Properties Of Nanocomposite Thin Films Research Articles

Photo-sensitive electrodes based on NiO: SnO2 Nano-composites prepared by chemical method

In the beginning, NiO/SnO2 nanocomposite thin film was prepared of nickel nitrate (1.5213) gm that was weighed and dissolved in distilled water to obtain a specific molar concentration at room temperature and prepared as nanoparticles and mixed with half mount (0.5121) gm of SnO2, in addition to other steps to obtain on the nanocomposite to study some features it. The structural properties of nanocomposite thin films using the chemical technique studied, such as XRD, FE-SEM, and AFM, were found that NiO/SnO2 Nano-composite crystallizes are hexagonal structures with an average crystallite size of 16.30nm. also, the FE-SEM images study the morphology of the NiO: SnO2 thin films, it catches sight of the nanostructure thin films of the NiO: SnO2 Clearly, the surface roughness of nanocomposite according to AFM noted that gets better as a result of the radical’s mobility. The FT-IR spectrum of the synthesized composite has been studied. UV-Spectral absorption of NiO: SnO2 where peak range of wavelength (225-550) nm and notice an increase in the absorption range towards the red wavelength after adding nickel oxide, and use the prepared sample in applied as photosensitive electrodes, voltage characteristics of chemical synthesized: SnO2 nanoparticles shows the current vs voltage plot of chemical-synthesized NiO: SnO2 nanoparticles coated onto glass substrates using dip coating method where add SnO2 due to increasing the conductivity of the nanocomposite.

Enhanced optical properties of recycled Fe2O3 reinforced in PVDF nanocomposite thin films for energy harvesting

Due to energy crises, development of renewable energy resources is currently in demand. Having superb physical and chemical properties, optical properties of nanocomposite thin films still need to be enhanced. In the current study, recycled Iron oxide (II) Fe2O3 obtained from rust is reinforced in Polyvinylidene Fluoride (PVDF) by solution casting method and analyzed by UV–visible and FTIR spectroscopy. Various parameters such as band gap, extinction coefficient, refractive index, and dielectric constant are calculated from absorption, and reflectance data. A significant decrease in direct and indirect band gap is noted. An increase in refractive index and improvement in the dielectric constant of nanocomposite thin films is observed. FTIR study confirms the enhancement in the β phase of the Fe2O3/PVDF nanocomposite thin films. Morphology of nanocomposite films is analyzed by using FESEM. Reinforced Fe2O3/PVDF nanocomposite thin films can be used for development of new generation pressure sensors and piezoelectric devices.

Optical and structural modifications of copper nanoparticles in a matrix of fullerene C60 under 220 keV Ag ion irradiation

Metal-matrix nanocomposites have a separate variety of objectives under provisions of their enhanced properties. Ion irradiation with low energy is a curious contrivance to achieve the bulk variations of distinct materials. The effect of low energy ion irradiation is explored on Cu-C60 nanocomposite thin films grown by the thermal co-deposition method. The Cu concentration in the as-deposited sample is found to be ∼ 45 at.% by Rutherford Backscattering Spectrometry (RBS). Owing to high metal concentration, a Surface Plasmon Resonance (SPR) peak is found at 616 nm in the as-deposited sample and the average size of Cu nanoparticles is determined to be ∼7.8 nm, with a broad size distribution. The as-deposited samples are irradiated with a beam of 220 keV Ag ions using an ion accelerator, which leads to moderate variations in the structural, electrical, and optical properties of nanocomposite thin film. The SPR peak is effectively red-shifted by ∼16 nm at a highest dose. The outcomes of Raman spectroscopy disclose the gradual transformation of fullerene C60 into amorphous carbon with increasing doses. High-Resolution Transmission Electron Microscopy (HRTEM) images demonstrate the minor growth of copper nanoparticles with ion irradiation. A growth in surface grains with ion dose is confirmed by Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscopy (AFM). The X-ray Photoelectron Spectroscopy (XPS) measurements have been used for the chemical state evaluation of the nanocomposite films. The I-V measurements show the conversion of fullerene into amorphous carbon with a loss in the resistivity of the film.

CuO/SnO2 Nanocomposite Thin Films: Effect of Solvent and Precursor on Optical and Structural Properties

New materials nanocomposites were synthesized for the degradation of organic and inorganic pollutants. This study reviews CuO/SnO2 nanocomposite thin films for their photocatalytic effect. The latter were deposited using the spray pyrolysis method, which is a simple, cheapest and rapid technique. Different concentration ratios of precursors and solvent are used. The thin films were deposited on ordinary glass substrates heated to 550∘C from solutions of copper chloride and tin chloride as precursors. The optical and structural properties of nanocomposite thin films have been demonstrated, and the equi-percentage of the precursor combination shows the good bandgap energy according to the literature. Investigations of structural properties using (SEM, EDS, XRD and RAMAN) techniques depict the good agreement photocatalytic degradation according to the surface roughness, quantities of elements and the existence of phases which will be of interest to the photocatalytic of organic and inorganic pollutants in aqueous and gas media according to the huge specific area due to the roughness and heterogeneity.

Tuning the optical and electrical properties of magnetron-sputtered Cu–ZnO thin films using low energy Ar ion irradiation

Cu doped ZnO (Cu–ZnO) nanocomposite thin films were successfully synthesized at room temperature by RF magnetron sputtering. The signature of Cu in pristine ZnO thin films was confirmed by Rutherford Backscattering Spectroscopy (RBS) with atomic concentration of ~10%. The Cu–ZnO thin films were irradiated with 800 keV Ar ion beam at three different ion fluences viz. 5 × 1015, 7 × 1015 and 9 × 1015 ions/cm2. As characterized by X-ray diffraction, the pristine and irradiated films show a hexagonal wurtzite structure with remarkable intensities of (100), (002) and (101) orientations. The surface morphology of the pristine and irradiated films was recorded using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The images clearly show the grain growth near the surface of films with increasing the ion fluences. The surface plasmon absorption (380 nm onwards) indicating the formation of metal nanoparticles in oxide matrices was confirmed by UV–visible spectroscopy of ion irradiated films. The electrical properties of the pristine and irradiated films were deduced by current voltage (I–V) and Hall measurements. The conductivity of the film increases as irradiation proceeds, achieves a maxima and then decreases with further processing of the ion beam. This study explores ion beam irradiation as a versatile tool to tailor the physical properties of nanocomposite thin films. Further, the properties can be precisely controlled by optimizing ion fluences and incident ion energy as well.

Magnetic property modulation of sputter-grown BiFeO3CoFe2O4 nanocomposite thin films

Abstract Self-assembled nanocomposite thin films in which ferromagnetic CoFe2O4 nanopillars grow in a ferroelectric BiFeO3 matrix have attracted tremendous interest for use as next-generation multiple state memory devices. To take advantage of the various magnetic properties of nanocomposites, it is necessary to control the strain state and shape of the CoFe2O4 pillars. Herein two methods are reported that can modulate the magnetic properties of nanocomposite thin films: changing the CoFe2O4 content in BiFeO3 and changing the aspect ratios of the CoFe2O4 pillars. The out-of-plane magnetic anisotropy of nanocomposites increased with decreasing CoFe2O4 ratio, and the anisotropy agreed with the value predicted from the strain effect. Nanocomposites with high-aspect-ratio CoFe2O4 pillars exhibited increased out-of-plane magnetic anisotropy as a result of their changing shape and increasing out-of-plane strain. Strain effects on the magnetic anisotropy of nanocomposites were confirmed by removing the BiFeO3 matrix via chemical etching.

Study on copper–fullerene nanocomposite irradiated by 120 MeV Au ions

We report the swift heavy ion irradiation induced tailoring of structural properties of nanocomposite thin films of copper nanoparticles embedded in fullerene matrix. Cu metal nanoparticles with low metal concentration (~ 5 at%) are deposited in fullerene C60 matrix. The thickness of the combined film is about 50 nm as revealed by Rutherford backscattering spectrometry. The absorbance of copper nanoparticles did not exhibit any characteristic plasmon resonance owing to low concentration of metal. The analysis of results of Raman spectroscopy demonstrated the structural transformation of fullerene to amorphous carbon at high fluence of 120 MeV Au ion beam. The formation of structures such as carbon nanowires as a result of irradiation has been revealed by FESEM micrographs. TEM results confirm the formation of small size copper nanoparticles in pristine film and growth of the Cu particles under the effect of swift heavy ions irradiation. I-V characteristics of metal-fullerene nanocomposite thin films give a clear indication that the value of resistance decreases due to effects of increasing fluence of ion irradiation.

Optical properties of Cu-C70 nanocomposite under low energy ion irradiation

Nanocomposite thin films consisting of Cu nanoparticles (NPs) embedded in fullerene C70 matrix are prepared by thermal co-deposition technique. Rutherford backscattering spectroscopy reveals that the thickness of thin film is about 35 nm and the atomic concentration on Cu metal is about 2%. The as-deposited thin films are irradiated with 120 keV N+ ions at various fluences ranging from 1 ×1014 ions cm−2 to 3 × 1016 ions cm−2. Low energy ion irradiation is proved to be an efficient technique to modify the optical, structural and electrical properties of nanocomposite thin films. Optical absorption spectra demonstrate that there was no signature of surface plasmon resonance (SPR) peak in the as-deposited film whereas a broad SPR band with the peak at ∼620 nm was observed for the film irradiated at the highest fluence (3 × 1016 ions cm−2). Raman spectroscopy is useful in providing information about the structural evolution of Cu-C70 nanocomposite thin films and confirms the gradual transformation of fullerene C70 into amorphous carbon with increasing fluence. Surface topography is probed by atomic force microscopy which shows the roughness of nanocomposite film varies with ion fluence.

Enhancement of dielectric properties of nanocomposite thin films prepared from polyimide and nickel doped barium titanate ceramic

Enhancement of dielectric properties of nanocomposite thin films prepared from polyimide and nickel doped barium titanate ceramic

Thermally induced tuning of SPR of metal-fullerene Ag(26%)-C70 nanocomposite

A bi-functional nanocomposite thin film containing Ag nanoparticles embedded in fullerene C70 is synthesized by thermal co-evaporation technique. Tuning of plasmonic resonance of Ag-C70 nanocomposite is obtained by annealing the nanocomposite thin film at different temperatures from 80 to 300°C for 30min. The optical and structural properties of nanocomposite thin film with respect to high temperature are studied by UV–visible absorption spectroscopy and X-ray diffraction. Transmission electron microscopy is performed to investigate the temperature dependent size evolution of Ag nanoparticles in fullerene C70 matrix. Growth of Ag nanoparticles is observed with increasing temperature above 200°C due to enhanced diffusion of Ag in fullerene C70 and Ostwald ripening. The optical and structural properties of metal-fullerene nanocomposite is not significantly affected upto a temperature of 150°C, after that a progressive blue shift of ~27nm in SPR wavelength is observed with increasing temperature. The tuning of SPR is ascribed to the thermal induced structural transformation of fullerene C70 matrix into amorphous carbon and also to mutual polarization of the particles.

Investigations on the Thermal Stability of Fullerene-Based (Ag-C70) Nanocomposite Thin Films

Fullerene-based bi-functional nanocomposite thin film (Ag nanoparticles embedded in fullerene C70 matrix) is synthesized by thermal co-deposition method. Thermal stability of Ag-C70 nanocomposite is investigated by annealing the nanocomposite thin film at different temperatures from 80 to 350 °C for 30 min. Optical and structural properties of nanocomposite thin film with respect to high temperature are studied by UV-visible spectroscopy and x-ray diffraction, respectively. Transmission electron microscopy is performed to observe the temperature-dependent size evolution of Ag nanoparticles in fullerene C70 matrix. A large growth of Ag nanoparticles is observed with temperature especially above 200 °C due to enhanced diffusion of Ag in fullerene C70 at higher temperature and Ostwald ripening. The properties of metal-fullerene nanocomposite is not significantly affected up to a temperature of 150 °C. With a further increase in temperature, a major blue shift of ~ 33 nm in SPR wavelength is seen at a temperature of 300 °C due to the thermal induced structural transformation of fullerene C70 matrix into amorphous carbon. A very large-sized Ag nanoparticle with a wide size distribution varying from 27.8 ± 0.6 to 330.0 ± 4.5 nm is seen at 350 °C and due to which, a red shift of ~ 16 nm is obtained at this temperature. This study throws light on the thermal stability of the devices based on metal-fullerene bi-functional nanocomposite.

Structural, optical and gas sensing properties of Ag-SnO2 plasmonic nanocomposite thin films

Nanocomposite thin films of Ag-SnO2 were synthesized by simple thermal evaporation based vapor deposition method combined with thermal annealing. The morphological, structural, optical and plasmonic properties of the nanocomposite thin films were studied by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and UV–visible absorption spectroscopy. UV–visible absorption studies revealed surface plasmon resonance (SPR) peak at 421nm confirming the presence of Ag nanoparticles in the nanocomposites. The annealed Ag-SnO2 nanocomposites exhibited enhanced CO gas sensing properties including high sensitivity, fast response-recovery and good selectivity towards CO gas. A tentative mechanism for the enhanced CO gas sensing properties of Ag-SnO2 nanocomposites is proposed.

Optical, structural and electrochromic behavior studies on nanocomposite thin film of aniline, o-toluidine and WO3

In the field of materials for electrochromic (EC) applications much attention was paid to the derivatives of aniline. We report on the optical, structural and electrochromic properties of electrochromic thin film based on composite of WO3 nanoparticles and copolymer of aniline and o-toluidine prepared by electrochemical polymerization method on fluorine doped tin oxide (FTO) coated glass. The thin film was studied by X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectroscopy. The morphology of prepared thin film was characterized by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and the thermal gravimetric analysis (TGA) as well. The optical spectra of nanocomposite thin film were characterized in the 200–900 nm wavelength range and EC properties of nanocomposite thin film were studied by cyclic voltammetry (CV). The calculation of optical band gaps of thin film exhibited that the thin film has directly allowed transition with the values of 2.63 eV on first region and 3.80 eV on second region. Dispersion parameters were calculated based on the single oscillator model. Finally, important parameters such as dispersion energy, oscillator energy and lattice dielectric constant were determined and compared with the data from other researchers. The nonlinear optical properties such as nonlinear optical susceptibility, nonlinear absorption coefficient and nonlinear refractive index were extracted. The obtained results of nanocomposite thin film can be useful for the optoelectronic applications.

Processing and Properties of Nanocomposite Thin Films for Micro-Solid Oxide Fuel Cell Applications

Microfabricated solid oxide fuel cells (micro-SOFCs) have recently gained attention as a promising technology, with the potential to offer a low temperature (as low as 300oC), reduced start-up time, and improved energy density for portable power applications. As a means for achieving the substantially reduced operating temperatures, new electrode materials with increased catalytic activity are being explored. At present, porous Pt is the most common cathode being investigated for micro-SOFCs. However, there are significant technical challenges for utilizing pure metallic electrodes at the operating temperatures of interest due to their tendency towards Ostwald ripening, as well as low bulk ionic conductivity. Nanocomposite materials (e.g. Pt/YSZ) are being studied as a promising alternative approach for providing both microstructural and electrochemical stability to the electrode layer. The microstructure and composition of the nanocomposite cathode material has been systematically investigated via controlled vacuum deposition conditions and resultant electrochemical properties measured by electrochemical impedance spectroscopy (EIS). Transmission electron microscopy (TEM) of the nanocomposite films reveals a percolating network of Pt and YSZ, along with interconnected nano-sized pores. An improvement in charge transfer kinetics associated with the oxygen reduction reaction has been demonstrated as compared to a pure porous Pt electrode, along with a significant improvement in microstructural stability during extended mSOFC operation. These results will be presented in detail.

Self-Consistent Approach to Calculation of the Optical Response and Absorption Profiles of Thin Nanocomposite Films

The absorption profiles for different nanocomposite thin films are calculated in the frame of approach based on a local-field method for calculations of optical properties of nanocomposite thin films having a matrix topology. The electrodynamic interactions between the inclusions as well as inclusions-matrix interactions are explicitly taken into account. It is shown that the absorption spectra are strongly dependent both on inclusions concentration and on materials the nanocomposite is made of. The dependences of the effective dielectric functions of different nanocomposites on type of inclusions, and their volume fraction are analyzed. The optical properties of thin nanocomposite films with different distributions of identical spherical inclusions along the film thickness are studied.

Transparent and Conductive Properties of Nanocomposite Thin Film of MWCNTs and PEDOT-PSS for Applications in OLED

Transparent and Conductive Properties of Nanocomposite Thin Film of MWCNTs and PEDOT-PSS for Applications in OLED

Electrical and Magnetic Properties of Multiferroic $(1\hbox{-}{\rm x})\ {\hbox{BiFeO}}_{3}\hbox{-}{\rm x}\ {\hbox{CoFe}}_{2}{\hbox{O}}_{4}$ Nanocomposite Thin Films Derived by Sol-gel Process

In the present work, multiferroic (1-x) BiFeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> -x (CoFe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ) ( x=0, 0.3, 0.5) nanocomposite thin films were prepared by sol-gel spin coating process. Structural, electrical and magnetic properties of nanocomposite thin films have been studied. X-ray diffraction study confirmed the co-existence of both perovskite BiFeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> (BFO) and spinel CoFe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> (CFO) phases. Atomic force microscopy shows CFO particles distributed in BFO matrix. These nanocomposite thin films exhibit both ferroelectric and ferromagnetic switching at room temperature. The magnetic and dielectric properties are improved by incorporation of CFO grains in matrix of BFO. The saturation magnetization (M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> ) increases as x varies from 0 to 0.5. For x=0.5, M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</sub> is found as high as ~ 196 emu/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . Coercivity is increased with CFO concentration and found maximum ( H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> ~ 1.20 kOe) for x=0.50. This large increase in coercivity indicates strong magnetoelastic coupling. The dielectric constant of the films is increased from 240 (for x=0) to 370 (for x=0.5). All composite films show ferroelectric behavior, however the ferroelectric properties are found to decrease with incorporation of magnetic phase.

Synthesis, morphology and optical properties of nanocomposite thin films based on polypyrrole-bromo-aluminium phthalocyanine

This paper is focused on the synthesis of nanocomposite Polypyrrole–Bromoaluminium phthalocyanine (PPy-BrAlPc). Morphology of prepared nano-compositethin films by electron beam evaporation technique have been well characterized by Field Emission-Scanning Electron Microscopy (FESEM). FESEM shows that the grain sizes are increased with increase in concentration of pyrrole. The optical properties of nanocomposite thin films have been investigated using a spectrophotometric measurement of absorbance in the wavelength range 300–800 nm. Absorption spectra of the films show B-band in the UV region followed by Q-band in the visible region. Moreover, the optical band gaps of the thin films are evaluated. It is found that the energy of the optical band gap increases as the concentration of Bromo-aluminium phthalocyanine increases.

Structural, mechanical and biological comparison of TiC and TiCN nanocomposites films

Abstract The vacuum deposition provides great flexibility for manipulating material's chemistry and structure. A combination of metallic (Ti) and carbon phase can enhance certain physical properties of nanocomposite thin films. In this work, the comparison of nanocomposite films composed of TiC or TiCN grains embedded in amorphous carbon matrix is reported. The films were prepared by dc magnetron sputtering at 200 °C in argon and nitrogen. In the case of argon deposition, 4–5 nm TiC grains in carbon matrix were observed. The nitrogen deposition combined with low content of Ti (∼1.2 at%) proved to be insufficient for the development of larger crystals. The carbon had carbide character in TiC film, whereas in TiCN film all the carbon had graphite type environment. TiC film deposited in argon exhibited better mechanical properties than TiCN films deposited in nitrogen. In both cases, the good biocompatibility was observed after 7 days osteoblast cells seeding.

Optical properties of solution grown PVDF-ZnO nanocomposite thin films

The optical properties have been investigated using EDX, UV–Visible spectroscopy and Raman spectroscopy. The nanocomposite formation was confirmed using EDX as well as UV-Visible absorption spectroscopy. Raman study confirms the β phase of PVDF. The UV–Vis spectroscopy accounts for a significant continuous decline in optical band gap and optical activation energy, while increase in refractive index with ZnO nanoparticles incorporation. The results imply that the effectiveness in shielding of UV radiation is due to absorption capacity of ZnO nanoparticles incorporated in PVDF. The increase of absorption in the UV-region of the spectrum is due to the excitations of donor level electrons to the conduction band at these energies. This decrease of band gap may be attributed by presence of unstructured bulk defects. The optical properties of nanocomposite thin films were shown to depend on ZnO content and possessed the most optimal optical properties.