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Synthesis of calcium hydroxide nanoparticles was done by chemical precipitation in aqueous medium at room temperature. Aqueous solution of calcium nitrate tetrahydrate (Ca(NO3)2·4H2O) and sodium hydroxide are used as precursor. The effect of rate of mixing of sodium hydroxide in calcium nitrate tetrahydrate was studied during the synthesis of calcium hydroxide. The prepared Ca(OH)2 powder was characterized by using UV–Vis spectroscopy, TGA and DTA, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM) and energy dispersive X-ray analysis (EDX). From the UV–Vis characterization, an increase in band gap from 4.3 eV to 5.8 eV with increase in mixing rate of sodium hydroxide in calcium nitrate tetrahydrate from 1 ml/min. to 5 ml/min was found respectively. The weight loss in TGA was also found to increase with increase in mixing rate. The change in weight loss and band gap with mixing rate was discussed in terms of growths during synthesis of calcium hydroxide.

C60/Ag/Au multilayer thin films are synthesized on glass substrate by thermal co-deposition method followed by ion irradiation by high energy ion beam of 120 MeV Au ions using Pelletron accelerator. The effect of ion irradiation by 120 MeV Au ions on the optical and structural properties of the synthesized multilayer thin film samples at different fluences ranging from 6 × 1012 to 3 × 1013 ion/cm2 is investigated. By UV–visible spectroscopy, optical studies of pristine and Au ion irradiated samples are examined. Surface Plasmon Resonance (SPR) peaks of Au and Ag nanoparticles are obtained at wavelength ∼687 nm and ∼628 nm, respectively after irradiation at a fluence of 3 × 1013 ions/cm2. Atomic force microscopy was performed to analyze the surface morphology after irradiation. Due to ion irradiation, overall roughness estimated to be increased with increasing fluence. TEM revealed the growth of metal nanoparticles in size due to agglomeration after irradiation. I–V measurements are preformed to study the electrical properties after irradiation with 120 MeV Au ion.

Metal-matrix nanocomposite has a multitude of applications. The local structure and optical modifications of these materials are studied using fullerene as a matrix material, incorporated by noble metal nanoparticles of Cu. These metal-fullerene nanocomposites are useful because of the amalgamation of different properties of the fullerene and metal nanoparticles. Cu being cheap and abundant in nature has an advantage over other metal nanoparticles. Cu nanoparticles being more reactive are stabilized by incorporating them in fullerene matrix and therefore can be used in various applications. The structural and optical properties (mainly SPR) of Cu-fullerene nanocomposites are tuned by different methods and synthesis procedures such as (a) Ion irradiation, (b) ion implantation, (c) thermal annealing and (d) increasing the concentration of the Cu nanoparticles in the matrix material. In this review all the factors influencing the tuning of structural and optical properties of Cu-fullerene nanocomposites are investigated in detail. Each property is studied by different characterization techniques such as, TEM, UV–visible spectroscopy and electron diffraction method.

The effect of 220 keV Ag ion beam irradiation on the optical and structural properties of thermally co-deposited Au-C60 nanocomposite thin films on a quartz substrate is investigated by irradiating samples at different doses. To determine the exact gold (Au) concentration in the film and thickness of the film, Rutherford Backscattering Spectrometry (RBS) was utilized on the as-deposited film. The Surface Plasmon Resonance (SPR) of Au nanoparticles embedded into the fullerene C60 matrix was seen at 721 nm in the as-deposited sample. A ∼34 nm redshift in SPR wavelength was obtained at a dose of 1 × 1014 ions/cm2 which was mainly due to the increase in the size of Au nanoparticles with irradiation. At higher doses, a blue shift of ~67 nm was obtained at a dose of 1 × 1016 ions/cm2 which was due to the transformation of fullerene C60 matrix into amorphous carbon with a much lower dielectric constant at higher doses. The progressive transformation of fullerene C60 into amorphous carbon with increasing doses was confirmed by Raman spectroscopy. The size of Au nanoparticles in the highest dose irradiated sample was found to be ∼3.9 nm by High-Resolution Transmission Electron Microscopy (HRTEM) bright-field measurements. The size modifications of nanoparticles and SPR wavelength tuning of these nanoparticles are very much needed to use them in organic solar cell.

Here we report synthesis and characterization of chemically synthesized calcium hydroxide (Ca(OH)2) with and without deliberate presence of NaNO3 as an impurity. Calcium nitrate tetrahydrate (Ca(NO3)2.4H2O) is used as precursor and alkaline NaOH solution is used as precipitant to synthesize the Ca(OH)2 samples. The samples were characterized by XRD, FESEM, FTIR spectroscopy, DTA, TGA and UV-Vis spectroscopy techniques. From the UV-Vis spectroscopy results, it is found that the Ca(OH)2 with NaNO3 impurity has higher bandgap than the sample without NaNO3. The weight loss in TGA is also more for the Ca(OH)2 with impurity than the one for without impurity. The results are discussed in terms of composition formed during synthesis process.

Au-Fullerene nanocomposite thin films synthesized by thermal co-evaporation method are irradiated by low energy (2.6 MeV) Ar ions at fluence ranging from 1 × 1014 ions-cm−2 to 3 × 1016 ions-cm−2. To avoid the retrogression of attributes of fullerene subjected to presence of Au, selected concentration and thickness of gold film is kept very small. UV–visible spectroscopy demonstrates the surface plasmon resonance (SPR) peak at 677 nm for the pristine film and at 590 nm after irradiation at fluence of 1 × 1014 ions-cm−2, displaying a shift of 87 nm towards lower side. This confirms that the refractive index of fullerene decreases as an influence of exposure to Ar beam irradiation. Shift in refractive index is explained on the basis of Mie theory which is established by the existence of D and G band after irradiation as displayed in the results of Raman Spectroscopy. A slight increase in the size of Au nanoparticles in irradiated films is observed which is illustrated by TEM images. Atomic Force Microscopy (AFM) images indicate the varying roughness of thin films after irradiation and morphology is determined by SEM images. I-V characterization shows the conductive behavior of Au-fullerene nanocomposite film before and after irradiation at different fluence. There are two phenomena occurring simultaneously with the increase in ion irradiation fluence; one is increase in the size of metal nanoparticle and another is transformation of fullerene in amorphous carbon. This leads to the change in the SPR position of metal fullerene nanocomposite thin film, making ion irradiation as an effective tool to enhance and optimize the optical properties of metal fullerene nanocomposite thin film.

Summary A sandwiched structure with a metal layer embedded between two metal oxide layers was fabricated on glass substrate to be used as transparent electrode in organic devices. The oxide layers of ZnO were dip coated with a thickness of about 60 nm each while the metal inter layer was sputter coated with a thickness of about 5 nm at room temperature. The deposited films were annealed at 200°C for 2 hrs to remove all additives. Such structures have been found to be suitable for applications in organic solar cell and OLED. The samples have been characterized using XRD, SEM and EDAX. Optical properties were measured by UV-VIS and AFM was used to measure the roughness. The XRD pattern indicates the nearly amorphous structure of the thin film. The size of the aggregates as given by FESEM ranges from 30–50 nm and EDAX confirms the presence of elements of the three layers. The roughness as calculated using AFM is about 2.40 nm. UV-VIS spectroscopy showed a high transparency of over 87% in the visible region for the sandwich structure making it suitable for TCO applications.