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The effect of aluminum doping on the structural, morphological and optical properties of Zn1-xAlxO (0 ≤ x ≥ 0.12) nanoparticles synthesized by sol–gel auto-combustion technique has been studied. All the x-ray diffraction patterns were single phase with a wurtzite crystal structure. The Scherrer, Williamson–Hall and Size–Strain plot (SSP) methods have been adopted to estimate the crystallite size, lattice stress, lattice micro-strain, and energy density using x-ray peak profile analysis. The crystallite size decreased, and the lattice strain, lattice stress, and energy density increased for Zn1-xAlxO (0 ≤ x ≥ 0.12) nanoparticles. The crystallite sizes obtained from the SSP method are highly intercorrelated with the morphology of aluminum-doped ZnO nanoparticles examined by field-emission scanning electron microscopy. The optical bandgap decreased with increasing the aluminum concentration in the ZnO nanoparticles, which correlated with the Urbach energy (Eu). The Eu values of aluminum-doped ZnO nanoparticles exhibited higher values than those of ZnO nanoparticles, which might be associated with the localized states originating from the contribution of defects and structural disorder. Photoluminescence results indicated the presence of defects in Zn1-xAlxO (0 ≤ x ≥ 0.12) nanoparticles, which were interlinked with zinc vacancies (VZn), zinc interstitials (Zin), neutral oxygen vacancies (VO), and oxygen interstitials (OI). [ABSTRACT FROM AUTHOR]

Vanadium pentoxide (V2O5) nanoparticles exhibit diverse properties and have been studied for a wide range of applications, including energy storage, catalysis, environmental remediation, and material enhancement. In this work, we have reported the synthesis of vanadium pentaoxide (V2O5) nanoparticles using hydrothermal method. Ammonium metavanadate (NH4VO3) was used as a source of vanadium. These syntheses were carried out at four different concentrations of vanadium source. The hydrothermal reaction was conducted at a temperature of 180 °C for a duration of 24 hours, followed by an additional 24 hours period of natural cooling. Four samples were annealed in air using a muffle furnace at 500 °C for five hours. The x-ray diffraction technique was used to study the structural aspects. A comparative analysis of the microstructure was conducted utilizing the Scherrer method, the Williamson–Hall method and its various models, size-strain analysis, and the Halder–Wagner method. The crystallite size and microstrain were determined using these distinct methods, revealing a systematic correlation between the crystallite size and microstrain obtained through the different techniques. [ABSTRACT FROM AUTHOR]

In this work, cadmium doped cobalt nickel ferrites were fabricated via co-precipitation method by using high purity chlorides as precursors and ammonia as precipitate. XRD measurements of synthesized Co0.6Ni0.4-xCdxFe2O4 ferrite samples revealed that the formation of mono phase cubic spinel structure ferrite nanoparticles. The volume of unit cell, crystallite size, lattice constant, bond length, hopping length, ionic radii and microstrain were directly affected by the inclusion of Cd2+ content in Co-Ni ferrite. The crystallite size (Dxrd) of prepared ferrite samples was obtained in between 14.52 and 16.92 nm. FTIR spectra showed two main absorption bands in the frequency range of 400–600 cm−1 arising due to stretching vibrations of tetrahedral (A) and octahedral (B) sites respectively. SEM analysis showed agglomerated morphology of ferrite nanoparticles with grain size decreased from 0.85 to 0.21 μm. Raman spectroscopy confirmed that, on addition of Cd2+content, Raman band was shifted towards higher wave number side. The crystallite development in Cd doped Co-Ni ferrites was explored by X-ray peak broadening methods such as Scherer’s formula, Size-Strain plot and Williamson hall methods. XRD analysis confirmed, the crystallite size and microstrain of Co0.6Ni0.4-xCdxFe2O4 ferrites were obtained from various methods, are highly inter correlated. Saturation magnetization (Ms) was decreased from 29.92 to 23.40 emu/gm with increase of Cd doping. The coercivity was reduced from 1113 to 708 Oe with Cd concentration. This is due to the magnetic anisotropy constant of Ni2+ ion is higher than that of the Cd2+ ion.

Si nanoparticles have been synthesized from rice husk. Adding KBr during the reduction of the magnesiothermic method in the synthesis of Si nanoparticles is effective as a scavenger agent. X-ray diffraction (XRD) study confirms the crystalline nature of the Si nanoparticles with a cubic silicon lattice structure, and scanning electron microscopy (SEM) analysis indicates the spherical morphology of the prepared nanoparticles, having an average size of approximately 27.77 nm. Scherrer, Williamson-hall, size-strain plot, and Halder-Wagner method have been used to investigate the particle size and the intrinsic strain from the XRD peak broadening analysis. Further, in the williamson-hall method, different models have been considered to determine physical and microstructural parameters such as strain, stress, and energy density. The average particle size distribution, calculated from several XRD and SEM, indicates that the average particle size is between 24.58 nm and 28.81 nm. The Si nanoparticles were also tested for electrical conductivity. The Si nanoparticles have an electrical conductivity of 2599.39 µS/cm and a resistance of 3.84 Ω at 1 V, indicating that Si nanoparticles are very good as material active electrode on a secondary cell battery.

In this study, the effect of the annealing temperature on the material properties and the structural properties of cuprous oxide was studied in order to investigate how the annealing temperature affects the material properties, and the temperature varied between 200℃, 300℃, 400℃ and 500 ℃ and was unannealed. The physical properties of the cuprous oxide were measured by X-ray diffraction (XRD). The XRD patterns showed that the Cu2O nanoparticles were highly pure, crystalline, and nano-sized. From the XRD results, we found the pure cuprite (Cu2O) phase. The values of crystal size were discovered and calculated by the Halder-Wagner and Size-Strain Plot (SSP) methods, respectively. The crystallite size increased as the annealing temperature increased. As a result, it was discovered that annealing temperature has a significant impact on structural and morphological aspects. In order to calculate physical and microstructural parameters such as internal strain, dislocation density, surface area, and consequently the number of unit cells, the sample was taken into consideration.

The structural properties of the CuO nanopowder oxide prepared reflux technique without any templates or surfactant, using copper nitrate hydrate (Cu(NO)3 3H2O) in deionized water with aqueous ammonia solution are reported. The Xrd analysis data and processing in origin pro program used to get FWHM and integral width to study the effect of different synthesis times was studied on the structural properties. It was found that values of crystal sizes are 17.274nm, 17.746nm, and 18.560nm, the size of nanoparticles is determined by Halder-Wagner, and 15.796 nm, 15.851nm, and 16.52nm, were calculated by Size-Strain Plot (SSP) method. The Sample was considered to determine physical and microstructural parameters such as internal strain, dislocations density, surface area, and the number of unit cells and then to compare the results.

Samples of CoFe1.5Ni0.5O4 were synthesized using the solid-state reaction method. As depicted from XRD plots, peak intensities increases as the sintering temperature goes from 1200 to 1300 °C signifying that the crystallinity has improved. Both the samples possess a spinel structure with space group Fd-3 m. The Rietveld refinement of the samples was done using Full-Prof software to calculate the cationic distribution and other structural parameters. The cation distribution for CoFe1.5Ni0.5O4 sintered at 1200 and 1300 °C were found to be (Co0.25Fe0.75) [Co0.75Fe1.23Ni0.03]O4 and (Co0.25Fe0.75) [Co0.76Fe1.21Ni0.03]O4 respectively. Also the value of lattice constants for the sample sintered at 1300 °C was found to be 8.355 Å which is greater than the lattice constant (8.342 Å) of the sample sintered at 1200 °C. The temperature-dependent dielectric characteristics of the samples were investigated in this work. This study revealed that as the sintering temperature rises, έ and tan δ decrease. Magnetic properties such as coercivity, remanence and saturation magnetizations were reported to decrease as the sintering temperature increased. The respective values of coercivity (Hc), remanence (Mr) and saturation magnetization (Ms) were 87.06 and 71.85 Oe, 9.61 and 7.98 and 63.90 and 56.90 emu/g for the samples sintered at 1200 and 1300 °C. Using low dielectric constant materials, low heat dissipation and parasitic capacitance are obtained, allowing these materials to be utilized in faster switching speeds in devices. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanoparticles were synthesised by the modified sol–gel method at different calcination temperatures. Samples were characterized using X-ray diffraction (XRD), high-resolution transmission microscopy, scanning electron microscopy, energy dispersive X-ray analysis (EDAX), Fourier transform infrared (FTIR) spectroscopy, Brunauer, Emmett and Teller surface area analyzer (BET) and diffuse reflectance spectroscopy (DRS). Phase transformation of TiO2 nanoparticles from anatase to rutile phase with an increase in calcination temperature from 573 to 1173 K was observed from XRD analysis. Detailed structural analysis using size–strain plot and Halder–Wagner method was done for all samples. The formation of TiO2 nanoparticles was confirmed from FTIR and EDAX spectra. The TEM image of the sample calcined at 673 K showed non-spherical shaped particles having particle sizes 13.16 ± 3.35 nm. The bandgap energy calculated from DRS decreases with an increase in calcination temperature, which supports phase transformation observed in XRD analysis. The photocatalytic degradation efficiency was evaluated by monitoring the degradation of Congo red (CR) azo dye under UV light and natural sunlight. The degradation of CR dye was confirmed by analysing the FTIR spectrum of the degraded sample. The sample calcined at 673 K, in the pure anatase phase, exhibited the highest photocatalytic activity. [ABSTRACT FROM AUTHOR]

Here, sol–gel derived Fe–TiO2 anatase nanoparticles with varying concentrations of Ti(1–x)FexO2 (x = 0%, 1%, 5%, 10%) were prepared. The structural, morphological, and optical properties of prepared samples were studied. X‐ray diffraction (XRD) patterns show the formation of pure anatase phase. The mean crystallite size of Fe–TiO2 decreases with increase in the concentration of Fe. Fourier transform infrared spectroscopy (FTIR) spectra confirmed the presence of Ti–O vibrational band for all the samples. In Raman spectrum, peak broadening and red shifting linked with Eg ∼144 cm–1 divulge the Fe substitution at Ti sites into host lattice structure. Photoluminescence (PL) spectra verified nine peaks related to near band‐edge emission and various defect states. The UV–vis diffuse reflectance spectra represent redshift and reduction in the bandgap energy. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) investigations show that the size of the grains decreases with increase in Fe doping concentration. The study shows that Fe‐doped TiO2 anatase phase nanoparticles are suitable for photocatalytic activity and solar cell applications. [ABSTRACT FROM AUTHOR]

Undoped and Ce-doped CuO nanoparticles were synthesized by an energy-efficient sol–gel combustion method with citric acid as fuel. The as-synthesized samples were further annealed at 600 and 800 °C. The X-ray diffraction results revealed that the synthesized samples exhibit a monoclinic structure with the impurity phase (CeO2) at 600 and 800 °C. Using Debye–Scherrer, Williamson–Hall (WH), size-strain plot and Halder–Wagner methods, it is found that the crystallite size of the CuO nanoparticles increased with annealing temperature and decreased with Ce dopants. Moreover, the crystallite size and strain are found to be highly inter-correlated. Furthermore, the contribution of elastic properties such as strain, stress, Young's modulus and energy density has been thoroughly studied by a modified form of the Williamson–Hall method. The uniform deformation model, uniform stress deformation model and uniform deformation energy density model (UDEDM) have been considered from the WH method. It is found that the change in crystallite size is highly influenced by the strain, stress and energy density. Williamson–Hall's UDEDM is the most appropriate approach to estimate the crystallite size. However, the size-strain plot is highly preferable to estimate the microstrain since the WH method gives a higher strain value. [ABSTRACT FROM AUTHOR]

Ferric nitrate Fe(NO3)3 ⋅9H2O as a precursor and Ethylene Glycol as a solvent were used to prepare iron oxide nanoparticle via sol gel method. X-ray diffraction (XRD) study of IONPs at different calcination temperatures to determine the size of the crystallite was performed using various methods of calculation: Scherrer, Williamson-Hall (W-H), Halder-Wagner (H-W) and Size-Strain plot (SSP). The Scherrer and H-W methods reveal that the crystallite size decreases in the presence of a single phase (γ-Fe2O3) at lower temperature, as the contribution of other-phase (α-Fe2O3) increases size varies, but again decreases as the material converts to a single phase, while with temperature, the Size-Strain Plot and Halder-Wagner Method show increased crystallite size. FE-SEM and HR-TEM investigations confirm that the synthesized IONPs are spherical. EDX spectra and FTIR analyses have shown that synthesized particles are pure iron oxide nanoparticles. The average particle size calculated using different models below than 20 nm. [ABSTRACT FROM AUTHOR]

MFe 2 O 4 (M = Co, Fe, Mn, Zn) nanoparticles were successfully synthesized by coprecipitation. Analyzing the X-ray diffraction by the Rietveld method confirmed the spinel ferrite structure of the samples. Rietveld refinement results show that Co, Mn and Zn occupy both the tetrahedral and octahedral sites. Variation in elastic parameters was determined by Fourier transform infrared spectroscopy, and cation distribution was deduced from X-ray diffraction. X-ray diffraction peak expansion was analyzed by employing a variety of calculating methods such as modified Scherrer, Williamson–Hall, size–strain, and Halder–Wagner to determine the crystallite size and elastic parameters of the cubic-structured MFe 2 O 4 nanoparticles, including intrinsic strain, stress, and energy density. Comparison of the results obtained from these different methods revealed that they are ideally suited to each other. Moreover, the transmission electron microscopy image confirmed that the average size of MFe 2 O 4 (M = Co, Fe, Mn, Zn) nanoparticles ranges from 10 to 14 nm, consistent with the dimensions obtained from the preceding methods. [Display omitted] • Coprecipitation technique was utilized to synthesize MFe 2 O 4 ferrite nanopowders. • Elastic properties have been investigated based to the cation distribution and FTIR spectrum. • Different models were engaged to estimate crystallite size. • Calculated average particle size from SSP and H-W method are found to match very well with that obtained from TEM. [ABSTRACT FROM AUTHOR]

Here, 3-marcaptopropionic acid capped CdTe and Ag doped CdTe (Ag/CdTe) nanocrystals have been prepared by chemical method for the study of the effect of silver doping on the size and elastic properties, especially the intrinsic strain from the x-ray diffraction (XRD) study. Transmission electron microscope images show both the CdTe and Ag/CdTe are spherical in shape and confirms that with the doping of silver, the average size slightly decreases from 7 to 6 nm. Again, selected area electron diffraction pattern shows that both the nanocrystals are crystalline in nature, which has further been confirmed from XRD pattern. From the XRD peak broadening study, different elastic properties have been calculated for both CdTe and Ag/CdTe nanocrystals by using different model of Williamson–Hall (W–H) plot and size–stain plot method. From these studies, it has been found that average size decreases by almost 15% after doping, whereas intrinsic strain with other elastic properties increases by almost 70% after doping of silver. Thus, silver doping has significant effect on the size and elastic properties of CdTe nanocrystals. [ABSTRACT FROM AUTHOR]

Semiconducting cuprous iodide (CuI) nanocrystals have been synthesized by the one‐pot sonochemical method at room temperature. The synthesis was performed in aqueous medium using ascorbic acid, polyvinyl pyrrolidone, p‐toluene sulfonic acid and docusate sodium as surfactants. X‐ray diffraction (XRD) study of resulting material reveals the crystalline nature, cubic zinc blende lattice structure and γ phase of CuI nanocrystals. Scherrer method, Williamson‐Hall plot and Size‐Strain plot method have been used to investigate the particle size and intrinsic strain values from the XRD analysis. Field emission scanning electron microscopy (FESEM) revealed the morphology and different shapes (truncated tetrahedron, irregular, hexagonal & clustered) of CuI nanocrystals synthesized using different surfactants. In the PL spectrum of γ‐CuI nanoparticles strong near band‐edge emission was observed at about 423 nm. A slight red‐shift in near band edge emission was observed due to the presence of surfactants. Enhanced electrical conductivity values (1.96 S/cm–9.19 S/cm) were obtained due to the presence of surfactants for γ‐CuI nanocrystals. These properties of CuI nanocrystals makes them a suitable material for the design and development of optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this work, jagged spherical CdS nanocrystals have been synthesized by chemical method to study their elastic properties. The synthesized CdS nanocrystal has been characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The transmission electron microscope images show that the average size of the nanocrystal is 100 nm approximately. X-ray diffraction (XRD) study confirms that the CdS nanocrystals are in cubic zinc blende structure. The size calculated from the XRD is consistent with the average size obtained from the TEM analysis. The XRD data have been analyzed to study the elastic properties of the jagged spherical CdS nanocrystals, such as intrinsic strain, stress and energy density, using WilliamsonHall plot method. Williamson-Hall method and size-strain plot (SSP) have been used to study the individual effect of crystalline size and lattice strain on the peak broadening of the jagged spherical CdS nanocrystals. Size-strain plot (SSP) and root mean square (RMS) strain further confirm the results obtained from W-H plots. [ABSTRACT FROM AUTHOR]

Zinc-doped manganese spinel ferrite nanocrystals with chemical formula Mn 0.75 Zn 0.25 Fe 2 O 4 were synthesized by the chemical co-precipitation method. The structural properties of the synthesized nanoparticles were studied by X-ray diffraction analysis (XRD), whereas morphological analysis was performed by high-resolution transmission electron microscopy (HR-TEM) and scanning electron microscopy. The XRD study confirmed the formation of single-phase spinel face-centered cubic nanocrystals with an average size of approximately 19 nm. HR-TEM analysis gave an average particle size of approximately 15 nm, with the nanocrystals being almost spherical. The selected-area electron diffraction pattern obtained in the HR-TEM study clearly indicated the polycrystalline nature of the nanocrystals. The Fourier transform infrared spectrum confirmed the formation of a pure spinel ferrite structure. Williamson-Hall plot analysis, using the XRD data, was used to obtain information on the different elastic properties, such as residual strain, stress, and energy density, considering the uniform deformation model, the uniform stress deformation model, and the uniform deformation energy density model. The results were compared with the results obtained by the size-strain plot method. The XRD data were used to determine the lattice parameter, which was found to be 0.81 nm. With use of the calculated lattice parameter, the ionic radii, bond lengths of the tetrahedral and octahedral sites, and hopping lengths of the spinel ferrite nanocrystals were calculated. Finally, a magnetic study using a vibrating-sample magnetometer showed that the nanocrystal sample is superparamagnetic. Size-strain plot for the determination of the size and strain value for the prepared zinc doped manganese spinel ferrite using the XRD data. Image 1 • Mn 0.75 Zn 0.25 Fe 2 O 4 nanoparticles were prepared by the co-precipitation method. • The high-resolution transmission electron microscopy images show that the average size is approximately 15 nm. • Different elastic parameters were studied by a Williamson-Hall plot using X-ray diffraction analysis. • The ionic radii, bond lengths, and hoping lengths were calculated.. [ABSTRACT FROM AUTHOR]

In this work , cadmium doped cobalt nickel ferrites were fabricated via co-precipitation method by using high purity chlorides as precursors and ammonia as precipitate. XRD measurements of synthesized Co 0.6 Ni 0.4-x Cd x Fe 2 O 4 ferrite samples revealed that the formation of mono phase cubic spinel structure ferrite nanoparticles. The volume of unit cell, crystallite size, lattice constant, bond length, hopping length, ionic radii and microstrain were directly affected by the inclusion of Cd2+ content in Co-Ni ferrite. The crystallite size (D xrd) of prepared ferrite samples was obtained in between 14.52 and 16.92 nm. FTIR spectra showed two main absorption bands in the frequency range of 400–600 cm−1 arising due to stretching vibrations of tetrahedral (A) and octahedral (B) sites respectively. SEM analysis showed agglomerated morphology of ferrite nanoparticles with grain size decreased from 0.85 to 0.21 μm. Raman spectroscopy confirmed that, on addition of Cd2+content, Raman band was shifted towards higher wave number side. The crystallite development in Cd doped Co-Ni ferrites was explored by X-ray peak broadening methods such as Scherer's formula, Size-Strain plot and Williamson hall methods. XRD analysis confirmed, the crystallite size and microstrain of Co 0.6 Ni 0.4-x Cd x Fe 2 O 4 ferrites were obtained from various methods, are highly inter correlated. Saturation magnetization (M s) was decreased from 29.92 to 23.40 emu/gm with increase of Cd doping. The coercivity was reduced from 1113 to 708 Oe with Cd concentration. This is due to the magnetic anisotropy constant of Ni2+ ion is higher than that of the Cd2+ ion. [ABSTRACT FROM AUTHOR]

Nanostructured copper particles are synthesized by Garcinia mangostana leaf extract as reducing agent with copper nitrate. X-ray diffraction study confirms the formation of nanocrystalline cubic phase of copper nanoparticles. The micro-structural properties such as grain size, strain, dislocation density and particle size are examined. The lattice constant is calculated using Nelson–Riley function. Physical parameters like lattice constants, stress, strain, dislocation density and size are calculated. Differential thermal analysis (DTA) and thermo gravimetric (TGA) have confirmed that nanoparticles have phase purity and weight loss percentage is 3.328%. The particle size calculated from XRD is 26.51 nm which is in good agreement with the results of W–H plot, SSP methods and particle analyser. The morphology of prepared copper nanoparticles is characterized by scanning electron microscope (SEM) and TEM. These biologically synthesized nanoparticles are highly antibacterial against Escherichia coli and Staphylococcus aureus.

Nanostructured SnS 1−x Te x (X = 0.0, 0.020, 0.027, 0.032, 0.036) thin films were deposited on fluorine doped tin oxide (FTO) substrates by an electrochemical route. The electrolyte contained SnCl 2 (2 mM), Na 2 S 2 O 3 (16 mM) and various amounts of TeO 2 solution (4 mM) as a dopant. The electrochemical deposition was done under the same condition for all samples. The deposition potential ( E ), deposition time ( t ), pH and electrolyte temperature ( T ) were −1 V, 30 min, 2.1 and 60 °C, respectively. Only the concentration of Te-dopant was changed to prepare nanostructured SnS 1−x Te x thin films. The synthesized SnS 1−x Te x samples were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and room temperature photoluminescence (PL). The XRD pattern revealed that the nanostructured SnS 1−x Te x thin films were crystalline with an orthorhombic phase. The TEM images presented that the single crystals of SnS 1−x Te x nanostructures were almost spherical in shape. By X-ray peak broadening, the crystalline development in the SnS 1−x Te x nanostructures was studied. In order to check the individual contributions of crystalline sizes and lattice strains on the peak broadening of the SnS 1−x Te x nanostructures, the Williamson-Hall (W-H) analysis and size-strain plot (SSP) method were used. The physical parameters such as strain and stress values were calculated exactly for all the reflection peaks of XRD related to the SnS 1−x Te x nanostructures lying in the range of 20°–60°, from the W-H plot supposing a uniform deformation model (UDM) and by the SSP method. A relationship describing the particle size of SnS 1−x Te x samples was observed among the obtained results from the TEM, W-H analysis and SSP method. The PL results exhibited a good agreement with XRD pattern. [ABSTRACT FROM AUTHOR]

Nanostructured copper particles are synthesized by Garcinia mangostana leaf extract as reducing agent with copper nitrate. X-ray diffraction study confirms the formation of nanocrystalline cubic phase of copper nanoparticles. The micro-structural properties such as grain size, strain, dislocation density and particle size are examined. The lattice constant is calculated using Nelson–Riley function. Physical parameters like lattice constants, stress, strain, dislocation density and size are calculated. Differential thermal analysis (DTA) and thermo gravimetric (TGA) have confirmed that nanoparticles have phase purity and weight loss percentage is 3.328%. The particle size calculated from XRD is 26.51 nm which is in good agreement with the results of W–H plot, SSP methods and particle analyser. The morphology of prepared copper nanoparticles is characterized by scanning electron microscope (SEM) and TEM. These biologically synthesized nanoparticles are highly antibacterial against Escherichia coli and Staphylococcus aureus . [ABSTRACT FROM AUTHOR]

The equation for the size strain plot methods reported by A. Khorsand Zak et al. (Solid State Sci. 13 (2011), 251) [1] does not follow the dimensional homogeneity, consequently leading to an inaccurate estimation of the crystallite size and strain values of the materials under investigation and the dimensions of the obtained parameters. We also perceived an error in the values of crystallite size and strain reported by the authors using the size-strain plot method. We will discuss the importance of dimensional analysis and its repercussions on the estimated values and the units of parameters. [Display omitted] [ABSTRACT FROM AUTHOR]

RuO 2 nanoparticles (RuO 2 NPs) have been successfully synthesized by the hydrothermal method. Structure and the particle size have been determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM). UV–Vis spectra reveal that the optical band gap of RuO 2 nanoparticles is red shifted from 3.95 to 3.55 eV. BET measurements show a high specific surface area (SSA) of 118–133 m 2 /g and pore diameter (10–25 nm) has been estimated by Barret–Joyner–Halenda (BJH) method. The crystallite size and lattice strain in the samples have been investigated by Williamson–Hall (W–H) analysis assuming uniform deformation, deformation stress and deformation energy density, and the size–strain plot method. All other relevant physical parameters including stress, strain and energy density have been calculated. The average crystallite size and the lattice strain evaluated from XRD measurements are in good agreement with the results of TEM. [ABSTRACT FROM AUTHOR]

Nanostructured cadmium zinc sulphide films have been deposited onto cleaned glass substrates by chemical bath deposition method at room temperature using polyvinyl alcohol as capping agent. X-ray diffraction analysis confirms the formation of cubic-phase cadmium zinc sulphide films. Crystallite size obtained from the calculation of Scherrer's formula and Williamson-Hall plot as well as size-strain plot is found to decrease with the increase in zinc concentration. The films have very high dislocation density of the order of 10 m, whereas the strain is of the order of 10. Scanning electron microscopic image reveals that the particles are agglomerated to form nanoclusters and energy-dispersive X-ray analysis confirms that films are composed of cadmium, zinc and sulphur. High-resolution transmission electron microscopic image reveals that the shape of the particles is nearly spherical, uniformly distributed. Selected-area electron diffraction pattern supports the formation of cubic phase of the film. Optical absorption peaks of the films shift towards lower wavelength side and their optical band gap increases with the increase in zinc concentration. The increase in zinc concentration enhances the photoluminescence emission intensity, whose emission is in the green region of visible spectrum. [ABSTRACT FROM AUTHOR]

Nanostructured cadmium sulphide thin films have been synthesized onto suitably cleaned glass substrates by simple chemical bath deposition method at room temperature using polyvinyl alcohol as capping agent. X-ray diffraction study confirms the formation of nanocrystalline cubic phase of cadmium sulphide in the films. Various physical parameters such as lattice constant, stress, strain, dislocation density, etc. have been calculated and are found to be affected by the molarity of the solution. The ultra-high resolution transmission electron microscopic study shows that the shape of the particles is nearly spherical and the average particle size agrees well with the result obtained from X-ray diffraction study. Selected area electron diffraction patterns have also supported the formation of cubic phase of cadmium sulphide. The surface texture of the prepared films investigated using atomic force microscopy confirms the formation of nanocluster of high density cadmium sulphide nanoparticles. The surface is slightly non-smooth with uniform crack-free and densely packed microstructure. [ABSTRACT FROM AUTHOR]

Abstract: Undoped and Mg-doped ZnO nanoparticles (NPs) (Zn1−x Mg x O, x=0.01, 0.03, and 0.05) were grown by the sol–gel method. X-ray results showed that the products were crystalline with a hexagonal wurtzite phase. Microscopy studies revealed that the undoped ZnO NPs and Zn1−x Mg x O NPs had nearly spherical and hexagonal shapes. The size–strain plot (SSP) method was used to study the individual contributions of crystallite sizes and lattice strain on the peak broadening of the undoped and Mg-doped ZnO NPs. Some physical parameters such as strain, stress, and energy-density values were calculated for all reflection peaks of the XRD corresponding to the wurtzite hexagonal phase of ZnO in the 20–100° range from the SSP results. The effect of doping on the band-gap was also investigated by a photoluminescence (PL) spectrometer. The PL results showed that Mg2+ is a good dopant to control band gap of the ZnO properties. [Copyright &y& Elsevier]

In this study, polypyrrole cuprous iodide (PPy-CuI) hybrid nanocomposites were synthesized in an aqueous medium via an in-situ chemical oxidation route with ammonium persulphate as an oxidizing agent to report the microstructural, morphological, and electrical properties of as-synthesized specimens. By using an in-situ oxidative polymerization method, sonochemically synthesized γ-CuI nanocrystals were mixed with a PPy matrix in varying weight percentages (10–40 ​%). The purity, crystallinity and structure of hybrid nanocomposites were determined using X-ray diffractometry. The average crystallite size of hybrid nanocomposites was calculated using the Debye-Scherrer, Williamson-Hall and Size-Strain plot methods. All specimens' intrinsic strain was estimated using the Williamson-Hall plot and the Size-Strain plot methods. The field emission scanning microscopy revealed that the surface morphology changed from granular to overgrown clusters as the weight percent of CuI nanocrystals is increased from 10 to 40 ​% in PPy-CuI hybrid nanocomposites. The Fourier transform infrared spectroscopy indicates the formation of PPy and successful insertion of γ-CuI nanocrystals into the PPy matrix. The room temperature dc electrical conductivity is found to decrease from 6.3 ​× ​10−2 Scm−1 to 1.70 ​× ​10−3Scm−1as the wt% of γ-CuI nanocrystals increases from 10 to 40 ​% in hybrid nanocomposites. Furthermore, the increasing trend of dc conductivity with temperature is due to all samples' semiconducting nature. In the temperature range of 200–300 ​K, the measured experimental data followed the Arrhenius and Mott's 3d variable range hopping (VRH) model. The values of average activation energy, average hopping energy, density of states at Fermi level, average hopping distance and Mott's characteristic temperature of PPy-CuI (40 ​%) hybrid nanocomposites at 300 ​K were estimated to be ~60 ​meV, ~29 ​meV, 6.36 ​× ​1022 ​cm−3eV−1, 5.06 ​Å and 1901 K, respectively. [Display omitted] • PPy-CuI hybrid nanocomposites in different wt% were synthesized by a simple chemical technique at low temperature. • A comparative study on size and strain of PPy-CuI HNCs was carried out using Scherrer formula, WH plot and SS plot methods. • The room temperature conductivity was found to decrease with increase in CuI wt% in PPy. • Electrical conductivity of PPy-CuI HNCs was found to increase with increasing temperature in the range of 200–300 ​K. [ABSTRACT FROM AUTHOR]

Cobalt doped Zinc Oxide (Zn 1-x Co x O) (x = 0.03) nanoparticles have been synthesized by chemical co-precipitation method at room temperature and characterized by X-ray diffraction (XRD) study. The XRD pattern indicates that Co doped ZnO NPs are with hexagonal wurtzite geometry and diffraction peaks get shifted to higher angles which is the characteristic influence of dopant Co that has an ionic radius smaller than the host cation. The true values of lattice constants have been calculated using Nelson–Riley Function. Crystallite size calculated using Scherrer formula has been compared with that estimated by uniform deformation (UDM), uniform stress deformation (USDM) and uniform deformation energy density (UDEDM) models of Williamson – Hall method, and also by size-strain plot (SSP) method. The lattice strain has also been calculated. The surface morphology and elemental analysis of the product have been characterized by field emission scanning electron microscopy (FESEM) and energy dispersive (EDAX) spectra. [ABSTRACT FROM AUTHOR]

• Undoped, In, Cu and Al-doped SnO 2 thin films are deposited by spray pyrolysis. • Structural properties of the films are investigated by X-ray diffraction method. • Crystallite size is calculated using Williamson-Hall and Size-Strain Plot methods. • Physical parameters including strain, stress and energy density are also obtained. • Electrical properties are determined and bridge to structural properties is built. The undoped, Cu, Al and In (2 at. %) doped SnO 2 thin films are deposited on the glass substrate by spray pyrolysis. The effect of Cu, Al and In doping on the structural properties of SnO 2 films are investigated by X-ray diffraction (XRD) method. All structural parameters including crystallite size, lattice strain, stress and energy density values are determined from three different models based on Williamson-Hall (W-H) and size-strain plot (SSP) methods. The obtained results reveal that strain values are almost the same but crystallite size, stress and energy density values of the films are greatly affected by dopant atoms. Surface morphologies are analyzed using atomic force microscopy (AFM) measurements. The electrical properties are investigated by Hall effect measurements at room temperature. The number of valance electrons of dopant atoms are less than Sn, as a result the decrement in electrical conductivity and the compensation of n-type conductivity are observed. [ABSTRACT FROM AUTHOR]