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This article demonstrates the effect of substrate temperature on the pulsed-laser deposition of cadmium sulfide nanoparticles (CdS NPs). Synthesis of CdS NPs on silicon substrates was realized at a temperature range of 150–550 °C. The XRD patterns confirm that CdS NPs showed a wurtzite-hexagonal phase with crystallite size changes between 15 and 24 nm. Also, the SEM images indicate that the temperature is a crucial parameter could determine the morphology of the nanoparticles. Hence, some films exhibited aggregation and cracks causing a significant degradation in the crystalline quality. The results identify that the best quality CdS NPs correspond to an optimal temperature of 450 °C at which the nano-heterostructures could be useful for nanoelectronic applications.

We discovered Elinvar effect in a severely cold worked Ti-50.8(at%)Ni thin belt that showed a modulus variation of less than 0.54GPa(∼1%) over a wide temperature range (−50 to 100 °C). Microstructural analysis showed an unraveled amorphous matrix dotted with nanosized crystallites, which demonstrated that the softening of the nanodomains in the retained nanosized crystallites and hardening of the amorphous matrix during cooling over wide temperature range can trigger the Elinvar effect.

A nanostructured mixture of two SmNbO4 polymorphs, one monoclinic and other tetragonal, was synthesized by mechanical alloying. It was the first time that the tetragonal structure was synthesized at low temperature. Both polymorphs are stable in high temperatures. A single monoclinic phase with nanometric crystallites was obtained after annealing at 1000 °C.

The paper presents a molecular dynamics study on the propagation of an intrinsic stacking fault in a copper crystallite under tension. The study shows that the defect moves via the formation of four successive structural configurations in two adjacent regions at its front. Local decrease of atomic volume gives rise to the formation of intermediate structural configuration with bcc symmetry in one of the regions, while an increase of volume in other region leads to the formation of configuration with 13 nearest neighbors. Such intermediate configurations occur with an increase in the potential energy. The atomic volume and the potential energy take their initial values during final rearrangements which move the stacking fault on one elementary step.

In this work, p-type Bi0.5Sb1.5Te3 polycrystalline materials were fabricated by a modified melting method without vacuum protection, and the effects of the air isolation from the capping agents on the microstructure, phase purity, and thermoelectric properties were systematically investigated. Results show that capping agents could effectively prevent elementary materials from oxidation and evaporation. A maximal figure of merit of approximately 1.2 is obtained at 373 K for the sample loaded with 3.2 g of capping agents. With the help of capping agents, the vacuum condition is no longer a necessity for the fabrication of p-type bismuth telluride systems, which would be beneficial for the large-scale processing from the point of view of industrial production.

Pyrite is part of the tailings from coal mining and presents a great valorization potential technological, economic and environmental in the production of nanoparticles. In this work, pyrite from coal mining was subjected to high-energy milling and the particle size reduction, electrical and optical properties were evaluated. With the milling parameters used, the apparent size of the crystallites was reduced from 34.7 nm to 23.8 nm, resulting in highly unstable particles and charge carriers with low mobility. Due to this instability, submicron particles were observed, in the range of 300–500 nm, with a hydrodynamic diameter of 1257 ± 36 nm. The processed pyrite showed good visible light absorption and an indirect band gap of 1.51 eV.

Room temperature elastocaloric effect as well as the effects of strain rate and loading stress have been studied in polycrystalline Ni51Mn34In8Sn7. The increase of strain rate reduces plastic deformation and lattice invariant strain, thus improving the superelasticity. Higher strain rate and stress facilitate the stress-induced structural transition and adiabatic environment, and so the temperature change (ΔT) increases at a rate of 1.77 K (1% s−1)−1 and 1.78 K (102 MPa)−1. A large ΔT of 4.2 K is obtained by optimizing the strain rate and loading stress, which is comparable to or even larger than those of many NiMn-based alloys at room temperature. This result suggests polycrystalline Ni51Mn34In8Sn7 as a desirable material for room temperature elastocaloric refrigeration.

(In1−xFex)2O3 nanoparticles were prepared by freeze-drying an aqueous solution of indium acetate and iron acetate followed by heat treatment. The samples were characterized by high-resolution X-ray diffraction, transmission electron microscopy, Fourier transform infrared and UV–Vis diffuse reflectance spectroscopy. The x ≤ 0.12 nanoparticles were shown to be monophasic and crystallized with the bixbyite structure. Iron doping the In2O3 semiconductor reduced the lattice parameter, crystallite size, and optical bandgap.

Tuning optical properties for narrow band gap semiconductors is attractive and meaningful for infrared optical and optoelectronic devices. Here, we demonstrate the impacts of O+ beam on morphological, structural and optical properties of polycrystalline PbSe thin films using an L9 (33) orthogonal experimental design. Three types of specific surface microstructures were induced by ion beam. Morphological evolutions were revealed to be manipulated by beam configurations. Tunable optical band gap and enhanced absorbance were also induced by ion beam modifications. The structural properties and the Urbach energy as low as ∼2 meV both suggest a well-ordered microstructure of this material with high crystallinity.

In this work, heterojunctioned TiO2/ZrO2 – zirconium titanate phases have been designed through a precursor derived approach. The X-ray powder diffractograms (XRD) revealed that the synthesized powder contained phase pure rutile, a mixture of rutile/zirconia and zirconium titanate or monoclinic zirconia (m-ZrO2) as we vary the amount of initial precursors. The scanning electron micrographs (SEM) and transmission electron micrographs (TEM) showed a decrease in crystallite size with increase in the amount of Zr to Ti precursor and formation of heterojunctions, respectively. An anomalous reduction in band gap was observed for 70T-30Z (2.54 eV) and 60T-40Z (2.71 eV) samples when compared to their parent oxides, TiO2 (2.86 eV) and ZrO2 (4.5 eV) and this could be attributed to the formation of heterojunctions between the two phases.

Benzene compounds generates a series of reducing substances under high temperature conditions and is capable of converting insulating polycrystalline C12A7 into a conductive material. Conductive C12A7:e− is prepared by placing the C12A7 insulation and benzene compounds together and calcining at 1100 °C for a period of time. At present, the conductivity of C12A7:e− prepared by this method can be as high as 8.71 S·cm−1, and the electron concentration can reach 1.68 × 1020 cm−3. Studies on the conductive mechanism of C12A7 show that all benzene ring-containing compounds enable to significantly improve its conductivity. Moreover, the process is similar to the industrial preparation methods of cement and ceramics, and does not need to be performed in a vacuum environment, which is considerably suitable for the large-scale industrial manufacture in the future.

Highly efficient CdTe absorber-based solar cells often require Cu-doping for lower resistivity and a suitable ohmic contact, but Cu migration degrades the performance and creates instability of device. Therefore to address these problems, there is a need to optimize CdTe single layer itself with another suitable doping element, so in this report, we have optimized the physical properties of Bi-doped CdTe thin films where the films were air annealed at the different temperatures. Structural analysis revealed the polycrystalline nature with (1 1 1) preferred reflection and maximum grain growth for films annealed at 300 °C as well as high optical absorbance and maximum conductivity are also observed for these films. The investigated findings show that films annealed at 300 °C have favorable properties and may be utilized in the fabrication of highly efficient solar cells.

We report on the THz generation and optical characterizations such as index of refraction, absorption coefficients of indigenously grown, potentially NLO active N-benzyl-2-methyl-4-nitroaniline (BNA) single crystals grown from four different solvents such as N, N dimethylformamide (DMF), Methanol (MeOH), Acetonitrile (ACN) and ACN: DMF (1:1) in an intentionally selected frequency range of 0.1–2.0 THz at room temperature (RT). The DMF was identified to be a promising candidate as it facilitated reduction in the inclusions. The powder Second Harmonic Generation (SHG) measurements performed on BNA polycrystalline samples revealed that their efficiencies were about 8.4 and 2.3 times higher than KDP and Urea samples respectively. The absorption coefficients and refractive indices made in this technologically important THz range using the BNA crystals grown from selected solvents exhibited, interestingly, solvent dependency.

Dye sensitized solar cells are promising class of photovoltaic cells with the capability of generating green energy at low production cost since no expensive equipment is required in their fabrication. Zinc oxide (ZnO) nanorods were synthesized by hydrothermal method and their performance as photoanodes in dye sensitized solar cells (DSSCs) with dye extracts from fruits of Phytolacca icosandra and Phyllanthus reticulatus as sensitizers was analyzed. Detailed structural and surface characterization of the ZnO nanorods were accomplished using X-ray diffraction (XRD) analysis and high resolution scanning electron microscopy (HRSEM). XRD results revealed that the synthesized ZnO material exhibited hexagonal crystal structure which was found to be highly stable and crystallite. The dye extracts were subjected to UV–Visible absorption spectroscopy and Fourier Transform Infrared (FTIR) analysis. The short-circuit photocurrent; the open-circuit photovoltage, and the power conversion efficiency of DSSC were measured using J-V measurement system.

Solid-state secondary batteries employing solid electrolytes provide the advantage to be potentially more stable than conventional batteries and hence are safer. At present, investigations of related ionic conductivities of solid ion conductors are attracting attention. In this work, we have prepared SmF3 with CaF2 doped materials. Different Sm1−xCaxF3−x compositions which are dependent on the stoichiometric ratio (0 ≤ x ≤ 0.15) had been obtained by planetary high-energy mechanochemical milling. Structural, morphology and ionic conductivities of the synthesized Sm1−xCaxF3−x electrolytes were examined. From X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM), it was revealed that Sm1−xCaxF3−x constitutes in a tysonite-type structure with a crystallite size of around 10–20 nm and an average particle size of 50 nm. At room temperature, the highest ionic conductivity was achieved for Sm0.95Ca0.05F2.95 of 2.8·10−5 S cm−1. The corresponding activation energy was extracted to be 0.40 eV. Finally, a proof-of-principle solid-state Fluoride Ion Battery (FIB) had been tested based on a CeF3/Sm0.95Ca0.05F2.95/Bi electrochemical system.

Titanium-doped Zinc oxide (Zn1−xTixO1+x; x = 0, 0.06, 0.09, 0.15) nanoparticles have been synthesized by sol-gel method at 80 °C and further annealed at 450 °C in ambient environment to study their structural and optical properties. The XRD data shows that the synthesized ZnO nanoparticle is polycrystalline in nature with average crystallite size of ∼6.3 ± 0.1 nm and highly oriented in (1 0 1). Titanium doping in ZnO indeed reduces crystallinity and average crystallite size which can be increased after annealing at 450 °C in ambient environment. Optical studies reveal that the value of optical band gap (Eg) for as-prepared Zn1−xTixO1+x samples increases with increasing the Ti more fraction, the value being 3.24, 3.28, 3.30, 4.06 eV, for x = 0, 0.06, 0.09, 0.15, respectively. The value of Eg is laid to lower value upon annealing at 450 °C in ambient environment. The defects like zinc interstitials and grain boundaries are controlled by Ti-dopant cations and annealing as confirmed by photoluminescence study. ITO/Zn1−xTixO1+x (x = 0.09)/PEDOT:PSS/P3HT:PCBM/LiF/Al solar cell device is demonstrated with higher power conversion efficiency (ɳ ∼ 2.09%) than its pristine device (ɳ ∼ 1.36%).

In this work, novel BCP (β-CPP, β-Ca2P2O7/β-TCP, β-Ca3(PO4)2) bioceramics have been synthesized by wet chemical precipitation using lime mud waste from cellulose industry as inexpensive sustainable CaCO3 precursor source. The synthesized BCP bioceramics have been characterized regarding to X-ray diffraction (XRD), Rietveld refinement, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The results indicated that the amounts of the phases β-CPP and β-TCP in the biphasic mixtures depend on the different HNO3 molar concentrations used in the synthesis. In addition, the BCP (β-CPP/β-TCP) powders exhibited average crystallite size in the range of 55.56 to 59.85 nm. Such novel BCP nanopowders produced by using CaCO3 from lime mud waste have high potential for biomedical applications.

The feasibility of incorporating high (M/M+Ca = 16 mol. %) and low (M/M+Ca = 4.76 mol. %) concentrations of Mg2+, Zn2+ and Sr2+, as divalent cations with interesting biological properties, into the structure of well-known bioceramic: hydroxyapatite (HA) was carefully assessed. An established hydrothermal synthesis method was employed for preparation of HA in whisker-like morphology. Consequently, the possibility of synthesizing HA whiskers (HAWs) with cationic substitutions and effects of the introduced ions on morphology, structure and composition of HA products were evaluated. Almost, all the cation-substituted preparations could maintain the apatite phase, while the decrease in crystallite size and crystallinity was obvious. Lattice parameters (a, c) of the hexagonal system of HA were also affected in accordance with the type and amount of substituting cation. Zn2+ and high amounts of Mg2+ dramatically inhibited formation of whisker-like apatite and promoted formation of a mixture of hexagonal prism-like and flaky bundles, or hexagonal and multifaceted morphologies, respectively. However, Sr2+ exhibited minimum inhibitory effect on HAWs formation. Therefore, Sr- and Mg-substituted (low concentration of Mg) HAWs could be prepared for their potential biomedical applications.

A Cu-10 vol% Y2O3 nanocomposite was successfully fabricated via a novel route, namely a multi-step ball milling and reduction process, using CuO and Y2O3 as raw materials. The copper matrix nanocomposite exhibited a high microhardness of HV209.6 (three times that of pure copper), high compressive 0.2% strength of 655 MPa (seven times that of pure copper), favourable ductility of 33.4% and good electrical conductivity of 53.8% IACS. The changes in phases and microstructure after different process steps were investigated. The result revealed that CuO particles were reduced nearly completely after the 2nd reduction process, and the crystallite size of copper remained in the nanoscale after the consolidation process. Furthermore, 10 vol% yttria nanoparticles were uniformly dispersed in the nanocrystalline copper matrix composite.

Iron oxide nanoparticles (NPs) were synthesized at room temperature, using a method based on a chemical reaction of iron filings, white vinegar, hydrogen peroxide, and ammonium hydroxide, in the presence of an external magnetic field (EXMF) of 1200 G. X-ray diffraction (XRD) analysis indicates that magnetite (Fe3O4) is the most predominant phase, with lepidocrocite (γ-FeO(OH)) in smaller proportion. The shape and average particle size is altered by the application of a magnetic field during NPs synthesis. The average size of crystallite calculated with Scherrer’s equation were 30.30 nm without EXMF and 18.37 nm with EXMF. Using electron microscopy techniques (SEM, TEM), NPs with regular shapes were identified when the EXMF was applied. Meanwhile, irregular shapes were observed when the EXMF was not applied. Some NPs with nanoflake shapes and the crystalline phases γ-FeO(OH) were also identified. High-resolution transmission electron microscopy (HRTEM) showed that the NPs with regular shapes are of Fe3O4.

Cu–Al–Ni shape memory alloys have good thermal stability and shape memory properties, but mechanical working of these alloys is very difficult due to inter-granular fracture and brittleness. This paper deals with improvement of shape memory properties and ductility of these alloys with the addition of boron. It was observed that with addition of boron in a designed experiment, ductility improved by more than four times than that of the base alloy. In addition, shape memory properties also improved significantly. These results obtained are discussed in this paper systematically.

The newer route of poly (ethylene glycol) (PEG) stabilized the cesium lead iodide (PEG-CsPbI3) light-absorber have prepared for Inorganic perovskite solar cell application. The prepared PEG-CsPbI3, uniform multicrystalline growth on the electrode surface and surface morphologies were observed by the high resolution-tunneling electron microscopy and scanning electron microscopy. PEG-CsPbI3 is in black color cubic crystalline phase at 350 °C that results confirmed by X-ray diffraction pattern. Also, the cubic nature is confirmed through that selected area electron diffraction pattern. From the Fourier transform-infrared spectra, the functional groups of cesium, lead hydroxide and Pb-I-Pb stretching vibrations and the relevant frequency modes is confirmed. The current-voltage curves at 10 mV/S scan rate are performed in the two different directions. The PEG-CsPbI3 coated photo-anode stability is monitored through forward and reverse scan direction maximum 25 days, 3.01% of the average efficiency is achieved by in the 20th days stabilized device, particularly in the reverse scan.

Al2O3 supported ferrous catalyst promoted by manganese was successfully designed and developed by incipient wetness impregnation method. The synthesized compound was effectively characterized by various analytical techniques such as X-ray Diffraction (XRD), Scanning Electron Microscopy (FESEM-EDX) studies, Porosimetry analysis and Thermo Gravimetric Analysis (TGA). SEM images showed that the obtained particles are irregular in shape with extensive particle agglomeration. Furthermore, BET analysis revealed that the nanoparticles have a surface area of 53.66 m2 g−1 with an average adsorption pore diameter of 91.1464 A. The average crystallite size of the nanoparticle ranges from 19 to 20 nm was examined by XRD analysis.

Dual acceptors, Phosphorous and Nitrogen, were simultaneously doped into zinc oxide crystallite structure for achieving stable p-type conductivity through simple spray pyrolysis technique. Doping concentration was varied from 0 to 1.25 at% in steps of 0.25. The structural, morphological, optical and electronic properties were investigated for phosphorous and nitrogen doped ZnO (NPZO) samples. Furthermore, the optimized p-type film was used for fabricating homojunction with aluminium doped n-type layer (AZO) which was also deposited using spray pyrolysis. The IV characteristics shows the diode behavior of the created homojunction from which the ideality factor was calculated to be 3.16.

Highly crystalline copper indium disulfide (CuInS2) nanospheres morphology thin film have been deposited on fluorine-doped tin oxide (FTO) substrate by a single step using an electrospray chemical aerosol deposition (ESCAD) technique. The structural, optical, morphological and electrical properties of the CuInS2 nanospheres thin film is highlighted in this letter. Nanospheres CuInS2 film exhibits hexagonal wurtzite crystal structure with polycrystalline nature. The observed optical absorption in the infrared (IR) and visible region for CuInS2 semiconductor indicates narrow band gap (Eg) nature. Further, Eg value calculated using Tauc’s plot which is found to be 1.47 eV. The formation of well-interconnected spherical shaped CuInS2 nanospheres is portrayed from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. The photoconductivity of prepared CuInS2 nanospheres morphology film shows significant photocurrent response. The controlled fine aerosol formation in ESCAD leads to the spherical shaped CuInS2 nanospheres deposition on FTO substrate result in pronounced electrical and photophysical properties. So, this work could be facilitated a special interest in developing optoelectronic and photovoltaic devices.

Nanostructure cathode material with composition of La0.10Sr0.90Co0.20Zn0.80O5-δ (LSCZO) was synthesized by wet chemical route. The crystallite size was found 47.55 nm and porosity was observed in the structure. The oxygen ion and electron transport phenomena were studied from anode to cathode and vice versa by electrical conductivity and electrochemical performance studies. The conductivity measurements were carried and found 20.29 and 4.87 S/cm2 in air and hydrogen atmosphere, respectively. The area specific resistance (ASR) was observed 0.07 Ω/cm2 at 550 °C. Arrhenius plots were drawn to calculate activation energy and found to be 0.09 eV. Excellent performance of 850 mW/cm2 has been recorded at 550 °C.

The pressure-dependent electronic properties of polycrystalline β-Ag0.33V2O5 were investigated and a discontinuous change of electrical resistance is found at around 4.5 GPa, where semiconductive-like decreasing trend before 4.5 GPa and a metallic-like increasing trend after 4.5 GPa with increasing temperature was observed. Furthermore, high temperature/pressure treatment can markedly reduce the semiconductor-metal (S-M) transition pressure to around 1.5 GPa. The results indicate a promising way for engineering the electronic properties of polycrystalline Ag0.33V2O5, and this pressure/temperature induced semiconductor-metal switch may have potential applications in electronics field.

The present study, for the first time, revealed the athermal recrystallization behavior at a heterogeneous metallic interface using room temperature electromigration. The athermal recrystallization occurred within the meta-stable amorphous Cu-Sn interphase, which was formed during the early stage electromigration, for stress relaxation after further electromigration. The nano-scale polycrystalline (Sn) interphase was favorably recrystallized at the intermetallic-free Cu/Sn interface where the current crowding effect occurred. Athermal electromigration force facilitated the nucleation of Sn nuclei through the kinetic energy provided by the electron momentum transfer. The formation of the recrystallized (Sn) interphase is believed to be an intermediate material interaction product prior to further intermetallic nucleation under room temperature electromigration.

The physical and electrical properties of magnetron sputtering fabricated (Fe, N) co-doping tin oxide thin films were investigated. The deposited films are in polycrystalline tetragonal structure. No Fe metal clusters or secondary phases are formed. All the films display n-type conductivity and the carrier concentration of (Sn1−xFex)O1.982N0.018 films, x = 0, 0.023, 0.042, 0.075 and Sn0.987Fe0.013(O2−yNy) films, y = 0, 0.038, 0.091, 0.130 decrease monotonically with Fe and N co-doping. Transport mechanism of the films can be attributed to the Mott variable range hopping (VRH) model. The SnO1.982N0.018 films showed maximum optical transmittance 90% in the visible region. The red-shift in the band gap energy can be attributed to the sp-d exchange interaction between the SnO2 band electrons and the substitutional N for O in SnO2 lattice.

The method utilizing high-pressure torsion (HPT) processing followed by annealing to fabricate Cu-Al in situ composite with enhanced mechanical properties is presented. The initial sample consists of three metal discs Cu/Al/Cu was processed by HPT (5 GPa, 5 turns). The analyses of the microstructure after HPT carried out by transmission electron microscopy and scanning electron microscopy equipped with energy dispersive spectrometry (EDS). After HPT, the development of nanostructure with the mean crystallite size of about 100 nm in the produced sample was revealed with the small presence of the intermetallic phases. Investigation of the kinetics during subsequent annealing at 450 °C/30 min showed the in situ formation of intermetallic Al2Cu, AlCu, Al3Cu4, Al2Cu3 and Al4Cu9 phases in the copper matrix which was detected by EDS. The formation of intermetallic phases after annealing was also confirmed by X-ray diffraction. The results showed that microhardness of the composite considerably increases from an initial value of ∼ 380 for HPT sample to a saturation value of ∼ 900 after annealing.

In this work, we prepared BiCuSeO polycrystalline films by evaporating precursors following with selenization treatment. Their optical and photoelectrical properties were investigated from visible to infrared light. Optical absorption spectrum indicated that the absorption coefficient was 104–105 cm−1 from 0.4 μm to 2 μm. Photo induced voltages were clearly detected when the film surfaces were irradiated by the lasers with various wavelengths and powers. The voltage had a linear dependence with the laser illumination intensity, which indicated the main response mechanism of photo-thermal electric effect in the films. All the results suggested that the BiCuSeO film was a potential material for near infrared detector application.

Co38Ni35Al27 and Co35Zn10Ni32Al23 ferromagnetic shape memory alloys were prepared via facile powder metallurgy and vacuum sintering technique. The influence of sintering temperature on phase transformation behaviour, microstructure and magnetic properties were investigated. The rise in peak intensity of A2-phase shows that the alloy is rich in martensitic-phase in the polycrystalline cubic B2-phase structure and Zn incorporation leads to the reduction in austenite-phase. The needle-shaped cobalt precipitates on predominant martensite A2-phase, shows Widmanstatten-like structure in the samples sintered at 673 K. The saturation magnetization was found to be 87.92 and 96.2 emu/g for Co38Ni35Al27 and Co35Zn10Ni32Al23 alloy. The existence of non-interacting single-domain particles were observed and proved using Stoner-Wohlfarth model.

Pure and Bi doped ZnO thin films prepared by Successive Ionic Layer Adsorption and Reaction (SILAR) method. The structural analysis shows that prepared films are polycrystalline in nature with preferential orientation along (1 0 0), (0 0 2) and (1 0 1) planes. Scanning electron microscope shows the morphological changes of the films with respect to increase in doping concentration. The average optical absorption value of all films was in the near visible range and the band gap of the films varies from 3.21 to 3.17 eV. The gas sensing study shows a maximum response of the films at 1000 ppm of ethanol was found to be around 60% with an operating temperature of 400 °C.

High quality methylammonium lead iodide (MAPbI3) perovskite powder was prepared by anti-solvent assisted method in large scale. Structure, optical and morphology were tuned with respect to the temperature. Four different structures such as intermediate, mixed or polycrystalline, tetragonal and cubic were prepared. The absorption edge of the tetragonal MAPbI3 was located at about 850 nm, indicating that the band gap of MAPbI3 is approximately 1.48 eV, which is close to the theoretical results and smaller than those derived from polycrystalline and thin-films. MAPbI3 powder exhibits relatively wide absorption (from 250 nm to 850 nm) and good thermal stability.

Undoped and Eu doped ZnO (EZO) nanoparticles were prepared by sol–gel coprecipitation whose average crystallite size lies within the range of 27.83–64.15 nm. The band gap showed a monotonous redshift with Eu doping from 0 to 6 at. %. Photoluminescence (PL) emission spectra of undoped ZnO contained three major peaks at 388, 467 and 563 nm out of which the first peak showed redshift with Eu doping. The higher amount of microstrain was found to cause blueshift at the level of 2 at. % Eu doping. Reduction of temperature from 30⁰C to −10 °C was found to enhance the blue emission intensity of PL peaks in EZO. Vertically grown nanostructures demonstrated better luminescence behaviour. EZO has strong potential for thermal sensing and bioimaging.

Green synthesis of Aloe Vera (AV) extracts with metal nanoparticles (NPs) is a promising method for developing highly effective medicinal drugs. However, the plant extract with metal NPs is not good for human health. The pure plant has more medicinal properties than metal NPs and allopathic medicine, but the plant with micro-sized particles does not efficiently treat diseases immediately. The synthesis of pure plant extracts in the range of nanosized particles had not been reported elsewhere. In this research, we discovered AV particles with a nanometer size range (without any metal NPs) by employing a new photon-induced method (PIM). X-ray diffraction (XRD) results indicated that the average crystallite size was 28 nm and more, confirmed by dynamic light scattering (DLS). We recommend these cheap and environmentally friendly biosynthesized NPs for production of green pharmaceutical drugs.

This paper reports the facile hydrothermal synthesis of Co(OH)F crystallites on a nickel-foam (NF) substrate for the oxygen evolution reaction (OER). Scanning and transmission electron microscopy showed that the as-synthesized Co(OH)F crystallites consisted of different rhombohedral, octahedral, and decahedral shapes, 0.3–0.5 μm in size. The desired Co(OH)F catalyst synthesized in this study delivered a lower overpotential of 273 mV at a current density of 10 mA cm−2, with a smaller Tafel slope of only 45 mV dec−1, compared to other fluoride-containing catalysts because of their unique structural features, higher double-layer capacitance, and rapid charge transfer. Furthermore, a stable potential was maintained for more than 20 h during the chronopotentiometry test at a constant current density of 10 mA cm−2.

Ga2O3 films were deposited on non-polar sapphire and epi-GaN substrates at low temperature by MOCVD. The e-Ga2O3 films, which were preferentially grown along the (0001) crystal plane family, were obtained on a-, r-plane sapphire and GaN substrates, and contained a certain polycrystalline component. On the m-plane sapphire substrate, a polycrystalline film containing α/β-Ga2O3 was obtained. The grain size and surface fluctuations on m-plane sapphire substrate were large, while the film on r-plane sapphire and GaN substrates had more uniform surface and the film on GaN substrate had the flattest surface. Optical analysis indicated that the best quality Ga2O3 film on these sapphire substrates was deposited on r-plane substrate. XRD showed that the Ga2O3 film on GaN substrate had better crystalline quality than that on a-plane sapphire substrate.

In the present work, defects mediated optical emission and efficient photodetection characteristics of ZnO:Ag (0, 2, 5, and 7 wt%) nanoparticles (NPs) synthesized by sol–gel method have been investigated for UV sensor. X-ray diffraction (XRD) patterns show the polycrystalline nature of ZnO NPs. The crystallite sizes corresponding to most intense peak (1 0 1) are found to be in the range of 10–20 nm. Effective enhancement of defect-mediated visible emissions is observed in Ag-doped ZnO NPs. Red-shift of UV peak in Ag-doped ZnO may be due the tensile strain upon Ag doping. Pure ZnO exhibits anomalous UV sensing, which is absent in ZnO NPs doped with Ag. The 7 wt% Ag-ZnO NPs is found to efficient UV photoresponsive. The results obtained by doping of Ag contents in the ZnO can be capable for making efficient and consistent prototype UV sensors.

A high-performance ZnS-based UV photodetector (PD) with novel nanoparticle-anchored silver nanowires (NP-anchored Ag NWs) networks as enhanced platform is reported. The materials’ d-spacing and crystallite size were calculated using XRD date which are in good agreement with HRTEM results. Benefitting from the plasmonic gap effects in the NP-NW junctions, the fabricated photodetector yields a fast response speed (tr = 0.04 s and td = 0.05 s), decent on/off ratio (4 8 2), high responsivity (1.8 × 103 A/W) and excellent detectivity (3.3 × 1013 Jones). The strategy presented in this work may be instructive for designing high-performance optoelectronic devices.

To obtain comprehensive materials with both high temperature coefficient of resistivity (TCR) and magnetoresistance (MR) at low magnetic fields, the polycrystalline La0.72−xNdxCa0.28MnO3(x = 0.02, 0.04, 0.06, and 0.08) were synthesized using the sol–gel method, which is a significant practical application in magnetic sensors and bolometers. We observe an enhancement of TCR and MR by substituting La3+ with Nd3+. The excellent TCR (19.21 %·K−1) and MR (73.10 %) are observed in La0.68Nd0.04Ca0.28MnO3 at the 1 T magnetic field. Meanwhile, the maximum TCR reaches 22.68 %·K−1 without a magnetic field. This substitution increased the total magnetic moment and a slight increase in average grain size. The Mn3+ and Nd3+ spin within the disordered region realign along the field direction with a magnetic field. Therefore, Nd-doped La0.72Ca0.28MnO3 ceramic materials can effectively improve the material properties.

Temperature conditions are significant for the crystal structure formation of prospective cathode materials, determining their further performance and cycle life. The paper presents the results of a detailed analysis of the multilayer thin films before and after heat treatment. The investigated multilayer structures consist of a two-layer system of an amorphous nickel-doped Li-O layer and a NiO·CoO layer obtained by atomic-layer deposition on Si substrate. It was shown that annealing at 800 °C for 5 min is sufficient to form a crystalline film with energy favorable spherical-like Li-Ni-Co-O structures on the surface with a size of 50–150 nm. Chemical mapping after heat treatment using EDX showed the formation of Ni-rich (spherical-like structures) and Co-O intermediate layers. The electron energy loss spectroscopy results confirm the presence of Li in the top Ni-rich layer and are embedded in its crystalline structure. X-ray and electron diffraction showed a polycrystalline cathode structure of lithium-containing nickel and cobalt oxides.

Quick detection of pharmaceutical drugs, such as paracetamol, pantoprazole sodium, and diclofenac sodium, by localized surface plasmon resonance (LSPR) Raman using novel meniscus confined electrochemical additive manufacturing (ECAM) printed silver nanoparticle substrate is studied. The ECAM printing process produced pure phase silver substrates without any impurity, and the quality of the electro-deposited substrates is analyzed by optical and scanning electron microscopy. The electro-deposited nanoparticle substrate has average crystallite and particle size 18 nm and 60 nm respectively. The LSPR Raman spectra show up to four times enhancement in the original Raman signals.

Boron (B) and yttrium (Y) single/co-doped titanium dioxide (TiO2) nanoparticles were prepared by a sol-gel method followed by calcination at 600 °C. The results show TiO2 doped with B and Y ions can reduce the crystallite size, improve the specific surface area and broaden the optical response range. The calculation results of density of states and charge density reveal that B doping leads to electron redistribution of the O 2p state and promotes the ability of the surrounding Ti 3d and Y 5d state to capture electrons.

ZnO films grown on Si(100) substrate through radio frequency (RF) sputtering are subjected to 100 keV Ni ion beam at different fluence ( 1 × 10 16 , 2.5 × 10 16 and 5 × 10 16 ions/cm2). High resolution X-ray diffraction revealed the increase in crystallite size and development of stress gradient in the ZnO thin films with the increasing Ni ion fluence. Ni implanted ZnO/Si(100) films exhibits room temperature ferromagnetism (RTFM) which is discussed via defect induced bound magnetic polaron model. Near-edge X-ray absorption fine-structure (NEXAFS) measurements at Ni L 3 , 2 -edge confirm the nature of implanted Ni ion inside the ZnO matrix. Further, NEXAFS at O K-edge revealed the onset of O(2p) with Ni(3d) orbital states, which is correlated with the observed RTFM.

Exfoliated graphite was obtained by thermal treatment at temperatures of 600, 800, 1000 °C of expandable graphite based on graphite bisulfate of I, II, III and IV stages. The aim of this work is to study the influence of stage number and exfoliation temperature on macrostructure and microstructure of exfoliated graphite. The delamination of expandable graphite particle is observed with decreasing stage number of initial graphite bisulfate. The obtaining of exfoliated graphite is accompanied by formation of graphite cellular structure. The dependence of crystallite size along c axis of exfoliated graphite on stage number and exfoliation temperature was investigated. Crystallite size is reduced both with decreasing stage number of initial graphite bisulfate and with increasing exfoliation temperature.

Several rare earth (RE)-doped TiO2/Sepiolite (RE-TiO2/Sep) photocatalysts were prepared via microwave-hydrothermal treatment using six different types of RE ions: La, Ce, Pr, Nd, Eu or Gd. The obtained nanocomposites were characterized by using XRD, SEM and TEM techniques. The results revealed that the structures of the nanocomposites were significantly dependent on the radius of the RE3+. Since the radius of RE3+ is much larger than that of Ti4+, the doped RE species were not incorporated into the matrix of TiO2 but rather lie in the grain junctions and boundaries of titania. By forming the Ti-O-RE bonds, the crystallite growth of titania can be inhibited owing to the relatively larger radii of RE3+ ions.

Highly ordered and reproducible Gd nanowires have been reported via DC electrodeposition method. In this regard, templates with different diameters 100 nm, 50 nm and 20 nm were utilized. Shape morphology, reproducibly and homogeneity of nanowires were investigated with field emission scanning electron microscopy (FE-SEM). Morphological analyses confirm as required diameter, length and aspect ratio. Structurally, body centered cubic (bcc) phase was observed with Rietveld refinement of X-ray diffraction (XRD) patterns for all diameters. Magnetic investigations are including zero field cooled (ZFC) and field cooled (FC) and hysteresis measurement by using physical property measurement system (PPMS). These magnetic analyses of nanowires embedded in AAO templates predict mix phase with superparamagnetic and ferromagnetic clusters.

The hexagon-like ZnO microstructure has been prepared at low temperature via hydrothermal method without using any surfactant, organic solvent or capping agent. ZnO belongs to hexagonal wurtzite structure. The formation of hexagon-like microstructure, with the grain size of about 480x720 nm (from SEM), is possibly due to assembling of many crystallites (crystallite size of 45–51 nm, from XRD). The blue emission over 420–500 nm may originate from the radiative combination due to surface defect states. ZnO showed high photodegradation efficiency of 95% after 80 min. The photodegradation reaction follows the pseudo first-order kinetics. ZnO photocatalyst retains its original efficiency (98%) even after the third cycle of reuse indicating the advantages of stability and reusability.