Thermochromic and Femtosecond-Laser-Induced Damage Performance of Tungsten-Doped Vanadium Dioxide Films Prepared Using an Alloy Target

Thermochromic tungsten-doped VO2 thin films were successfully fabricated using a W-V alloy target. X-ray diffraction analyses showed that the W-doped VO2 film had a preferred orientation of (011), and that the doping did not degrade the film crystallinity compared with that of the pure film. X-ray photoelectron spectroscopy and energy-dispersive spectroscopy showed that the doped 0.81 atom% tungsten replaced vanadium in the lattice of the film. The metal–insulator transition temperature of the W-doped VO2 film was reduced to 35.5 °C, which is close to room temperature. Additionally, the infrared transmittance modulation of the W-doped film at λ = 2500 nm reached 56%, indicating an excellent switching efficiency. The damage behavior of the W-doped VO2 film under a femtosecond-laser irradiation was experimentally investigated. Our results revealed that defect-related damages induced by the femtosecond laser are relevant for W-doped VO2 films. This study provides valuable insights into VO2 films for potential applications in laser protection.

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Synthesis of Three-Dimensional Fe3O4/Graphene Aerogels for the Removal of Arsenic Ions from Water

Journal of Nanomaterials ◽

10.1155/2015/864864 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 10

Author(s):

Yan Ye ◽

Da Yin ◽

Bin Wang ◽

Qingwen Zhang

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

3D Structure ◽

Three Dimensional ◽

X Ray Diffraction ◽

X Ray ◽

Graphene Aerogels ◽

Transmission Electron ◽

Potential Applications ◽

Removal Of Arsenic

We report the synthesis of three-dimensional Fe3O4/graphene aerogels (GAs) and their application for the removal of arsenic (As) ions from water. The morphology and properties of Fe3O4/GAs have been characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and superconducting quantum inference device. The 3D nanostructure shows that iron oxide nanoparticles are decorated on graphene with an interconnected network structure. It is found that Fe3O4/GAs own a capacity of As(V) ions adsorption up to 40.048 mg/g due to their remarkable 3D structure and existence of magnetic Fe3O4nanoparticles for separation. The adsorption isotherm matches well with the Langmuir model and kinetic analysis suggests that the adsorption process is pseudo-second-ordered. In addition to the excellent adsorption capability, Fe3O4/GAs can be easily and effectively separated from water, indicating potential applications in water treatment.

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Low Cost Integrated Sensors Utilizing Patterned Nano-Structured Titania Arrays Fabricated Using a Simple Process

MRS Proceedings ◽

10.1557/proc-828-a7.5 ◽

2004 ◽

Vol 828 ◽

Author(s):

Zuruzi Abu Samah ◽

Andrei Kolmakov ◽

Martin Moskovits ◽

Noel C. MacDonald

Keyword(s):

Photoelectron Spectroscopy ◽

Low Cost ◽

Sol Gel ◽

X Ray Diffraction ◽

Aqueous Hydrogen Peroxide ◽

X Ray ◽

Sensing Systems ◽

Potential Applications ◽

Nano Wires ◽

Low Temperature Process

ABSTRACTUsing a novel low-temperature process, we demonstrate the facile integration of crack-free nanostructured titania (NST) as sensing elements in microsystems. Unlike conventional sol-gel methods, NST layers of interconnected nano-walls and nano-wires were formed by reacting Ti surfaces with aqueous hydrogen peroxide solution. Cracks were observed in NST layers formed on blanket Ti films but absent on arrays of patterned Ti pads below a threshold dimension. Analyses using TEM, high resolution SEM, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) reveal that NST consists of anatase TiO2 nano-crystals. NST pads were found able to detect oxygen gas of a few ppm. NST pad arrays were integrated on rigid and flexible substrates with potential applications in low cost and wearable sensing systems.

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SYNTHESIS, CHARACTERIZATION AND THE APPLICABILITY OF β-CYCLODEXTRINS FUNCTIONALIZED MESOPOROUS SBA-15 MOLECULAR SIEVES

NANO ◽

10.1142/s1793292013500501 ◽

2013 ◽

Vol 08 (05) ◽

pp. 1350050

Author(s):

MIN GUAN ◽

HAI-PENG BI ◽

ZUYUAN WANG ◽

SHAOHUA BU ◽

LING HUANG ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Molecular Sieves ◽

Nitrogen Adsorption ◽

X Ray Diffraction ◽

X Ray ◽

Adsorption Capacities ◽

Transmission Electron ◽

Potential Applications ◽

Adsorption Desorption

Mesoporous silicas SBA-15 are modified with β-Cyclodextrins (β-CD) by simple grafting method. β-CD functionalized SBA-15 was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), nitrogen adsorption–desorption measurements, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Furthermore, the applicability of it is investigated through studying the adsorption properties of clenbuterol. It showed better adsorption capacities of clenbuterol than pure SBA-15. β-CD functionalized SBA-15 material has the potential applications in the treatment of clenbuterol contamination in food and environment science.

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Nickel(II) cluster-based mixed-cation coordination polymer synthesized from 2-mercaptobenzoic acid and its application

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229619007368 ◽

2019 ◽

Vol 75 (7) ◽

pp. 877-882

Author(s):

Jingyan Zhu ◽

Shan Yan ◽

Hongping Xiao ◽

Jun Jiang ◽

Xinhua Li

Keyword(s):

Coordination Polymer ◽

Photoelectron Spectroscopy ◽

Functional Materials ◽

Discharge Process ◽

X Ray Diffraction ◽

X Ray ◽

Mixed Cation ◽

Chloride Hexahydrate ◽

Potential Applications ◽

Cation Coordination

High-nuclearity metal clusters have received considerable attention not only because of their diverse architectures and topologies, but also because of their potential applications as functional materials in many fields. To explore new types of clusters and their potential applications, a new nickel(II) cluster-based mixed-cation coordination polymer, namely poly[hexakis[μ4-(2-carboxylatophenyl)sulfanido]di-μ3-chlorido-tri-μ2-hydroxido-octanickel(II)sodium(I)], [Ni8NaCl2(OH)3(C7H4O2S)6] n , 1, was synthesized using nickel chloride hexahydrate and mercaptobenzoic acid (H2mba) as starting reactants under hydrothermal conditions. The material was characterized by single-crystal X-ray diffraction (SCXRD), Fourier transform IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction and X-ray photoelectron spectroscopy analysis. SCXRD shows that 1 consists of a hexanuclear nickel(II) [Ni6] cluster, dinuclear NiII nodes and a mononuclear NaI node, resulting in the formation of a complex covalent three-dimensional network. In addition, a tightly packed NiO/C&S nanocomposite is fabricated by sintering the coordination precursor at 400 °C. The uniform nanocomposite consists of NiO nanoparticles, incompletely carbonized carbon and incompletely vulcanized sulfur. When used as a supercapacitor electrode, the synthesized composite shows an extra-long cycling stability (>5000 cycles) during the charge/discharge process.

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Thin Films of Semiconducting SnSi Alloys Grown by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-358-775 ◽

1994 ◽

Vol 358 ◽

Author(s):

Randolph E. Treece ◽

J. S. Horwitz ◽

D. B. Chrisey ◽

J. Tang ◽

R. S. Williams

Keyword(s):

Pulsed Laser Deposition ◽

Photoelectron Spectroscopy ◽

Pulsed Laser ◽

Laser Deposition ◽

X Rays ◽

X Ray Diffraction ◽

Temperature Dependent ◽

Target Holder ◽

X Ray ◽

Potential Applications

ABSTRACTSemiconducting SnxSi1−x (0≤x≤0.6) thin-film alloys have been grown by pulsed laser deposition (PLD). These new materials are amorphous to X-rays and display small positive optical band gaps, suggesting potential applications in solar cells. The tin silicide films were grown by depositing very thin (1–30 Å) alternating atomic layers from individual Sn and Si targets utilizing an automated multi-target holder coupled to a conventional PLD system. The value of x was selected by controlling the thickness of the atomic layers. The films were characterized by X-ray diffraction, optical absorption, Rutherford backscattering spectroscopy, temperature-dependent resistivity, and X-ray photoelectron spectroscopy. Tin segregation is prevented by keeping the Sn layer thickness below a critical value. Compositions beyond x > 0.6 led to semimetallic SnxSi1−x films with tin crystallites.

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Structure and Photoluminescence Properties of Thermally Synthesized V2O5 and Al-Doped V2O5 Nanostructures

Materials ◽

10.3390/ma14020359 ◽

2021 ◽

Vol 14 (2) ◽

pp. 359

Author(s):

Chih-Chiang Wang ◽

Chia-Lun Lu ◽

Fuh-Sheng Shieu ◽

Han C. Shih

Keyword(s):

Photoelectron Spectroscopy ◽

Chemical Vapor ◽

Growth Direction ◽

Photoluminescence Intensity ◽

X Ray Diffraction ◽

Smart Windows ◽

X Ray ◽

Transmission Electron ◽

Potential Applications ◽

Li Ion

Al-free and Al-doped V2O5 nanostructures were synthesized by a thermal-chemical vapor deposition (CVD) process on Si(100) at 850 °C under 1.2 × 10−1 Torr via a vapor-solid (V-S) mechanism. X-ray diffraction (XRD), Raman, and high-resolution transmission electron microscopy (HRTEM) confirmed a typical orthorhombic V2O5 with the growth direction along [110]-direction of both nanostructures. Metallic Al, rather than Al3+-ion, was detected by X-ray photoelectron spectroscopy (XPS), affected the V2O5 crystallinity. The photoluminescence intensity of V2O5 nanostructure at 1.77 and 1.94 eV decreased with the increasing Al-dopant by about 61.6% and 59.9%, attributing to the metallic Al intercalated between the V2O5-layers and/or filled in the oxygen vacancies, which behaved as electron sinks. Thus the Al-doped V2O5 nanostructure shows the potential applications in smart windows and the electrodic material in a Li-ion battery.

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Integration of VO2 Thin Films on Si(100) for Thermal Switching Devices Applications

MRS Proceedings ◽

10.1557/proc-1174-v02-05 ◽

2009 ◽

Vol 1174 ◽

Cited By ~ 2

Author(s):

Alok Gupta ◽

Ravi Aggarwal ◽

Jagdish Narayan

Keyword(s):

Thin Films ◽

Resistivity Measurement ◽

Electrical Resistivity Measurement ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Close Proximity ◽

Potential Applications ◽

Gaussian Fit ◽

Vo2 Thin Films

AbstractThin films of vanadium dioxide (VO2) exhibit an interesting semiconductor to metal transition (SMT) when heated above ˜680C in which its resistivity changes by 3-4 orders of magnitude and its transmittance for IR wavelengths drops drastically. Integration of these thin films with Si (100) substrate is of immense technological importance due to its potential applications in sensor and memory based devices. Using pulsed laser deposition (PLD) we have demonstrated in this study that thin films of VO2 can be grown epitaxially on Si (100) substrate using an intermediate tetragonal Yttrium-Stabilized Zirconia (YSZ) layer without any further annealing. X-ray diffraction (XRD) and cross-section transmission electron microscopy studies were performed on the films and they are found to be of highly epitaxial nature. Electrical resistivity measurement were carried out using the four-point probe method and SMT parameters were extracted using Gaussian fit of the data. The S-M transition parameters are in close proximity with parameters obtained from vanadium oxide films deposited on oxide based substrates such as Al2O3 or TiO2.

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Investigation of the Effect of Uv-Assisted Oxidation and Nitridation of Hafnium Metal Films

MRS Proceedings ◽

10.1557/proc-780-y5.5 ◽

2003 ◽

Vol 780 ◽

Author(s):

C. Essary ◽

V. Craciun ◽

J. M. Howard ◽

R. K. Singh

Keyword(s):

Uv Radiation ◽

Photoelectron Spectroscopy ◽

Grazing Angle ◽

X Ray Diffraction ◽

Metal Thin Films ◽

X Ray ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Silicon Interface

AbstractHf metal thin films were deposited on Si substrates using a pulsed laser deposition technique in vacuum and in ammonia ambients. The films were then oxidized at 400 °C in 300 Torr of O2. Half the samples were oxidized in the presence of ultraviolet (UV) radiation from a Hg lamp array. X-ray photoelectron spectroscopy, atomic force microscopy, and grazing angle X-ray diffraction were used to compare the crystallinity, roughness, and composition of the films. It has been found that UV radiation causes roughening of the films and also promotes crystallization at lower temperatures.Furthermore, increased silicon oxidation at the interface was noted with the UVirradiated samples and was shown to be in the form of a mixed layer using angle-resolved X-ray photoelectron spectroscopy. Incorporation of nitrogen into the film reduces the oxidation of the silicon interface.

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α-Cellulose Fibers of Paper-Waste Origin Surface-Modified with Fe3O4 and Thiolated-Chitosan for Efficacious Immobilization of Laccase

Polymers ◽

10.3390/polym13040581 ◽

2021 ◽

Vol 13 (4) ◽

pp. 581

Author(s):

Gajanan S. Ghodake ◽

Surendra K. Shinde ◽

Ganesh D. Saratale ◽

Rijuta G. Saratale ◽

Min Kim ◽

...

Keyword(s):

Enzyme Immobilization ◽

Photoelectron Spectroscopy ◽

Cellulose Fibers ◽

Relative Activity ◽

Significant Activity ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Laccase Immobilization ◽

Surface Modified

The utilization of waste-paper-biomass for extraction of important α-cellulose biopolymer, and modification of extracted α-cellulose for application in enzyme immobilization can be extremely vital for green circular bio-economy. Thus, in this study, α-cellulose fibers were super-magnetized (Fe3O4), grafted with chitosan (CTNs), and thiol (-SH) modified for laccase immobilization. The developed material was characterized by high-resolution transmission electron microscopy (HR-TEM), HR-TEM energy dispersive X-ray spectroscopy (HR-TEM-EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) analyses. Laccase immobilized on α-Cellulose-Fe3O4-CTNs (α-Cellulose-Fe3O4-CTNs-Laccase) gave significant activity recovery (99.16%) and laccase loading potential (169.36 mg/g). The α-Cellulose-Fe3O4-CTNs-Laccase displayed excellent stabilities for temperature, pH, and storage time. The α-Cellulose-Fe3O4-CTNs-Laccase applied in repeated cycles shown remarkable consistency of activity retention for 10 cycles. After the 10th cycle, α-Cellulose-Fe3O4-CTNs possessed 80.65% relative activity. Furthermore, α-Cellulose-Fe3O4-CTNs-Laccase shown excellent degradation of pharmaceutical contaminant sulfamethoxazole (SMX). The SMX degradation by α-Cellulose-Fe3O4-CTNs-Laccase was found optimum at incubation time (20 h), pH (3), temperatures (30 °C), and shaking conditions (200 rpm). Finally, α-Cellulose-Fe3O4-CTNs-Laccase gave repeated degradation of SMX. Thus, this study presents a novel, waste-derived, highly capable, and super-magnetic nanocomposite for enzyme immobilization applications.

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Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽

10.3390/catal11030346 ◽

2021 ◽

Vol 11 (3) ◽

pp. 346

Author(s):

Sonam Goyal ◽

Maizatul Shima Shaharun ◽

Ganaga Suriya Jayabal ◽

Chong Fai Kait ◽

Bawadi Abdullah ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Catalyst Support ◽

Oxidation Potential ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Molar Ratios ◽

Optimum Parameters ◽

Reduction Of Co2 ◽

Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

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