield of carbon nanotubes (CNTs) depends on numerous process parameters such as temperature of synthesis, type of catalyst, type of precursor, time of precursor flow and partial pressure of precursor gas as well as carrier gas, etc. Experiments were performed in order to find the optimum temperature of synthesis for varying time of precursor flow. The yield was evaluated in terms of mass of crystalline CNTs per gram of substrate and/or catalyst. The CNTs were grown on a calcium carbonate (CaCO3) substrate, with iron-cobalt (Fe-Co) as a catalyst, using acetylene (C2H2) as a precursor gas and argon (Ar) as a carrier gas. A three-stage purification process, incorporating two acid treatment steps and one annealing step, was used for purification which ensures high grade purity of CNTs. The highest yield of 21.4 g of CNTs per g of catalyst was achieved at 700oC for 60 min of synthesis. The CNTs were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), Raman, Thermo-gravimetric analysis (TGA), and Gas chromatography (GC).

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SYNTHESIS AND CHARACTERIZATION OF Ba2SmSbO6 NANOPARTICLES

Modern Physics Letters B ◽

10.1142/s0217984907013420 ◽

2007 ◽

Vol 21 (19) ◽

pp. 1227-1234 ◽

Cited By ~ 3

Author(s):

C. VIJAYAKUMAR ◽

H. PADMA KUMAR ◽

JIJIMON K. THOMAS ◽

SAM SOLOMON ◽

S. U. K. NAIR ◽

...

Keyword(s):

Electron Microscopy ◽

Thermo Gravimetric Analysis ◽

Combustion Process ◽

Single Step ◽

Gravimetric Analysis ◽

Prepared Powder ◽

Auto Ignition ◽

Transmission Electron ◽

Calcination Step ◽

Phase Pure

Nanoparticles of samarium barium antimonate ( Ba 2 SmSbO 6), a complex perovskite has been synthesized using an auto-ignition combustion process for the first time. The nanoparticles thus obtained have been characterized using X-ray diffraction, thermo-gravimetric analysis, differential thermal analysis, Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. The XRD studies have shown that the as-prepared powder is phase pure Ba 2 SmSbO 6 and has a complex cubic perovskite ( A 2 BB ' O 6) crystalline structure with lattice constant a = 8.491 Å. The particle size of the as-prepared powder was in the range 20–50 nm. The nano crystals of Ba 2 SmSbO 6 synthesized by the combustion technique could be sintered to 97% of the theoretical density by heating at a temperature of 1550°C for 2 h. By the present combustion synthesis a phase pure Ba 2 SmSbO 6 nanopowder could be obtained by a single step process without the need of any calcination step.

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