D. K. Avasthi; S. K. Sarkar; A. Tripathi; T. Mukherjee
Abstract
The properties of materials at the nano scale critically depend on their size and shape, thus opening a new exciting area of nanotechnology. Its main thrust is to create novel functional materials with their unique physical, chemical and biological properties. The field of engineering of materials with ...
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The properties of materials at the nano scale critically depend on their size and shape, thus opening a new exciting area of nanotechnology. Its main thrust is to create novel functional materials with their unique physical, chemical and biological properties. The field of engineering of materials with desired properties is seeing a revolution as it becomes feasible to fabricate nanoscale building blocks having precisely controlled size and composition. Ionizing radiation (photon, electron and ion beams) have provided immense possibilities for engineering the desired properties of materials and are now emerging as indispensible tools for mesoscopic structuring [1-5]. The field of materials engineering through nano approach has demonstrated tremendous potential in the development of different types of novel materials with new characteristics and functions. The aim of nano engineering with photon, electron and ion beams is to control the nano scale structure of materials to optimize their properties and functionality.
Jai Prakash; A. Tripathi; G. B. V. S. Lakshmi; V. Rigato; Jalaj Tripathi; D. K. Avasthi
Abstract
Thin metal films of Ag (~10 nm) deposited on spin coated PVC film on quartz substrate, were irradiated with 150 keV Ar ions at fluences varying from 5×10 15 to 5×10 16 ions/cm 2 and characterized with Rutherford backscattering spectrometry (RBS), atomic force microscopy (AFM), scanning electron ...
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Thin metal films of Ag (~10 nm) deposited on spin coated PVC film on quartz substrate, were irradiated with 150 keV Ar ions at fluences varying from 5×10 15 to 5×10 16 ions/cm 2 and characterized with Rutherford backscattering spectrometry (RBS), atomic force microscopy (AFM), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) techniques. RBS spectra show sputtering of the Ag film. As a result of ion irradiation, isolated Ag nanoparticles are formed on the surface. The size and size distribution of Ag nanoparticles are found to be dependent on ion fluence. Contact angle measurements were carried out to study the hydrophilic nature of the surface at varying fluences. Results are explained in the framework of sputtering from the surface due to dense collision cascade resulting from Ar ion and Ag/PVC film interaction.
R. Singhal; A. Tripathi; D. K. Avasthi
Abstract
Electrically conducting carbon nanowires, all parallel to each other and embedded in fullerene C70 matrix are created by swift heavy ion irradiation of thin fullerene C70 film at low fluences (up to 10 10 ions/cm 2 ). The conductivity of the wires is several orders of magnitude higher than the surrounding ...
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Electrically conducting carbon nanowires, all parallel to each other and embedded in fullerene C70 matrix are created by swift heavy ion irradiation of thin fullerene C70 film at low fluences (up to 10 10 ions/cm 2 ). The conductivity of the wires is several orders of magnitude higher than the surrounding material and it is due to the transformation of fullerene into amorphous carbon within each ion hit zone. These conducting nanowires are evidenced by conducting atomic force microscopy. The typical diameter of the conducting tracks is observed to be about 11-21 nm.
Jai Prakash; A. Tripathi; J.C. Pivin; Jalaj Tripathi; A.K. Chawla; Ramesh Chandra; S.S. Kim; K. Asokan; D.K. Avasthi
Abstract
The present work envisages synthesis of magnetic nanocomposites by ion beam mixing technique using swift heavy ion irradiation of Ni-Teflon bilayer system and its magnetic characterizations. The nanocomposite is characterized by Rutherford backscattering spectrometry (RBS), transmission electron microscopy ...
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The present work envisages synthesis of magnetic nanocomposites by ion beam mixing technique using swift heavy ion irradiation of Ni-Teflon bilayer system and its magnetic characterizations. The nanocomposite is characterized by Rutherford backscattering spectrometry (RBS), transmission electron microscopy (TEM), scanning probe microscopy (SPM) and superconducting quantum interference device (SQUID) magnetometer. Cross-sectional TEM and magnetic force microscopy (MFM) results confirm the formation of nanocomposite. Magnetic characterizations reveal that nanocomposite exhibits ferromagnetic behavior with an increase in the coercivity, which is attributed to the formation of Ni nanoparticles. The coercivity of the nanocomposite is found to be 112 Oe at room temperature which is two orders of magnitude larger than that of the bulk Ni (0.87 Oe).
