Non-Enzymatic Glucose Sensing Based on Incorporation of Carbon Nanotube into Zn-Co-S Ball-in-Ball Hollow Sphere

Zn-Co-S ball-in-ball hollow sphere (BHS) was successfully prepared by solvothermal sulfurization method. An efficient strategy to synthesize Zn-Co-S BHS consisted of multilevel structures by controlling the ionic exchange reaction was applied to obtain great performance electrode material. Carbon nanotubes (CNTs) as a conductive agent were uniformly introduced with Zn-Co-S BHS to form Zn-Co-S BHS/CNTs and expedited the considerable electrocatalytic behavior toward glucose electro-oxidation in alkaline medium. In this study, characterization with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) was used for investigating the morphological and physical/chemical properties and further evaluating the feasibility of Zn-Co-S BHS/CNTs in non-enzymatic glucose sensing. Electrochemical methods (cyclic voltammetry (CV) and chronoamperometry (CA)) were performed to investigate the glucose sensing performance of Zn-Co-S BHS/CNTs. The synergistic effect of Faradaic redox couple species of Zn-Co-S BHS and unique conductive network of CNTs exhibited excellent electrochemical catalytic ability towards the glucose electro-oxidation, which revealed linear range from 5 to 100 μM with high sensitivity of 2734.4 μA mM−1 cm−2, excellent detection limit of 2.98 μM, and great selectivity in the presence of dopamine, uric acid, ascorbic acid, and fructose. Thus, Zn-Co-S BHS/CNTs would be expected to be a promising material for non-enzymatic glucose sensing.

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3D Modeling of Silver Doped ZrO2 Coupled Graphene-Based Mesoporous Silica Quaternary Nanocomposite for a Nonenzymatic Glucose Sensing Effects

Nanomaterials ◽

10.3390/nano12020193 ◽

2022 ◽

Vol 12 (2) ◽

pp. 193

Author(s):

Kamrun Nahar Fatema ◽

Chang-Sung Lim ◽

Yin Liu ◽

Kwang-Youn Cho ◽

Chong-Hun Jung ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Mesoporous Silica ◽

Photoelectron Spectroscopy ◽

Glucose Sensor ◽

Diffuse Reflectance Spectroscopy ◽

Active Material ◽

Glucose Sensing ◽

X Ray ◽

Transmission Electron

We described the novel nanocomposite of silver doped ZrO2 combined graphene-based mesoporous silica (ZrO2-Ag-G-SiO2,) in bases of low-cost and self-assembly strategy. Synthesized ZrO2-Ag-G-SiO2 were characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, Nitrogen adsorption-desorption isotherms, X-ray photoelectron spectroscopy (XPS), and Diffuse Reflectance Spectroscopy (DRS). The ZrO2-Ag-G-SiO2 as an enzyme-free glucose sensor active material toward coordinate electro-oxidation of glucose was considered through cyclic voltammetry in significant electrolytes, such as phosphate buffer (PBS) at pH 7.4 and commercial urine. Utilizing ZrO2-Ag-G-SiO2, glucose detecting may well be finished with effective electrocatalytic performance toward organically important concentrations with the current reaction of 9.0 × 10−3 mAcm−2 and 0.05 mmol/L at the lowest potential of +0.2 V, thus fulfilling the elemental prerequisites for glucose detecting within the urine. Likewise, the ZrO2-Ag-G-SiO2 electrode can be worked for glucose detecting within the interferometer substances (e.g., ascorbic corrosive, lactose, fructose, and starch) in urine at proper pH conditions. Our results highlight the potential usages for qualitative and quantitative electrochemical investigation of glucose through the ZrO2-Ag-G-SiO2 sensor for glucose detecting within the urine concentration.

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Characterization of Y/TiO2 Nanoparticles and their Reactivity for CO2 Photoreduction

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.55-57.1506 ◽

2011 ◽

Vol 55-57 ◽

pp. 1506-1510 ◽

Cited By ~ 3

Author(s):

Jing Wei ◽

Xin Tan ◽

Tao Yu ◽

Lin Zhao

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Chemical Properties ◽

X Ray Diffraction ◽

X Ray ◽

Uv Illumination ◽

Transmission Electron ◽

And Chemical Properties

A series of Y/TiO2nanoparticles (NPs) were synthesized via sol-gel method. The crystal structures, morphologies and chemical properties were characterized using X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). We investigated the effects of different doping amounts of Y on the reaction of CO2photoreduction. The results shown that 0.1 wt.%Y/TiO2(0.1YT) performed the highest photocatalytic activity, which yielded 384.62 µmol/g∙cat. formaldehyde after 6 h of UV illumination.

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Nanostructured Materials for Food Applications: Spectroscopy, Microscopy and Physical Properties

Bioengineering ◽

10.3390/bioengineering6010026 ◽

2019 ◽

Vol 6 (1) ◽

pp. 26 ◽

Cited By ~ 16

Author(s):

Shubham Sharma ◽

Swarna Jaiswal ◽

Brendan Duffy ◽

Amit Jaiswal

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Nanostructured Materials ◽

Photoelectron Spectroscopy ◽

Chemical Properties ◽

Nanostructured Material ◽

Correlation Spectroscopy ◽

Spectroscopic Techniques ◽

X Ray ◽

Transmission Electron

Nanotechnology deals with matter of atomic or molecular scale. Other factors that define the character of a nanoparticle are its physical and chemical properties, such as surface area, surface charge, hydrophobicity of the surface, thermal stability of the nanoparticle and its antimicrobial activity. A nanoparticle is usually characterized by using microscopic and spectroscopic techniques. Microscopic techniques are used to characterise the size, shape and location of the nanoparticle by producing an image of the individual nanoparticle. Several techniques, such as scanning electron microscopy (SEM), transmission electron microscopy/high resolution transmission electron microscopy (TEM/HRTEM), atomic force microscopy (AFM) and scanning tunnelling microscopy (STM) have been developed to observe and characterise the surface and structural properties of nanostructured material. Spectroscopic techniques are used to study the interaction of a nanoparticle with electromagnetic radiations as the function of wavelength, such as Raman spectroscopy, UV–Visible spectroscopy, attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), dynamic light scattering spectroscopy (DLS), Zeta potential spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray photon correlation spectroscopy. Nanostructured materials have a wide application in the food industry as nanofood, nano-encapsulated probiotics, edible nano-coatings and in active and smart packaging.

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Facile Preparation of Carbon Nitride-ZnO Hybrid Adsorbent for CO2 Capture: The Significant Role of Amine Source to Metal Oxide Ratio

Catalysts ◽

10.3390/catal11101253 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1253

Author(s):

Siti Aishah Anuar ◽

Khairul Naim Ahmad ◽

Ahmed Al-Amiery ◽

Mohd Shahbudin Masdar ◽

Wan Nor Roslam Wan Isahak

Keyword(s):

Electron Microscopy ◽

Metal Oxide ◽

Photoelectron Spectroscopy ◽

Physical Adsorption ◽

Synthesis Method ◽

Chemical Properties ◽

Gaseous Fuel ◽

X Ray ◽

Transmission Electron ◽

Adsorption Analysis

The presence of CO2 in gaseous fuel and feedstock stream of chemical reaction was always considered undesirable. High CO2 content will decrease quality and heating value of gaseous fuel, such as biohydrogen, which needs a practical approach to remove it. Thus, this work aims to introduce the first C3N4-metal oxide hybrid for the CO2 cleaning application from a mixture of CO2-H2 gas. The samples were tested for their chemical and physical properties, using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), physical adsorption analysis (BET), fourier-transform infrared (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The CO2 capacity test was carried out by means of a breakthrough test at 1 atm and 25° C using air as a desorption system. Among the samples, amine/metal oxide mass ratio of 2:1 (CNHP500-2(2-1)) showed the best performance of 26.9 wt. % (6.11 mmol/g), with a stable capacity over 6 consecutive cycles. The hybrid sample also showed 3 times better performance than the raw C3N4. In addition, it was observed that the hydrothermal C3N4 synthesis method demonstrated improved chemical properties and adsorption performance than the conventional dry pyrolysis method. In summary, the performance of hybrid samples depends on the different interactive factors of surface area, pore size and distribution, basicity, concentration of amine precursors, ratio of amines precursors to metal oxide, and framework stability.

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HYDROTHERMAL SYNTHESIS OF α-MoO3 NANORODS FOR NO2 DETECTION

International Journal of Nanoscience ◽

10.1142/s0219581x12400443 ◽

2012 ◽

Vol 11 (06) ◽

pp. 1240044 ◽

Cited By ~ 5

Author(s):

SHOULI BAI ◽

SONG CHEN ◽

YUAN TIAN ◽

RUIXIAN LUO ◽

DIANQING LI ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Molybdenum Trioxide ◽

Hydrothermal Process ◽

High Sensitivity ◽

X Ray Diffraction ◽

Hydrothermal Temperature ◽

X Ray ◽

Transmission Electron ◽

Ft Ir

Thermodynamically stable molybdenum trioxide nanorods have been successfully synthesized by a simple hydrothermal process. The product exhibits high-quality, single-crystalline layered orthorhombic structure (α- MoO3 ), and aspect ratio over 20 by characterizations of X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and Fourier transform infrared (FT-IR). The growth mechanism of α- MoO3 nanorods can be understood by electroneutral and dehydration reaction, which is highly dependent on solution acidity and hydrothermal temperature. The sensing tests show that the sensor based on MoO3 nanorods exhibits high sensitivity to NO2 and is not interferred by CO and CH4 , which makes this kind sensor a competitive candidate for NO2 detection. The intrinsic sensing performance of MoO3 maybe arise from its nonstoichiometry of MoO3 owing to the presence of Mo5+ and oxygen vacancy in MoO3 lattice, which has been confirmed by X-ray photoelectron spectroscopy (XPS) analysis. The sensing mechanism of MoO3 for NO2 is also discussed.

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Novel 3D Structure of Silver Doped ZrO2 Combined Graphene-Based Mesopouros Silica Quaternary Nanocomposite for a Nonenzymatic Glucose Sensing Effects

10.21203/rs.3.rs-546682/v1 ◽

2021 ◽

Author(s):

Won-Chun Oh ◽

Kwang-Youn Cho ◽

Saksit Chanthai ◽

Kamrun Nahar Fatema

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Glucose Sensor ◽

Diffuse Reflectance Spectroscopy ◽

Active Material ◽

3D Structure ◽

Glucose Sensing ◽

X Ray ◽

Transmission Electron

Abstract We described the novel nanocomposite of silver doped ZrO2 combined graphene-based mesoporous silica (ZrO2-Ag-G-SiO2, ZAGS) in bases of low-cost and self-assembly strategy. Synthesized ZAGS were characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), Raman spectroscopy, Nitrogen adsorption-desorption isotherms, X-ray photoelectron spectroscopy (XPS), and Diffuse Reflectance Spectroscopy (DRS). The ZAGS as a enzyme-free glucose sensor active material toward coordinate electro-oxidation of glucose was considered through cyclic voltammetry in significant organic electrolytes, such as phosphate-buffer (PBS) at pH 7.4 and commercial urine. Utilizing ZAGS, glucose detecting may well be finished with effective electrocatalytic performance toward organically important concentrations with the current reaction of 9.0 × 10-3 mAcm-2 and discovery restrain of 0.05 mmol/L at the lowest potential of +0.2 V, thus fulfilling the elemental prerequisites for glucose detecting within the urine. Likewise, ZAGS cathodes can be worked for glucose detecting within the nearness of interferometer substances (e.g., ascorbic corrosive, lactose and starch) in urine at proper pH condition. Our results highlight the potential usages for subjective and quantitative electrochemical investigation of glucose through the ZAGS sensor for glucose detecting stage permitted within the urine concentration.

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Synthesis of Ce1−xPdxO2−δ Solid Solution in Molten Nitrate

Catalysts ◽

10.3390/catal10060640 ◽

2020 ◽

Vol 10 (6) ◽

pp. 640

Author(s):

Hideaki Sasaki ◽

Keisuke Sakamoto ◽

Masami Mori ◽

Tatsuaki Sakamoto

Keyword(s):

Electron Microscopy ◽

Solid Solution ◽

Solid Solutions ◽

Photoelectron Spectroscopy ◽

Synthesis Method ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Co Precipitation ◽

Ionic States

CeO2-based solid solutions in which Pd partially substitutes for Ce attract considerable attention, owing to their high catalytic performances. In this study, the solid solution (Ce1−xPdxO2−δ) with a high Pd content (x ~ 0.2) was synthesized through co-precipitation under oxidative conditions using molten nitrate, and its structure and thermal decomposition were examined. The characteristics of the solid solution, such as the change in a lattice constant, inhibition of sintering, and ionic states, were examined using X-ray diffraction (XRD), scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM−EDS), transmission electron microscopy (TEM)−EDS, and X-ray photoelectron spectroscopy (XPS). The synthesis method proposed in this study appears suitable for the easy preparation of CeO2 solid solutions with a high Pd content.

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Characterization of columns grown during KrF laser micromachining of Al2O3–TiC ceramics

Journal of Materials Research ◽

10.1557/jmr.2003.0154 ◽

2003 ◽

Vol 18 (5) ◽

pp. 1123-1130 ◽

Cited By ~ 6

Author(s):

V. Oliveira ◽

R. Vilar

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Laser Pulses ◽

Formation Mechanisms ◽

X Ray ◽

Reducing Conditions ◽

Transmission Electron ◽

Column Formation ◽

Krf Laser

This paper aims to contribute to the understanding of column formation mechanisms in Al2O3–TiC ceramics micromachined using excimer lasers. Chemical and structural characterization of columns grown in Al2O3–TiC composite processed with 200 KrF laser pulses at 10 J/cm2 was carried out by scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and x-ray diffraction analysis. Fully developed columns consist of a core of unprocessed material surrounded by an outer layer of Al2TiO5, formed in oxidizing conditions, and an inner layer, formed in reducing conditions, composed of TiC and Al3Ti or an AlTi solid solution. Possible mechanisms of column formation are discussed.

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Green Synthesis of Feather-Shaped MoS2/CdS Photocatalyst for Effective Hydrogen Production

International Journal of Photoenergy ◽

10.1155/2013/247516 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Yang Liu ◽

Hongtao Yu ◽

Xie Quan ◽

Shuo Chen

Keyword(s):

Electron Microscopy ◽

Hydrogen Production ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance ◽

Sulfur Source ◽

X Ray ◽

Transmission Electron ◽

Microscopy Images ◽

Effective Hydrogen ◽

Better Than

MoS2/CdS photocatalyst was fabricated by a hydrothermal method for H2production under visible light. This method used low toxic thiourea as a sulfur source and was carried out at 200°C. Thus, it was better than the traditional methods, which are based on an annealing process at relatively high temperature (above 400°C) using toxic H2S as reducing agent. Scanning electron microscopy and transmission electron microscopy images showed that the morphologies of MoS2/CdS samples were feather shaped and MoS2layer was on the surface of CdS. The X-ray photoelectron spectroscopy testified that the sample was composed of stoichiometric MoS2and CdS. The UV-vis diffuse reflectance spectra displayed that the loading of MoS2can enhance the optical absorption of MoS2/CdS. The photocatalytic activity of MoS2/CdS was evaluated by producing hydrogen. The hydrogen production rate on MoS2/CdS reached 192 μmol·h−1. This performance was stable during three repeated photocatalytic processes.

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Aluminum Nitride-Silicon Carbide Alloy Crystals Grown on SiC Substrates by Sublimation

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300000569 ◽

2005 ◽

Vol 10 ◽

Cited By ~ 6

Author(s):

Z. Gu ◽

L. Du ◽

J.H. Edgar ◽

E.A. Payzant ◽

L. Walker ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

Original Source ◽

X Ray ◽

Alloy Crystal ◽

Transmission Electron ◽

Crystal Substrate ◽

Vapor Distribution ◽

Uniform Composition

AlN-SiC alloy crystals, with a thickness greater than 500 µm, were grown on 4H- and 6H-SiC substrates from a mixture of AlN and SiC powders by the sublimation-recondensation method at 1860-1990 °C. On-axis SiC substrates produced a rough surface covered with hexagonal grains, while 6H- and 4H- off-axis SiC substrates with different miscut angles (8° or 3.68°) formed a relatively smooth surface with terraces and steps. The substrate misorientation ensured that the AlN-SiC alloy crystals grew two dimensionally as identified by scanning electron microscopy (SEM). X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed that the AlN-SiC alloys had the wurtzite structure. Electron probe microanalysis (EPMA) and x-ray photoelectron spectroscopy (XPS) demonstrated that the resultant alloy crystals had non-stoichiometric ratios of Al:N and Si:C and a uniform composition throughout the alloy crystal from the interface to the surface. The composition ratio of Al:Si of the alloy crystals changed with the growth temperature, and differed from the original source composition, which was consistent with the results predicted by thermodynamic calculation of the solid-vapor distribution of each element. XPS detected the bonding between Si-C, Si-N, Si-O for the Si 2p spectra. The dislocation density decreased with the growth, which was lower than 106 cm−2 at the alloy surface, more than two orders of magnitude lower compared to regions close to the crystal/substrate interface, as determined by TEM.

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