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In present research work, La+3 substitution in barium hexaferrite having formula BaLaxFe12−xO19 where x varies from 0.1 to 0.6 with the step size of 0.1 have been prepared using traditional solid-state method and sintered at 1100 °C for 2 h. The impact of La+3 ions on structural, morphological, optical, magnetic and ferroelectric properties of the samples have been investigated using X-ray diffractometer, Fourier transform infrared spectroscopy, scanning electron microscope, UV–Vis spectroscopy, Vibrating Sample Magnetometer and ferroelectric technique, respectively. The structural analysis revealed the formation of single-phase hexagonal structure. The surface morphology shows that the grains have definite boundary with some agglomeration. The value of band energy decreases as the concentration of La+3 ions increase in barium hexaferrite. The VSM data endorse the clear ferromagnetic M–H curve in which the value of coercivity and saturation magnetization have non-monotonic sequence. Ferroelectric analysis reveals that all samples except sample x = 0.1 have less polarizability which leads to these materials to be used in high-frequency applications.

Co-existence of ferroelectric and ferromagnetic nature in bismuth substituted M-type barium hexaferrites has been investigated in this current project. A series of samples with formula BaBixFe(12-x) (where x varies from 0.2 to 1.2 with step size of 0.2) have been prepared by conventional powder metallurgy route. The structural, functional group analysis, surface morphology, optical, dielectric, ferroelectric, and ferromagnetic properties of samples are characterized using X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), UV-visible spectroscopy (UV-Vis), LCR meter, ZT-IA, and vibrating sample magnetometer (VSM) respectively. XRD and FTIR confirm the single phase of hexagonal structure of bismuth doped M-type barium hexaferrite. The platelet like structures is observed on the surface of the samples. The optical band gap energy decreases due to the formation of intermediate states between the valence and conduction bands as the concentration of Bi ions increases. The variation in dielectric constant and ac conductivity depends upon the frequency of the applied field as well as the composition of the samples. P-E loop shows clear ferroelectric behavior. The maximum saturation polarization of 5.42 μC/cm2 is observed. The presence of FeO6 octahedron at three (12 k, 2a, and 4f2) crystallographic sites in the hexagonal unit cell is the origin of induced polarization. Magnetic properties reveal the strong ferromagnetism of bismuth doped M-type barium hexaferrite at room temperature.

A series of CdxCo1-xCr0.5Fe1.5O4 ferrite sample with (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) have been prepared by powder metallurgy method. The structural, morphological, magnetic and optical properties of prepared samples have been characterized by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), Vibrating sample magnetometer (VSM) and UV–visible spectroscopy respectively. The distribution of cation in site-A, site-B and lattice parameters have been deduced by X-ray-diffraction-data analysis. The lattice constant (A°) was found to increase with increment of Cd2+ contents in the spinel ferrites. The hysteresis curves undoubtedly designate the soft nature of the prepared ferrite samples. The saturation magnetization (Ms) decreases with increasing Cd contents3w, this result is interrelated to the magnetic moments of Cd2+ ions. The Y–K angles decrease with addition of cadmium content and this decrement in the Y–K angles proposes the lessening of triangular spin arrangements on octahedral sites which consequently lead to decrease the A-B interaction. The band gap energy is showing the increasing trend which is due to decreasing crystallite size.

The evolution of various properties of cobalt-doped M-type barium hexa-ferrites has been investigated in this project. A series of cobalt-doped M-type barium hexa-ferrites having general composition BaCoxFe(12-x)O19 with x = 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 was prepared using powder metallurgy route. For the thermal decomposition, prepared powders were heat-treated at 1373 Ko for 2 h in a muffle furnace. The structural analysis, 3-D structural visualization, functional group analysis, surface morphology, elemental analysis, optical, dielectric, ferromagnetic, and ferroelectric properties of samples were characterized using different characterization techniques. X-ray diffractometer and Fourier transform infrared spectroscopy confirmed the formation of single-phase hexagonal structure of cobalt-doped M-type barium hexa-ferrite. The optical bandgap energy and saturation magnetization of the prepared samples increased with increasing cobalt concentration which made them suitable for light-emitting diodes and laser formation. Their dielectric properties show the insulting nature of the ferrites. Ferro-electric loop exhibits formation of non-centrosymmetric covalent bonds with an increase in the electric coercive field and remanent polarization. The electric polarization in the unit cell of barium hexa-ferrites is based on FeO6 octahedron. The oxygen O6 is located at three crystallographic sites (4f, 2a and 12 k). The iron ion is normally located at the center of the oxygen octahedron. The formation of non-centrosymmetric covalent bonds is due to the shifts off-center of iron ions under the application of external field. The ferroelectric loops are also not properly closed which indicates the magnetoelectric (ME) coupling and improves multiferroicity of the material.

This research focused on the mechanical electrical and biological properties of magnesium doped (Mgx, x = 0.5 - 2.5 mol%) hydroxyapatite(Hap) using chemical method. It was observed that addition of magnesium produced the secondary phase (whitlockite) depended on the concentration of magnesium using the XRD, FTIR and Raman techniques. These two phases forming BCP(Biphasic) are beneficial from the implant point of view. The dielectric properties were measured as a function of frequency for different concentration of Mg. For 1.0 -2.0mol% doped Mg samples showed dielectric constant value within the range required for implant material. The bioactivity and However, beyond 2mol% of Mg third phase of magnesium oxide was also observed which enhanced the micro-hardness and bioactivity of specimen.

A series of Agx-substituted Co0.05−x Zn0.95O (x = 0.00–0.05) nanoparticles calcined at 700 °C have been synthesized using a simple co-precipitation technique. The prepared nanoparticles have been analyzed for their structural, optical, magnetic, and dielectric properties using X-ray diffractometer, Fourier infrared spectroscopy, UV–visible spectroscopy, vibrating sample magnetometer, and inductor capacitor and resistor meter, respectively. The XRD results verify the formation of pure hexagonal wurtzite structure. FTIR spectra show a band at 439 cm−1 that is the characteristic stretching band of Zn–O which also confirms the formation of hexagonal structure. The band-gap energy decreases as the concentration of Ag increases except for samples with concentration x = 0.01 and x = 0.03. VSM results reveal that nanoparticles exhibit ferromagnetism at room temperature. The dielectric constant and tangent loss decreases with increasing frequency. However, the a.c. conductivity increases with increasing frequency. The prepared nanoparticles can be used in a variety of applications such as optoelectronic, memory, and microelectronic devices.

In this research project a series of chromium substituted barium hexa-ferrites with formula BaCrxFe(12-x)O19 (x = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6) have been synthesized using powder metallurgy route, sintered at 1100 °C for 2 h. The structural, functional analysis, surface morphology, magnetic and ferroelectric properties have been investigated using X-ray diffractometer, Fourier infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer, and ferroelectric technique, respectively. The structural analysis reveals the formation of barium hexaferrite structure with minor secondary phase of Hematite α- Fe2O3 in first five samples. Surface morphology shows that all grains have definite grains shape and grain boundaries. VSM analysis revealed the antiferromagnetic loops due to existence of hematite phase in (x = 0 to x = 0.5) samples, whereas the sample (x = 0.6) shows the ferro-magnetic behavior. Ferroelectric measurement shows centrosymmetric and non-centrosymmetric orientation and maximum remnant polarization due to presence of more Fe2+ ions in (x = 0.1–0.5) so that not proper closing of first five samples enhanced the magnetoelectric (ME) coupling.

In this present work, antimony-substituted cadmium ferrites with formula CdSbxFe2−xO4 (x = 0.1, 0.2, 0.3, 0.4, 0.5) have been synthesized using the ceramic route. The structural, surface morphological, magnetic and optical properties have been investigated using X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, vibrating sample magnetometer and UV–visible spectroscopy, respectively. XRD confirms the single cubic spinel structure of antimony-substituted cadmium ferrites. The lattice parameter increases due to the replacement of Fe+3 (0.64 A) ions with Sb+3 (0.76 A). FTIR gives the main vibrational band that lies in the range of 400–600 cm−1 which might be due to the stretching vibration of oxygen and metal ions, confirming the formation of spinel ferrite. The saturation magnetization decreases and coercivity increases as the concentration of non-magnetic antimony ion increases. The optical band gap energy decreases with increasing the concentration of antimony ions.

A series of soft ferrites with the general formula MgCrxFe2−xO4, where x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5, have been fabricated using the powder metallurgy route. The comprehensive study of Cr-doped magnesium ferrite has been carried out employing different techniques. The structural, surface, elemental, magnetic and dielectric properties have been examined using x-ray diffractometry, Fourier infrared spectroscopy, scanning electron microscopy, a vibrating sample magnetometer and an inductor capacitor resistor meter, respectively. The formation of a single-phase cubic spinel structure is confirmed by x-ray diffractometry and Fourier transform infrared spectroscopy. It is revealed that the lattice constant decreases with increasing Cr content. The surface of these samples consists of nano-particles in the range of 90–175 nm, while energy dispersive x-ray spectroscopy has been subject to elemental analysis of all the samples. The saturation magnetization and remanence has a nonlinear trend with increasing Cr content, while the coercivity decreases monotonically. The dielectric properties also confirm the formation of spinel ferrites.

The simple and cost-effective powder metallurgy method has been employed to prepare a series of copper substituted cobalt chromium ferrites CuxCo1-xCr0.5Fe2O4 (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0). The calcination of the samples has been carried out at 1100 °C for 24 h. X-Ray Diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR) measurement proves the formation of cubic spinel ferrites. Vibrating Sample Magnetometer (VSM)) analysis revealed that the substitution of copper in the Co-Cr ferrites leads to reduce the magnetic moment that in turns decrease the saturation magnetization and coercivity. The Ultra violet visible spectroscopy (UV–VIS) showed that the band gap energy increases with copper substitution which is due to reduction in crystallite size. The results indicate that the replacement of copper with the cobalt-chromium ferries strongly influences the crystal structure, microstructure, magnetic parameters and band gap energy.

A series of Ti 0.9 Fe 0.1-x Ni x O 2 (x = 0.0, 0.02, 0.04, 0.06, 0.08, 0.1) has been synthesized through the solid state reaction method at annealing temperature of 1100 °C for two hours. The synthesized samples have been analyzed by X-Ray diffractometer (XRD), Raman spectroscopy, Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Vibrating sample magnetometer (VSM) and ultraviolet visible (UV–VIS) spectroscopy for structural investigations, defects measurements, surface morphology, magnetic and optical properties respectively. Structural analysis has revealed the dominant structure of rutile. An intensity loss and peak broadening of TiO 2 (rutile) vibration lines have been observed from Raman analysis, which is an indication of presence of oxygen vacancies. Magnetic analysis has revealed ferromagnetic behavior at room temperature. Optical characterization has shown the blue shift in band gap energy with increase of Ni concentration.

A series of copper substituted cobalt chromium ferrites, CuxCo1-xCr0.5Fe1.5O4(x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) has been synthesized, by employing powder metallurgy method. Calcination of the samples has been carried out for 24 hours at 1100 °C. The resultant materials have been investigated by using a variety of techniques, including X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM)), scanning electron microscopy (SEM), and ultraviolet visible spectroscopy (UV-Vis). The XRD patterns confirmed that all compositions had a cubic spinel structure with a single phase and the lattice parameter was found to increase with increasing copper concentration. FT-IR spectroscopy has been used for studying the chemical bonds in the spinel ferrite. Shifting of the bands ν1and ν2has been observed. It has been revealed from VSM analysis that saturation magnetization and coercivity decrease with rising the Cu+2doping. Magnetic properties have been explained on the basis of cation distribution. Scanning electron microscopy (SEM) has been used to study the surface morphology of prepared samples. UV-Vis analysis revealed the optical absorption of the samples. An increase in band gaps has been observed with increasing copper concentration in the sample.

Thin films of Zn0.9 Co0.1−xNixO (x = 0.0, 0.02, 0.04, 0.06, 0.08, 0.1) series were deposited by Pulsed Laser deposition technique (PLD) on a single crystal (100) silicon substrate. The structure of the films was confirmed as single phase hexagonal wurtzite structure by X-ray diffraction technique (XRD). The highest intensity peak was found at (002) plane. The surface morphology of thin films studied by Scanning Electron Microscope (SEM) depicted the high grain growth with definite boundaries. The room temperature resistivity measurements were carried out by four-point Probe methods which showed the semiconducting behavior of the thin films. Magnetic properties characterized by Vibrating Sample Magnetometer (VSM) at room temperature, exhibited the weak ferromagnetic or superparamagnetic behavior due to the alignment of the spins in the same direction around the oxygen vacancy and Co/Ni ions. Optical properties were observed by Spectroscopic Ellipsometry. The thickness of the films lied in 200–265 nm range and the bandgap energy was found to decrease from 3.09 to 3.03 eV confirming the inclusion of Ni a deep level impurity.

This paper is dedicated to deposit zinc substituted cobalt ferrite (Co0.8Zn0.2Fe2O4) thin films on glass substrate using electron beam deposition technique. The effect of post annealing temperature on structural, magnetic, and optical properties of thin films has been investigated. Thin films have been characterized using x-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM), vibrating sample magnetometer (VSM), UV-VIS spectroscopy, and spectroscopic ellipsometry (SE) analysis. The as-deposited thin films are amorphous in nature. After deposition, these thin films post annealed at different temperature ranges from 200 to 500 ∘C to enhance the crystallinity of films. The film post annealed at 200 ∘C is also amorphous in nature. As the post annealing temperature increases, the thin films become more crystalline. X-ray diffractometer and Raman analysis confirm the formation of cubical inverse spinel structure of thin films. The saturation magnetization of the thin films decreases with the annealing temperature due to the sites occupancy of cations between tetrahedral and octahedral. The reduction in coercivity is correlated with the anisotropy constant, but the anisotropy value is still high which is suitable to form stable magnetic storage memories. The band gap energy are decreased which is mainly attributed due to increase in grain size of the film. It is noted that the band gap energy of these thin films are higher than that of bulk material, so these may be suggested for use in wide band gap applications.

A series of six samples with a general formula Ti0.9Fe0.1−xCoxO2 (x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.1) has been synthesized by solid-state reaction method at annealing temperature of 1150 ∘C for 2 hours. The synthesized samples have been characterized by X-ray diffractometer, Raman spectroscopy, scanning electron microscopy, EDX, vibrating sample magnetometer, and ultraviolet-visible spectroscopy to investigate structural, defective, morphological, elemental, magnetic, and optical properties. Structural analysis revealed dominant structure of rutile with a minor peak of hematite and anatase. An intensity loss and peak broadening of TiO2 (rutile) vibration lines has been observed from Raman analysis. Magnetic characterization showed ferromagnetic behavior at room temperature. Optical characterization revealed blue shift in band gap energy with increasing amount of Co concentration.

In this research work a series of Ti0.9Fe0.1-xNixO2 thin films with Ni concentration varying from x=0 to 0.1 have been grown onto single crystal Si (100) substrate by pulsed laser deposition. The two ferromagnetic impurities Fe and Ni were co-doped in TiO2 films simultaneously in order to enhance their optical, magnetic and electrical properties. The targets for the deposition of thin films have been prepared via solid state reaction route. The thin film samples were annealed in air at 800°C for two hours in order to control their phase stability, carrier concentration and magnetic properties. Their structural properties were studied by X-ray diffractometer, which revealed rutile phase of TiO2. The film surface morphology, observed by scanning electron microscopy, was porous and smooth with the structure of rutile phase. The magnetic properties were investigated by vibrating sample magnetometry at room temperature and showed a ferromagnetic behavior for all the thin films. The optical properties, investigated by spectroscopic ellipsometry revealed a red shift in band gap energy as a function of Ni contents. Electrical characterization has been done by four probe Hall effect measurements at room temperature. The N-type semiconducting behavior has been observed at x=0, 0.02, 0.04 and 0.06 and p-type behavior for x=0.08 and 0.1. P-type conductivity is required for use in spintronics devices.

Laser induced breakdown spectroscopy of ZrO2 plasma in the presence and absence of magnetic field has been investigated. The plasma was generated by employing Nd: YAG laser (1064 nm, 10 ns) at various fluences ranging from 6.4 J cm−2 to 25.6 J cm−2 under argon environment of pressure of 100 Torr. Both emission intensity and electron temperature show increasing trend with increasing the fluence, whereas, electron number density of ZrO2 plasma decreases with increasing the laser fluence. It is revealed that values of emission intensity, electron temperature and electron number density of ZrO2 plasma are slightly higher in the presence of magnetic field as compared to field free case at all fluences. This increase in plasma parameters is attributed to magnetic confinement and Joule heating effect. With the variation of fluence the electron temperature of ZrO2 plasma varies slightly from 5345 K to 5475 K in the absence of magnetic field, whereas in case of magnetic field this value enhances from 5435 K to 5600 K. Similarly the electron number density of ZrO2 plasma varies from 1.80 × 1018 cm−3 to 3.50 × 1018 cm−3 in the absence of magnetic field, whereas in case of magnetic field, the variation in electron number density varies from 1.75 × 1018 cm−3 to 4.25 × 1018 cm−3. The existence of magnetic confinement effects is confirmed by the analytical evaluation of plasma parameter β, which is smaller than 1 under all experimental conditions. It is also revealed that both the laser fluence as well as magnetic field significantly influence the ZrO2 plasma parameters.

This paper reports the fabrication and characterization of silicate glass-ceramics doped with (0-12mol%) CaF2. TGA-DSC analysis was carried out to determine the crystallization temperature and stability of glass measured by two glass parameters; Hruby parameter KH=(Tx-Tg)/(TL-Tx) and Weinberg parameter KW=(Tc-Tg)/TL. It was found that with CaF2 doping improved sinterability at low temperature and provided stability to the glass. The XRD pattern exhibits a single phase of combeite and doping of CaF2 cause increase in crystallite size. Microstructure of samples was also improved with CaF2 addition, pores were significantly reduced. After 15days immersion in simulated body fluid all samples developed apatite layer onto its surface. Hence, the addition of CaF2 provided bioactive glass-ceramic material having a low processing temperature.

This paper is dedicated to investigate the effect of Co 2+ ions in magnetite Fe 3 O 4 nano-particles with stoichiometric formula Co x Fe 3-x O 4 where (x = 0, 0.05, 0.1 and 0.15) prepared by co-precipitation method. The structural, thermal, morphological, magnetic and optical properties of magnetite and Co 2+ doped magnetite nanoparticles have been carried out using X-ray Diffractometer, Fourier Transform Infrared Spectroscopy, Themogravimetric Analysis, Scanning Electron Microscopy, Vibrating Sample Magnetometer (VSM) and UV–Vis Spectrometer (UV–Vis) respectively. Structural analysis verified the formation of single phase inverse spinel cubic structure with decrease in lattice parameters due to increase in cobalt content. FTIR analysis confirms the single phase of Co x Fe 3-x O 4 nanoparticles with the major band at 887 cm −1 , which might be due to the stretching vibrations of metal-oxide bond. The DSC results corroborate the finding of an increase in the maghemite to hematite phase transition temperature with increase in Co 2+ content. The decrease in enthalpy with increase in Co 2+ concentration attributed to the fact that the degree of conversion from maghemite to hematite decrease which shows that the stability increases with increasing Co 2+ content in B-site of Fe 3 O 4 structure. SEM analysis demonstrated the formation of spherical shaped nanoparticles with least agglomeration. The magnetic measurements enlighten that the coercivity and anisotropy of Co x Fe 3-x O 4 nanoparticles are significantly increased. From UV–Vis analysis it is revealed that band gap energy increases with decreasing particle size. This result has a great interest for magnetic fluid hyperthermia application (MPH).

This current project is dedicated to a fast, easy and one step method for the synthesis of gold nano-particles. Gold (Au) nano-particles have been fabricated by laser ablation method in de-ionized water. The purpose was to explore the dependence of the various properties of the gold nano particles on the nature of laser. In order to prepare colloidal solutions, a low power continuous wave (CW) diode laser and a nanosecond pulsed Nd:YAG laser have been used to ablate the gold target. The structural, physical, optical and thermal characteristics of prepared nano-particles have been investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), UV–vis spectroscopy and thermal conductivity of liquids and gases unit (TCLGU), respectively. The XRD analyses revealed the formation of polycrystalline gold nano-particles with (111), (200) and (220) plans in case of both the lasers. AFM micrographs showed that prepared nano-particles are spherical in dimensions. The size of nanoparticles synthesized by CW laser ranges from 5 to 20 nm whereas the size ranges from 12 to 49 nm in case of pulsed laser. UV–vis spectroscopy showed surface plasmon resonance (SPR) peak at 512 nm for CW laser prepared nanoparticles as compared to pulsed laser at 525 nm which is also indicative of the smaller size in case of CW laser. The thermal conductivity of colloidal solution prepared by CW laser is 33% whereas in case of pulsed laser is 48% more as compared to the deionized water (base liquid).

The current work is dedicated to investigate the effect of nickel and cobalt doping on the crystallanity, stability, and magnetic and optical properties of magnetite (Fe3O4) nano-particles. Nickel- and cobalt-doped magnetite (Ni x Fe3−x O4 and Co x Fe3−x O4 with x = 0, 0.05, 0.1, and 0.15) nano-particles have been prepared by chemical co-precipitation method and are characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), themogravimetric analysis (DSC-TGA), scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), and UV-visible spectroscopy to study their structural, thermal, morphological, magnetic, and optical properties, respectively. The structural analysis indicates the formation of a single-phase cubic inverse spinel structure with a decrease in lattice parameters with increasing Ni and Co concentrations. Thermal analysis reveals that the transition temperature increases. The increase in transition temperature is due to the maghemite to hematite phase transition after the replacement of Fe2+ with Co2+ or Ni2+ in the B-site. The increase in transition temperature is attributed to the fact that stability increases with increasing cobalt content. Morphological analysis indicates the spherical shape of nano-particles with least agglomeration at all concentrations. The optical band gap energy increases as the particle size decreases. Magnetic properties reveal that the saturation magnetization decreases in both cases, but coercivity increases in the case of Co. This behavior is ascribed due to the high anisotropic cobalt cation doping in magnetite (Fe3O4) nano-particles, which is the goal to achieve the increase in hyperthermic efficiency.

The series of M-type Ba1-xSrxFe12O19 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1) have been fabricated using powder metallurgy route. The effects of strontium ions have been systematically investigated. The samples are sintered at 1200 °C for 2 h. The structural properties and surface morphology is determined using X-ray diffraction technique, Fourier Infrared Spectroscopy and Field Emission Scanning Electron Microscope respectively. The magnetic and optical properties are carried out using vibrating sample magnetometer and UV–vis spectroscopy. The XRD analysis revealed that these samples have hexagonal structure. FTIR analysis confirmed that bands in the range 430–590 cm−1 are due to the stretching vibration of oxygen atom and metal ions (M-O) that is Fe-O confirming the formation of hexa-ferrite. The average grain size is determined using FSEM i.e about 0.37–1.5 μm. The VSM analysis showed that saturation magnetization decreased with increasing concentration of Sr+2 ions and this decrease is due to the different site occupation of Sr+2 and Fe+3 ions. The band gap energy decreased with the increasing concentration of strontium ions. This is due to the vacancies of electrons in the valance band of Ba and Sr. The decrease in the distance between conduction and valance band causes the increase in conductivity due to which band gap energy decreases. The widest applications of these hard ferrites permanent magnets are in motors, speakers sensors and MRI systems.

Nanostructured thin films of carbon were synthesized and investigated for their electrical, optical, structural and surface properties. Pulsed Laser Deposition (PLD) technique was used for the preparation of these films under Argon gas environment. A KrF Laser (λ=248 nm) was used as source of ablation and plasma formation. It was observed that the carbon ions and the background gas environment has deep impact on the morphology as well as on the microstructure of the films. Time of Flight (TOF) method was used to determine the energies of the ablated carbon ions. The morphology of film surfaces deposited at various argon pressure was analysed using an atomic force microscope. The Raman spectroscopic measurement reveal that there is shift in phase from sp3 to sp2 and a decrease in FWHM of G band, which is a clear indication of enhanced graphitic clusters. The electrical resistivity was also reduced from 85.3×10−1 to 2.57×10−1 Ω-cm. There is an exponential decrease in band gap Eg of the deposited films from 1.99 to 1.37 eV as a function of argon gas pressure.

Co and Ni codoped ZnO-based dilute magnetic semiconductors having a general formula of Zn0.9Co0.1−xNixO (x = 0.0, 0.02, 0.04, 0.06, 0.08 and 0.10) have been prepared using a simple solid-state reaction method. A single-phase hexagonal wurtzite structure, confirmed by X-ray diffraction, has been developed for Zn0.9Co0.1−xNixO (x

M-type barium hexa-ferrites having general formula Ba1−xLaxFe12O19 (x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5) have been prepared through conventional ceramic route. The effect of La3+ ions on structural, surface morphological, optical, magnetic, and frequency-dependent dielectric properties has been investigated through X-ray diffractometer, Fourier transmission infrared spectroscopy, scanning electron microscope, UV–visible spectrophotometer, vibrating sample magnetometer, and inductor capacitor and resistance meter, respectively. XRD confirms the hexagonal structure of La3+-substituted Ba hexa-ferrites. FTIR confirmed that bands in the range 500–600 cm−1 might be due to the stretching vibration of oxygen and metal (Fe–O) ions which confirm the formation of hexa-ferrite. The band-gap energy decreases with increasing concentration of La3+ ions. The coercivity increases with the La3+ substitutions due to high magnetocrystalline anisotropy. It is observed that the dielectric constant and conductivity increase, while tangent loss decreases, as the frequency increases.

In this work, Cu+2-doped ZnS semiconductor nanoparticles have been synthesized using co-precipitation route caped with various surfactants such as diethyl-amine (DEA), poly-vinyl alcohol (PVA), cetyl trimethylammonium bromide (CTAB), polyethylene glycol (PEG) and triethyl-amine (TEA). The structural analysis has been carried out by X-ray diffractometer (XRD) and Fourier-transform infrared spectroscopy (FTIR). Morphological and elemental analysis have been performed by scanning electron microscopy (SEM) and X-ray-dispersive X-ray spectroscopy (EDX), respectively. XRD and FTIR have revealed the cubic structure of prepared nanoparticles. The crystallite size has been calculated in the range 15–20 nm through XRD. A hexagonal peak of ZnO is also observed in XRD pattern. The optical and electrical properties have been studied through UV–Vis spectroscopy and Four-point probe technique, respectively. EDX has revealed the presence of S, Cu and Zn as major elements in prepared samples. Optical band gap energy has been estimated in the range 3.6–4.2 eV with absorption edge from 270 to 277 nm. The conductivity of prepared samples has been increased with the decrease in band gap.

In the present work, nickel-doped iron oxide (NixFe3−x O 4) nanoparticles with different concentration of nickel (x = 0, 0.05, 0.1, and 0.15) have been prepared by co-precipitation method. These prepared nanoparticles have been characterized by using x-ray diffractometer, thermo gravimetric analysis and differential scanning calorimetry, Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer, and UV-Visible spectroscopy to study their structural, thermal, morphological, magnetic, and optical properties, respectively. The x-ray diffraction confirms the formation of single-phase inverse spinel cubic structure of NiFe3 O 4 nanoparticles. Crystallite size has been estimated by the full width at half maximum of the most intense x-ray diffraction peak where vibrational and stretching modes of metal-oxygen bonds in 872 cm are shown in Fourier transform infrared spectra which confirms the formation of nanoparticles. The thermal analysis revealed that the transition temperature and stability increases with increasing Ni concentration. The surface morphology indicated that the particles are spherical in shape with some agglomeration. The magnetic measurement revealed that the coercivity and anisotropy increases with nickel doping in magnetite nanoparticles. The optical analysis revealed that direct and indirect both types of band gap increases when the particle size decreases because the absorption spectra shift toward smaller wavelength. The blue shift confirms the formation of nanoparticles.

Crystals of zinc-antimony oxide are synthesized by Solid state synthesis technique. Fine crystals of zinc-antimony oxide are formed by heating the sample at 900 °C for one hour. Crystals are investigated using single crystal X-ray diffraction and found that the compound crystallizes in the tetragonal crystal system with a space group-135, P 42/m b c, indicating primitive tetragonal crystal structure. Crystal structure refinement and ORTEP representation of the zinc-antimony oxide shows two distinct crystallographic oxygen atoms represented by O1 and O 2 ·FTIR spectrum also describe Zn O and Sb O bonds formation and improvement in optical absorption properties.

A series of antimony substituted cobalt ferrites (CoSb 0.3 Fe 1.7 O 4 ) thin films have been deposited employing Electron Beam Deposition technique. The as deposited thin films have been post annealed at different temperature such as 200, 300, 400 and 500 °C. The structural, surface, magnetic and optical properties of as-deposited and post annealed thin films have been studied using X-ray diffractometer, Raman spectroscopy, and Atomic Force Microscope, Vibrating Sample Magnetometer, spectroscopy ellipsometry and UV–vis techniques respectively. The X-ray diffraction and Raman spectroscopy analysis have confirmed the growth of single phase cubic spinel structure in thin films after post annealing. It is observed that the roughness of the thin films decreases and magnetization increases as the annealing temperature increases but not exceeded to as-deposited film. As the post annealing temperature increases the band gap energy increases which shows that the density of defects decreases and structure turn towards crystalline state from amorphous.

Nano crystalline CdS thin films have been deposited on glass substrate employing chemical bath deposition technique by varying thiourea concentration in two different cadmium sources as cadmium chloride (S 1 ) and cadmium acetate (S 2 ). The aim of this research is to investigate the effect of thiourea concentration on optical and structural properties of the deposited CdS thin films. XRD analysis reveals that the CdS thin films fabricated by using S 1 have zinc blende cubic structure and S 2 have hexagonal as well as cubic structure. UV–vis studies demonstrate that as the thiourea concentration increases transmission spectra shift towards the shorter wavelength and optical band gap of CdS thin films also increases from 2.45 to 2.71 eV in S 1 and 2.65–2.74 eV in S 2 . In absorption spectra, a blue shift in the band gap was observed which indicates the formation of CdS nanoparticles measured as 31–9.91 nm in S 1 and 30–15.02 nm in S 2 .

The main objective of the study was to control the degradation rate of material at a higher degradation rate improving the chemical stability of the material. Ta is known to have good chemical resistance, biocompatibility and show no adverse biological response. In the present study, SiO 2 –Na 2 O–CaO–P 2 O 5 bioceramics with different Ta 2 O 5 contents was prepared by solid state sintering method at 1000 °C. The as-sintered ceramics were subjected to immersion studies in stimulated body fluid (SBF) for 21 days under static condition and characterized by XRD, FTIR, SEM, and AAS. The findings of the research indicate that the addition of Ta 2 O 5 controlled degradability, and all samples showed sufficient bioactivity.

The Zn substituted copper chromium spinel ferrites with the chemical formula ZnxCu1−xCr0.5Fe1.5O4 (x = 0–0.8) have been fabricated using powder metallurgical route. The synthesized powders have been investigated by thermal analysis, X-ray diffraction, Fourier transform infrared spectroscopy, Field emission scanning electron microscopy, magnetic and electrical measurement. The X-ray diffraction has confirmed the formation of spinel structure. It has been observed that lattice parameter increases but both the bulk and X-ray density decrease with the increase of Zn concentration. FTIR spectra show two prominent bands in the range of 400–800 cm−1 confirming the formation of spinel ferrites. The saturation magnetization increases up to x = 0.4. As the concentration of Zn increases further, the saturation magnetization decreases. The dielectric tangent loss and dielectric constant (e) decreases while the ac conductivity increases with increasing frequency.

The e-commerce market of Pakistan has phenomenally fostered in recent years as a result of cyberspace expansion and launching of various national and international vendors. While country’s e-commerce scenario has significantly reshaped, customers are still reluctant to adopt e-payment methods and cash on delivery (COD) prevails as the method of payments for online shopping. This study was conducted to empirically investigate major factors which influence Pakistani customers to opt for COD while shopping online. A framework was proposed based on seven constructs and the data were collected using 5-point Likert-type scale. Statistical Package for the Social Sciences (SPSS) v. 22 and Amos v. 23 were used for statistical analysis and structural equation modeling (SEM). Cronbach’s alpha values above .85 were found suggesting good internal consistency. The goodness-of-fit index and adjusted goodness-of-fit index values were observed to be 0.933 and 0.866, respectively. In SEM analysis, perceived security against online scams and perceived control over the buying process were observed to be the key role players instigating Pakistani customers to use COD. Interestingly, perceived trust and perceived satisfaction did not show significant impact. Moreover, the moderator of ease of use positively mediated the influence of perceived security on the use of COD. This study presents imperative implications for online businesses as well as government agencies. The investigation provides an insight into purchase behaviors of Pakistani e-customers and has paramount importance for e-commerce retailers and marketing startups in evolving e-commerce scenario of the country.

The thin films of Ti0.9F0.1-xCrxO2 (x = 0.0, 0.02, 0.04, 0.06, 0.08, 0.1) have been deposited on Si (100) substrate by pulsed laser deposition (PLD) technique at substrate temperature of 630ᶱC. The deposition time was 60 min. The synthesized samples have been characterized by X-Ray diffractometer (XRD) for structural study, Atomic force microscopy (AFM) and Scanning electron microscopy (SEM) for surface analysis, EDX for elemental composition, Vibrating sample magnetometer (VSM) for magnetic properties, Spectroscopic ellipsometry (SE) for optical properties and four probe Hall effect measurements for electrical properties. Structural analysis revealed pure phase of rutile without any secondary peak. AFM and SEM measurements revealed decrease in crystallinity and increase in grain size. Magnetic characterization showed ferromagnetic behavior for all thin films at room temperature. Optical characterization revealed red shift in band gap energy with increasing amount of Cr concentration. Semiconducting behavior with n- type carriers is observed from electrical measurements.

The main purpose of this research work is to develop the single domain magnetic particles of M-type barium hexaferrite (BaFe12O19) using oxide precursors employing conventional powder metallurgy technique. The phase formation and magnetic performance of the powders and magnets will be optimized by adjusting calcination and sintering temperatures. The synthesis of M-type barium hexaferrite was carried out in two sections. A series of four samples have been prepared by initial wet mixed powders calcined at different temperatures, i.e., 750, 850, 950 and 1050 °C. On the basis of structural analysis, the sample calcined at 950 °C has been selected and further divided into four parts to sintered them at 1100, 1150, 1200 and 1250 °C. The structural measurements depict the confirmation of M-type barium hexaferrite structure. SEM micrographs show the hexagonal-shaped grains. The abrupt decrease in coercivity for the sample sintered at 1250 °C has been seen which may be due to high sintering temperature, at which the particles have multi-domain properties.

A series of Ti0.9Fe0.1-xCrxO2 (where x = 0.0, 0.02, 0.04, 0.6, 0.08, 0.10) was synthesized using the powder metallurgy route. The structural, morphological, magnetic, optical and electrical properties were investigated by X-ray diffractometry (XRD), Raman spectroscopy, scanning electron microscopy (SEM), vibrating sample magnetometry (VSM), UV-Vis spec­troscopy and four probe technique, respectively. The rutile phase was confirmed by XRD analysis which was also verified by Raman spectroscopy. It was observed that the grain size increased as the concentration of Cr increased. M-H loops ex­tracted from VSM analysis revealed anti-ferromagnetic, weak ferromagnetic and paramagnetic behaviors at room temperature. The band gap energy and resistivity measurements exhibited the semiconducting nature of Ti0.9Fe0.1-xCrxO2 based diluted magnetic semiconductors.

A bioactive ceramic in (48− x ) SiO 2 –36CaO–4P 2 O 5 –12Na 2 O– x TiO 2 (where x = 0, 3.5, 7, 10.5 and 14 mol%) system was prepared by solid state sintering method. The in vitro bioactive properties of bodies were evaluated using stimulated body fluid under static condition at 37 °C. The formation of hydroxyl-carbonated apatite layer on the surface of samples was examined by XRD, FTIR, SEM and AAS. It was found that partial substitution of SiO 2 with TiO 2 produced a positive impact on the bioactivity of the specimens. Addition of TiO 2 ≤10.5 mol% to the system not only enhanced the bioactive properties but also accelerates the apatite forming process.

This project is aimed to the fabrication of thin films of chromium-substituted cobalt ferrites (CoCr0.5Fe1.5O4) by electron beam deposition technique. After deposition, the thin films are post annealed at 200, 300, 400, and 500 ℃ for 1 h. The structural properties of thin films are investigated by X-ray diffraction (XRD) and Raman spectroscopy which confirm the inverse cubic spinel structure. It is revealed that the films become more crystalline as annealing temperature is increased. The films showed smooth surface morphology with RMS roughness of

Antimony doped cobalt ferrite with general formula CoSbxFe(2-x)O4 (with x=0.0, 0.1, 0.2, 0.3, 0.4, 0.5) have been synthesized by powder metallurgy method. The structural, chemical, microstructural, magnetic and optical properties have been investigated using XRD diffractometer, Fourier Transform Infra-red Spectroscopy, Scanning Electron Microscope (SEM), Vibrating Sample Magnetometer (VSM) and UV-Visible Spectrometer respectively. XRD micrographs of all the samples have been confirmed the formation of spinel structure having major peaks at (220), (311), (400), (422), (511), (440). The increase in lattice parameter is due to the replacement of smaller cation Fe+3 by larger cation Sb+3. FTIR analysis shows major bond (M-O) vibrational bond confirms the spinel structure. When the concentration of antimony is zero then the value of saturation magnetization is 45.5emu/gm. But there is a sharp increase in Ms at x=0.1, this is due to the doping of Sb. The Co+3 and Sb+3 ions prefer to occupy the site B. After that there is decrease in Ms from x=0.2-0.4 this is may be due to the possible concentration of Sb+3 to the site A as compared to octahedral site. The band gap energy decreases as the antimony concentration increases which is associated with the decrease in grain size.

Three samples of dilute magnetic semiconductors (DMS) have been prepared by solid state reaction method at sintering temperature of 950 °C for 5 hours. Their structural, optical, electrical and magnetic properties are optimized by X-Ray Difractometer (XRD), UV-Visible spectrophotometer (UV-Vis), Four point probe method and Vibrating sample magnetometer (VSM) measurements respectively. Surface morphology has been studied by using scanning electron microscope (SEM). Structural analysis showed that a single phase Rutile structure has been attained while Optical and resistivity measurements confirmed their semiconducting behaviors. Magnetic measurements showed weak Ferromagnetic and Paramagnetic behaviors at room temperature.

Samples of composition Zn 0.9 Co 0.1 O, Zn 0.9 Ni 0.1 O, Zn 0.9 Co 0.06 Ni 0.04 O were prepared by powder metallurgy method. Structural property was studied by X-ray diffractometer (XRD), and Fourier transform infrared spectroscopy (FTIR). Magnetic, electrical and optical properties were studied by vibrating sample magnetometer (VSM), four point probe method and UV-Visible spectrophotometer, respectively. Single phase wurtize structure was obtained for Zn 0.9 Co 0.1 O and Zn 0.9 Co 0.06 Ni 0.04 O, while a secondary phase of NiO was found in Zn 0.9 Ni 0.1 O. The bandgap energy found in all samples was less than pure ZnO. Scanning electron microscope (SEM) studied surface Morphology. Moreover, room temperature ferromagnetism (RTFM) was observed for all samples.