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The synthesis of Ce doped ZnO nanoparticles exhibits the enhancement of results and its favor to electronic properties. The minimum average crystal size was obtained from 8 wt% (8 nm). The weight percentage (wt%) of cerium doping concentration increases, average crystal sizes are decreased upto 8 wt% and then crystal size increased for 10 wt% of doping level. The UV–Visible spectra analysis shows that the high absorbance and broad peak obtained at 8 wt%. PL studies exhibits the enhanced intensity of the broad emission at green region confirms that the increased density of defects which can be attributed to the oxygen vacancy created by the existence of Ce doped in ZnO nanoparticles. At last we got minimum band gap energy value of 1.32 eV at 8 wt% of Ce doped ZnO nanoparticles. VSM studies showed room temperature ferromagnetism in the Ce-doped ZnO NPs. The polarization esteems are seen as diminished with the expansion in Ce fixation in ZnO after 4 wt% and 6 wt% Ce. The watched ferromagnetism in Ce–ZnO NPs is because of the nearness of Ce3+ particle state and oxygen opening and interstitial destinations of Zn.

The present work synthesis pure and Sn doped ZnO-NPs by solid state reaction method is reported to develop ZnO-NPs for magnetic application. The synthesized nanoaprticles were characterized by structural (X-ray), optical (UV–Vis), morphological (SEM with EDAX), functional group analysis (FT-IR) and PL spectroscopy. The X-ray diffraction analysis of Sn doped ZnO-NPs confirmed hexagonal wurtzite strcture of ZnO with minimum crystal size about 32.7 nm. UV–visible analysis shows that the Sn concentrations increased the amount of the catalyst and the formation of defects increased. The SEM study reveals the surface and ultra structure morphology of synthesized nanoparticles. To examine the various functional groups FT-IR was utilized. Due to annealing effect, Sn doped ZnO-NPs shows higher saturation magnetization at room temperature.

The pure and different parentage of copper doped ZnO nanoparticles were synthesized by solid state method. The synthesized nanoparticles were characterization of XRD, SEM, FT-IR, UV–Vis and PL technique. The XRD studies exhibited the good crystalline nature in different nanometer range crystal size with different doping percentage of copper. SEM micrograph shows that the well- dispersed highly agglomerated, accompanying almost well-defined crystalline nature and rod shaped ZnO nanoparticles. The PL spectra for ZnO (pure) and Copper doped ZnO nanoparticles is the formation of a new broad peak at 505 nm arises from the widening or redshift effects of the pre-existing peak at 381 nm. This confirms the enhanced visible light optical activity observed with (8%) Cu-ZnO-Nanoparticles.

In the present work, pure and copper composite zirconium oxide nanoparticles with a different percentages of copper (0.02, 0.04, 0.06 and 0.08%) were successfully synthesized by a low cost sol–gel technique. It was found that as-prepared samples of copper-composite (zirconium oxide) ZrO2 nanoparticles are in monoclinic phase. The copper-doped zirconium oxide (ZrO2) NPs are present as spherical morphology and highly agglomeration confirmed by scanning electron microscopy and high resolution transmission electron microscope analyses. The synthesis samples exhibited two bandgap energy at 3.6 eV and 2.6 eV, 3.57 eV and 2.4 eV, 3.55 eV and 2.14 eV, and 3.5 eV and 2.1 eV. The presence of functional groups and the chemical bonding is confirmed by FT-IR spectra. PL spectra of the pure and Cu-doped ZrO2 nanoparticles exhibited oxygen vacancies. Voltage–current characteristics of pure and composite ZrO2 nanoparticles are studied at vary incident light intensity that show the negative photoconductivity.

Swift heavy ion (SHI) beam irradiation can generate desirable defects in materials by transferring sufficient energy to the lattice that favours huge possibilities in tailoring of materials. The effect of Ag15+ ion irradiation with energy 200 MeV on spray deposited V2O5 thin films of thickness 253 nm is studied at various ion doses from 5 × 1011 to 1 × 1013 ions/cm2. The XRD results of pristine film confirmed orthorhombic structure of V2O5 and its average crystallite size was found to be 20 nm. The peak at 394 cm−1 in Raman spectra confirmed O–V–O bonding of V2O5, whereas 917 cm−1 arise because of distortion in stoichiometry by a loss of oxygen atoms. Raman peaks vanished completely above the ion fluence of 5 × 1012 ions/cm2. Optical studies by UV–Vis spectroscopy shows decrement in transmittance with an increase in ion fluence up to 5 × 1012 ions/cm2. The red shift is observed both in the direct and indirect band gaps until 5 × 1012 ions/cm2. The surface topography of the pristine film revealed sheath like structure with randomly distributed spherical nano-particles. The roughness of film decreased and the density of spherical nanoparticles increased upon irradiation. Irradiation improved the conductivity significantly for fluence 5 × 1011 ions/cm2 due to band gap reduction and grain growth.

Lanthanum-doped cobalt nanoferrites CoLaXFe2−XO4 (X = 0.00 to 0.08) were synthesized by using sol–gel method. A cubic spinel structure was confirmed by using X-ray diffraction pattern. A band obtained at 583 cm−1 recorded by Fourier transform infrared spectrum confirmed the presence of metal oxide spinel nanoferrites. The bandgap energy has increased with addition of La3+ ions by using ultraviolet diffuse reflectance spectrum. The grain boundary contribution is greater than that of grain contribution due to small crystal size, which was confirmed by an impedance analysis. The dielectric constant and dielectric losses decreased with increasing frequencies. The binding energy of La, Co, Fe and O were determined by X-ray photoelectron spectroscopy. The magnetic studies were analyzed through vibrating sample magnetometer. The hysteresis loop revealed the soft ferromagnetic nature.

Lanthanum doped manganese spinel nanoferrites (MnLaXFe2-XO4) with X = 0.00, 0.02, 0.04, 0.06 and 0.08 were fabricated by sol-gel method. The cubic phase was confirmed by using X-ray diffraction technique. FESEM revealed that the prepared samples attain highly stable spherical morphology. Energy dispersive X-ray spectra confirm the presence of Manganese (Mn), Lanthanum (La), Iron oxide (Fe) and oxygen (O) element in desired proportion. Ultra-violent diffuse reflectance spectroscopy shows that absorbance spectra were inversely proportional to band gap energy. Room temperature magnetic hysteresis curves expose the ferromagnetic behavior with decreases of saturation (Ms) and increases of coercivity (Oe). The origin of ferromagnetism in La3+ doped manganese nanoferrites were elaborated with reverence to the allocation of Mn2+ and Fe3+ ion within the spinel lattice. An impedance spectroscopy of the samples were analyzed in the frequency ranges from 0 to 7 MHz at room temperature reveals the resistance of the grains and grain boundary were found to increase with La3+ ion. The dielectric constant and loss tangent decreases with increases of frequency. The obtained results confirm that the prepared samples were useful for better radiation-absorption properties.

A simple and modified chemical precipitation method is used for synthesis of different PEG assisted cadmium oxide nanoparticles. The prepared products were characterized by X-ray diffraction, Fourier transform infrared, ultraviolet, scanning electron microscopy and energy dispersive X-ray analysis. The XRD patterns revealed the cubic phases and calculated particle sizes are 36.42, 34.27, 33.54 and 35.21 nm for pure CdO with 2, 4 and 6 % PEG nanoparticles respectively, From these results, it can be observed that the average crystalline size decreases with increasing PEG concentration. The functional groups and band area of the product were established by FT-IR spectroscopy. The band gap energy of CdO nanoparticles increased from 2.54 to 2.94 eV by increasing PEG concentration .The surface morphology and element composition have been confirmed form SEM with EDX analysis. In addition, the photocatalytic performance of PEG assisted CdO nanoparticles with methylene blue indicated that the CdO can be utilized a good photocatalyst for degradation of methylene blue.

The present work was undertaken to develop silver nanoparticles by a simple chemical route using harmless surfactant polyvinylpyrrolidone (PVP) at four different temperatures viz., 200 °C, 300 °C, 400 °C and 500 °C. Effect of temperature on structural, morphological and antibacterial properties was investigated. The XRD pattern confirmed the crystallinity and pure phase of the Ag-NPs. Also it is confirmed that the size of the Ag[PVP] nanoparticles was affected by the temperature. The FT-IR analysis indicated the functional groups of PVP coordinate with silver ions and bind on surface of Ag-NPs. EDAX confirmed the formation of Ag nanoparticles without a trace of impurities. The SEM images showed the formation of spherical Ag[PVP] nanopowder in which the average particle size ranges from 20 nm to 34 nm. The antibacterial potential of synthesized Ag[PVP] nanoparticles was carried out against four different bacterial pathogens and show significant bacterial resistance.

Copper oxide nanoparticles were synthesis by sol-gel method using Lantana camara extract as a mixture of CuCl2 2H2O and NaOH. CuO NPs to be investigated by XRD, UV Spectra, SEM, FTIR, Photocatalytic activity. X ray diffraction revealed that they were crystalline in nature and the average size of nanoparticles was 17 nm as determined by Scherrer Formula. The photocatalytic performance of these nanoparticles was evaluated using methylene blue dye. The result showed that photocatalytic performance was 94.07% depending on the particle size of the CuO nanoparticles.

Swift Heavy Ion (SHI) beam irradiation has been used as an experimental technique to modify the material properties through the interaction of the ion beam with the target material. In this work, the properties of the pristine and 200 MeV Ag15+ ion beam irradiated lithium (3 wt%) doped WO3 (tungsten trioxide) thin films are reported. These thin films were spray deposited onto ITO coated glass substrates at 400 °C with thickness around 55 nm and irradiated with the 200 MeV Ag15+ ion beam at a fluence of 5 × 1012 ions/cm2. The XRD pattern of pristine film confirmed textured growth along the (211) plane with tetragonal phase, while the irradiated film was partially amorphous. Raman modes at higher wavenumbers 708 cm−1 and 806 cm−1 belong to W–O stretching modes, whereas modes at lower wavenumbers 133 cm−1 belong to lattice mode and 265 cm−1 are associated with W–O bending modes for pristine film. Upon irradiation, all the Raman modes vanished due to irradiation induced amorphization. The optical transparency of the film upon irradiation decreased significantly, and band gaps showed a red shift. The atomic force microscopy (AFM) images of pristine film surfaces were homogeneous, smooth and free from holes with small grains, whereas ion irradiated films exhibited isolated flattened particles of varying size on the surface. Room temperature transport properties were also measured using Hall effect for both the pristine and irradiated films.

Pure and Cd-doped ZnS nanoparticles were synthesized by inexpensive solid state reaction method at different percentages (0.5, 1.0, 1.5 and 2.0 wt.%). The structural, functional, optical, morphological and photocatalytic properties were characterized by using X-ray diffraction analysis, Fourier transform of infrared (FT-IR) spectroscopy, UV–Vis spectroscopy, photoluminescence (PL) spectroscopy and scanning electron microscopy (SEM) were done using energy dispersive X-ray analysis. In XRD pattern crystalline size, microstrain, dislocation density and lattice constant were found and they confirmed the crystalline nature with cubic structure. SEM and TEM exposed the great quantity of sphere-shaped particles and the elements Zn, S and Cd were identified from EDS. The photo-degradation rate was sturdily inclined by activation of ZnS photocatalyst with photon and creation of hydroxyl radicals. This suggested that Cd doping enhanced catalytic activity in the ZnS lattice.

In this present work, effects of cerium (Ce)-doped CdO nanoparticles (NPs) were synthesized by simple chemical precipitation methods. The as-formed CdO-NPs were characterized by crystal structure (XRD), surface morphology (SEM), elemental composition (EDX), functional groups (FTIR) and optical spectroscopy (UV-DRS and PL) analysis. The XRD indicated cubic in structure of CdO-NPs that were as well crystallized with an averaged particle size of 28–33 nm. The SEM images show concise structure of CdO-NPs, and EDX spectrum revealed the presence of cerium. FTIR spectra show the fundamental peaks of CdO in the sample. The optical properties showed that the two emission peaks were recorded at 418 and 439 nm upon excited at 360 nm. The photocatalytic degradation efficiency of methyl orange dye, i.e., 93% at the optimum content of Ce3+-doped (5%) CdO-NPs.

Copper(II) oxide (CuO) nanoparticles synthesized by different molarities like 0.1, 0.2 and 0.3 M at calcinations temperature 450 ºC. The XRD results analyzed the prominent peaks corresponding to the monocrystalline nature of CuO nanoparticles and the average crystalline size of CuO nanoparticles size is decreased with increase of molarities. From SEM image of CuO nanoparticles, the particles are well scattered, which are well connected and consistent with the crystal system. The absorption spectra shows the blue shift which can be attributed to the small size of CuO nanostructures. The FTIR spectra confirmed high intense broad band peaks at 496.96 cm-1 and assigned to characteristics band of monoclinic phase CuO nanoparticles were synthesized and calcined at 450 ºC, and the particle size of the nanoparticles was found to be in the range of 19-23 nm. These sizes of integrated CuO nanoparticles is a cost-efficient, biological molecule capable of working with antibiotics against Staphylococcus saprophyticus, Bacillus subtilis, Pseudomonas aeruginosa and Escherichia coli.

The physical properties of thin films can be modified by swift heavy ion (SHI) beam irradiation of the target material. Spray-deposited tungsten trioxide (WO3) thin films of thickness 89 nm were irradiated with 200 MeV Ag15+ ion beam at various fluences of 5 × 1011, 1 × 1012, 5 × 1012, and 1 × 1013 ions/cm2. The X-ray diffraction pattern of the pristine film was orthorhombic, while the irradiated film became amorphous at different fluences except for 5 × 1012 ions/cm2; this may be due to the re-crystallization effect induced by irradiation. The observed Raman modes for the pristine film were in good agreement with those reported for the irradiated WO3 films. The intensity of Raman peaks decreased upto 5 × 1012 ions/cm2 and vanished completely at further higher fluences. The optical transparency of the pristine film was much higher than that of irradiated ones. Both the direct and indirect band gaps showed a red shift. AFM data revealed significant surface modifications after irradiation. Transport properties were also studied for both the pristine and irradiated films by the Hall effect. A decrease in resistivity was observed with the increase in fluence. These results are discussed in this paper.

Pure and Ni (0.5–2.0%) doped ZnS nanoparticles were prepared by an inexpensive solid state reaction method. The structural, functional, optical, morphological and chemical compositions of the products were characterized by XRD, FT-IR, UV–Vis, PL, SEM with EDX and TEM analyses. The X-ray diffraction results confirmed that the polycrystalline nature with cubic crystal structure of the nanoparticles. Also, using these data, crystallite size, dislocation density, micro-strain, stacking fault and lattice constant were calculated. The functional group associated with the vibration of a molecule was investigated by FTIR spectroscopy. The optical band gap was increased from 3.58 to 3.97 eV with increasing Ni dopant concentrations. The SEM and TEM images depict the nanosized particles with spherical shape morphology. The elemental composition of Ni-ZnS nanoparticles was examined by EDX analysis. The PL emission spectra show an intensity quenching upon Ni doping and exhibit green emission in the visible region. The photocatalytic activity results indicated that the Ni doping enhanced the photocatalytic activity of ZnS. Thus, Ni-ZnS could be effectively used as photocatalyst for degradation of environmental pollutant Methylene Blue dye.

Nickel oxide nanoparticles have been synthesized via simple hydrothermal method. The structural, morphological, optical and magnetic properties of the as-synthesized products were examined by X-ray diffraction (XRD), scanning electron microscope, UV–Vis spectroscopy, photoluminescence (PL) and vibrating sample magnetometer (VSM). XRD patterns of pure cubic structured NiO nanoparticles were revealed with average grain size of 13 nm. The optical band gap was found to (3.69, 3.66 and 3.64 eV) decreases with increasing molar concentration of the precursor. PL spectra at room temperature showed a strong blue emission band and thereby confirm the above results. VSM results demonstrate that the NiO samples exhibit perfect room temperature ferromagnetism.

Cobalt doped Sn2S3 thin films with a dopant concentration of 1, 2 and 3 at. wt% have been coated on glass substrate by spray pyrolysis method and the structural, optical, electrical and magnetic properties of the film investigated. XRD pattern confirms the polycrystalline nature of the films and the preferential orientation of the crystal is along the (211) direction. The band gap energy of the undoped film is 1.77 eV and can be tailored by the addition of Co atoms. The absorption coefficient of all the films is of the order of 104 Ωcm−1 near the fundamental absorption edge and is very much suitable for photovoltaic applications. The electrical conductivity increases due to cobalt addition and is maximum for a concentration of 2 wt%. The presence of Cobalt in Sn2S3 thin film introduces ferromagnetic properties even at room temperature. Addition of Cobalt in Sn2S3 has improved its optical and electrical properties and also paved the way for its use as a dilute magnetic semiconductor (DMS).

Molybdenum trioxide doped with 5 wt% lithium was deposited using indigenously built spray pyrolysis unit onto ITO coated glass at a substrate temperature of 325 °C. The XRD patterns revealed the pristine film to have orthorhombic structure while partial amorphization to take place in the film irradiated with O7+ ion beam. The Raman peak at 996cm−1 confirms the deposited film to belong to orthorhombic phase which is due to the stretching vibration of the terminal oxygen atoms (Mo6+=O). Lower transmittance was observed for both the films and a red shift in band gap was observed for the irradiated compared to the pristine film. Transport properties were also studied for both the pristine and irradiated films and the results are discussed in detail.

Sn 2 S 3 Nano crystalline thin films were deposited by spray pyrolysis technique onto glass substrates for three different temperatures 320 °C, 360 °C and 400 °C and the effect of substrate temperature on the structural, compositional, electrical and optical properties of Sn 2 S 3 thin film were investigated. X-ray diffraction analysis (XRD) confirmed the formation of single phase polycrystalline Sn 2 S 3 crystals in the preferential direction (211). With increase in substrate temperature the film thickness was observed to increase and the crystals became smaller in size. SEM images confirmed a uniform, homogeneous coating of Sn 2 S 3 thin film with needle shaped Nano crystals at 400 °C. The EDX (Energy Dispersive X-ray) analysis depicted the films were non-stoichiometric due to the evaporation of sulphur at higher temperatures. From UV-Vis-NIR spectroscopy studies the absorption coefficient of the film was determined to be of the order of 10 4 cm −1 and the refractive index and dielectric constants obtained indicated a normal dispersive film. The electrical properties were investigated by Hall measurements at room temperatures and a resistivity of the order of 10 −1 Ωcm and carrier concentration in the range of 10 16 cm −3 were observed. Sn 2 S 3 thin films sprayed at 400 °C are a potential candidate as n-type absorber layer in thin film photovoltaic cells.

In the present work, high purity ZnO nanorods were synthesized by solid state reaction method at different annealing temperatures (250–400 °C). The structural, morphological and optical characteristic of the ZnO nanorods were studied. X-ray diffraction results confirmed that the ZnO nanorods have Wurtzite structure with high crystal quality. The grain size has increased from 23 to 27 nm with increasing temperature. The scanning electron microscopy and high resolution-transmission electron microscopy photographs showed the formation of ZnO nanorods. The bonding natures of the synthesized nanorods were analyzed by Fourier transform infra-red spectroscopy. The blue shift in the absorption edge was observed from the UV–Vis spectrum. The photoluminescence spectra showed two emission peaks corresponding to blue and red emissions. The photocatalytic performance of these nanorods was evaluated using methyl violet dye. The result showed that photocatalytic performance is highly depends on the morphology of the nanorods.

Nano-crystalline particles of CeO2 have been synthesized by a low temperature hydrolysis method. The structural, morphological and optical properties were characterized by using X-ray diffraction (XRD), FT-IR, scanning electron microscopy (SEM) with energy dispersive spectroscopy and UV–Vis spectra. XRD pattern confirmed the crystalline nature and cubic structure of synthesized composition. The size of CeO2 nanoparticles increases with increase in concentration. The functional groups present in the sample were identified by FTIR spectroscopy. The microstructure and elemental identification were done by SEM with EDX analysis. The band gap energy is found to increase from 3.15 to 3.28 eV with increase in concentration.

Zinc oxide nanorods were prepared at 3, 6, 9 and 12 h by using solid state reaction method with appropriate reactants. The structural, optical and morphological properties of the synthesized samples were investigated. The XRD analysis revealed that the nanorods were polycrystalline in nature and having hexagonal wurtzite crystal structure with a preferred grain orientation along (101) direction. The optical band gap energy values were increased from 3.35 to 3.50 eV with increase in annealing temperatures. From the PL spectra, the strong red emission and weak blue emission were observed. The functional groups present in the samples were identified by FTIR spectroscopy. The microstructure and elemental identifications were done by SEM and TEM with EDX analysis. The photocatalytic performance of the ZnO nanorods was evaluated using methyl violet dye as a model contaminant.

Pure Zinc sulfide nanoparticles were synthesized by an inexpensive Solid state reaction method using zinc acetate and thiourea at different temperatures (250–450 °C). The structural, functional, optical and morphological properties were characterized by using X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, UV–Vis spectroscopy, Photoluminescence (PL) spectroscopy and Scanning electron microscopy (SEM) with Energy dispersive X-ray analysis. XRD patterns confirmed the crystalline nature and cubic structure of the prepared products. Crystallite size, microstrain and dislocation density were also evaluated from the XRD data. The functional groups present in the samples were investigated by FTIR study. A blue shift in the absorption edges was noticed in the UV–Vis spectra. The PL spectra showed three emission peaks corresponding to both UV and visible emissions. SEM revealed the abundance of spherical shaped particles and the elements Zn and S alone are identified from EDS.

Undoped and Zn-doped Sn2S3 thin films were fabricated by spray pyrolysis technique on glass substrates kept at 400 °C. All the films exhibited orthorhombic crystal structure with a preferential orientation along the (2 1 1) plane. Nanoplate structures were observed from the SEM images and the presence of Zn in the doped films was confirmed from the EDX spectra. The average optical transmittance of all the films in the visible region was found to be nearly equal to 80 %. Film resistivity initially decreased from 3.27 × 10−1 to 0.78 × 10−1 Ω-cm for the Sn2S3 thin film doped with 1 wt% Zn concentration and for higher doping concentration it increased. The obtained results showed that the Sn2S3 thin film doped with 1 wt% Zn concentration had better physical properties which made them suitable for photovoltaic applications.

Nanostructured Ni-doped Sn2S3 thin films with Ni concentrations (0, 1, 2 and 3 wt.%) were prepared on glass substrates by spray pyrolysis technique at 400 °C. From the structural studies, it is observed that both the undoped and doped films exhibit orthorhombic crystal structure with (2 1 1) preferential orientation. Crystallite size increased from 22.94 to 27.80 nm with Ni doping. SEM images confirmed the presence of nanoneedles in the doped films. Film transparency increased with doping and optical band gap is found to be blue shifted which is related to Burstein–Moss (BM) effect. All the films have resistivity in the order of 10−1 Ω-cm, which decreased with Ni doping. From the structural, morphological, optical and electrical properties, it is observed that the Sn2S3 film coated with 2 wt.% Ni doping had better physical properties.

Nano needle structured Cu-doped Sn 2 S 3 thin films with different Cu concentrations (0, 1, 2 and 3 wt.%) were prepared by spray pyrolysis technique on glass substrates maintained at 400 °C. XRD analysis showed that the undoped and doped Sn 2 S 3 films exhibit orthorhombic crystal structure with a preferential orientation along the (2 1 1) plane. SEM images confirm the presence of nano needles in both the undoped and doped films. Optical band gap is red shifted from 1.96 eV to 1.86 eV with increase in Cu concentration in the films which may be attributed to Moss-Burstein effect. All the films have resistivity in the order of 10 −1 Ω-cm and the Sn 2 S 3 film coated with 2 wt.% Cu concentration exhibit a minimum resistivity of 0.335 × 10 −1 Ω cm. The obtained results infer that Sn 2 S 3 film coated with 2 wt.% Cu concentration exhibit better physical properties.

The present work demonstrates the effect of Ni doping on the, structural, optical, morphology behaviour, as well as the photocatalytic degradation efficiency of Methylene blue (MB) and Methylene orange (MO) by cadmium sulfide (CdS) nanoparticles. The different percentages (0.5, 1.0, 1.5 and 2.0%) of Ni doping CdS nanoparticles are successfully synthesized with average crystalline size from 8.70 to 9.93 nm by sol gel method. The SEM image were combination of metal oxide cubes and rod-like structures with 12-35 nm unequal grain size results in excellent crystalline quality. Optical properties of the sample revealed that the band gap energy decreased from 2.36 to 2.29 eV with an increase in Ni doped percentage. Furthermore, photocatalytic degradation of MB and MO dyes under sunlight irradiation using Ni doping CdS nanoparticles was performed. The prepared nanoparticle shows 94% degradation activity for MO dye for 75 min. Now a days, sol gel method has attracted a great attention for the production of nanocparticles due of its simplicity and cost effective nature.

Nanostructured zirconium oxide (ZrO2) thin films were deposited at various substrate temperatures (275–475 °C) through spray pyrolysis technique. The X-ray diffraction pattern of the products was indexed to the tetragonal phase of ZrO2 and the crystallite size of the films increased by increasing substrate temperature. The Raman spectrum confirmed the crystalline structure of the sample. The spherical shape morphology of the materials was obtained by scanning electron microscopy and verified using transmission electron microscopy. The energy dispersive X-ray analysis indicated that the elemental ratio (Zr:O = 33.76:66.24) was similar to ZrO2. The selected area electron diffraction pattern reveals the well-crystallized tetragonal form. From the UV–Vis spectra, the observed band gap values were increased with increase of substrate temperatures. The photoluminescence spectra showed emission peaks corresponding to blue emission. Mainly, the photocatalytic activity of the ZrO2 catalyst was tested using methylene blue (MB) dye as a model contaminant for environmental remediation. The percentage degradation increases rapidly with the increase in time for MB-ZrO2 solution.

Pure indium oxide (In2O3) nanoparticles was synthesized by an inexpensive and solid state reaction method using indium nitrate in muffle furnace at 400 °C for 4 h. The synthesized product was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, FT-Raman, scanning electron microscopy (SEM) with energy dispersive spectroscopy, high resolution transmission electron microscopy (HR-TEM), photoluminescence (PL) and UV–Vis spectroscopy. XRD pattern confirmed the crystalline nature and cubic structure of synthesized composition. Crystallite size, microstrain and dislocation density were evaluated from the XRD data. The functional groups present in the sample were identified by FT-IR spectroscopy. The vibrational modes of the product were investigated by FT-Raman spectrum. The microstructure and elemental identification were done by SEM with EDX analysis. The HR-TEM image depicts the morphology and size of the prepared nanoparticles. The blue shift in the absorption edge was observed from the UV–Vis spectrum. The PL spectrum showed two emission peaks corresponding to blue emission.

Undoped and zirconium doped indium oxide (ZrIO) thin films were deposited on glass substrate at a substrate temperature of 450 °C by spray pyrolysis method. The effect of zirconium (Zr) dopant concentration (0–11 at.%) on the structural, morphological, optical and electrical properties of n-type ZrIO films were studied. X-ray diffraction (XRD) results confirmed the polycrystalline nature of the ZrIO thin film with cubic structure. The grain size was decreased from 25 to 15.75 nm with Zr doping. The scanning electron microscopy (SEM) showed that the surface morphology of the films were changed with Zr doping. The surface roughness of the films was investigated by atomic force microscopy (AFM) and was found to be increased with the increasing of Zr doping percentage. A blue shift of the optical band gap was observed. The optical band was gap decreased from 3.50 to 3.0 eV with increase in Zr concentrations. Room temperature photoluminescence (PL) measurement of the deposited films indicated the incorporation of Zr in In2O3 lattice. The film had low resistivity of 6.4 × 10−4 Ω cm and higher carrier concentration of 2.5 × 1020 was obtained at a doping ratio of 7 at.%.

Swift Heavy Ion beam irradiation is capable of inducing a variety of modifications on the properties of thin films by high energy deposition. The Nb2O5 thin films deposited by spray pyrolysis technique were then irradiated with 200 MeV Ag15+ ions at fluence ranging from 5 × 1011 to 1 × 1013 ions/cm2. The thickness of the deposited film was 308 nm and the irradiated area was 1x1 cm2. The XRD pattern of the pristine film confirmed the tetragonal structure of Nb2O5. Upon irradiation, peak intensity decreased significantly and some peaks vanished due to irradiation induced defects. The subtle Raman peaks around 960, 223, and 126 cm−1 corresponds to edge shared octahedra, T2u mode and Nb–Nb vibration respectively. After irradiation, complete suppression of vibration modes was observed except for 1 × 1012 fluence. For the 1 × 1012 ions/cm2 fluence, Raman modes reappear with increased intensity due to irradiation induced recrystallization. Optical transmittance spectra showed a decreased trend as fluence increased due to the formation of optically absorbing centers. Both the direct and indirect band gaps showed a systematic red shift. The pristine AFM image revealed agglomeration of particles while a network like structure was observed after irradiation. Results of transport properties studied for both pristine and irradiated films at room temperature by Hall effect are also presented.

Indium oxide (In 2 O 3 ) thin films are successfully deposited on microscopic glass substrate at different temperatures by spray pyrolysis technique using Indium acetate as precursor solution. The physical properties of these films are characterized by XRD, SEM, AFM, UV–visible, PL and Photo acoustic measurements. XRD analysis revealed that the films are polycrystalline in nature having cubic crystal structure with a preferred grain orientation along (2 2 2) plane. The average transmittance in the visible region is found to vary from 60% to 93% depending upon the substrate temperature. The complete vibrational analysis has been carried out and the optimized parameters are calculated using HF and DFT (LSDA, B3LYP and B3PW91) methods with 3-21G(d,p) basis set for In 2 O 3 . The fundamental frequencies are calculated and assigned according to the experimental frequencies. Furthermore, 13 C NMR and 1 H NMR chemical shifts are calculated by using the gauge independent atomic orbital (GIAO) technique with HF/B3LYP/B3PW91 methods on same basis set. A study of the electronic properties; absorption wavelengths, excitation energy, dipole moment, Kubo gap (HOMO and LUMO) and frontier molecular orbital energies, are performed by HF and DFT methods. Besides frontier molecular orbitals (FMO), molecular electrostatic potential (MEP) is executed. The thermodynamic properties (heat capacity, entropy, and enthalpy) of the compound are calculated in gas phase.

Measurements of surface ozone (O3) and nitrogen dioxide (NO2) were studied from December 2004 to February 2005, covering the giant tsunami event on 26 December 2004 at Tranquebar (11° N, 79.9° E, 9 m) over the west coast of the Bay of Bengal, India. An unusual maximum O3 concentration of 28 parts per billion by volume (ppbv) was observed in the morning and a minimum (16 ppbv) in the evening, indicating that pronounced chemical loss of O3 occurred in the daytime after the tsunami over this coastal region. An increase in NO2 concentration from 5.6 ppbv before the tsunami to 10.5 ppbv after the tsunami was observed in the daytime. The observed unusual diurnal changes in O3 were not due to mass transport processes as the five-day back trajectories of air parcels transport before and after the tsunami remained unchanged. Similarly, meteorological and micrometeorological parameters were found to be normal before and after the tsunami. The unusual low O3 level during the daytime was possibly due to prolonged excess emission of iodocarbons from the sea surface after the tsunami, which resulted in enhanced inorganic iodine (Ix) concentration, leading to massive destruction of O3. Similarly, unusually high O3 levels during the night-time were possibly due to the intrusion of ozone-rich air after the tsunami from the free troposphere into the surface layer when the boundary layer height shrinks after midnight. The present work can be extended on a regional scale by incorporating modelling studies using recent remote sensing tools.