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This study explored the structural, vibrational, morphological, optical, and magnetic characteristics of both as-grown and annealed single crystals of tin telluride (SnTe), employing diverse analytical techniques. X-ray powder diffraction (XRD) analysis shows the cubic lattice structure of SnTe with consistent lattice parameters across different temperatures, along with the phase transition phenomenon. Fourier Transform Infrared Spectroscopy (FTIR) elucidates temperature-induced shifts in vibrational modes, indicating sensitivity to thermal stimuli. Scanning electron microscopy (SEM) reveals layer-by-layer growth patterns and temperature-dependent variations in crystal morphology. Energy-dispersive X-ray analysis (EDAX) confirms the synthesized crystals' high purity and slight tellurium-rich composition. Optical band gap measurements demonstrate an increase in band gap upon annealing, attributed to valence band convergence. Field-dependent magnetization (M − H) curves exhibit ferromagnetic properties at ambient temperature, which escalate with increasing annealing temperature. Electron Paramagnetic Resonance (EPR) spectra reveal spin mobility and exchange coupling, with variations in the g-factor suggesting the presence of additional spin entropy. These observations offer significant insights into the complex properties of SnTe, which are crucial for its potential applications across various technological fields. [ABSTRACT FROM AUTHOR]

Iron silver oxide (AgxFe2−xO3; 0xFe2−xO3 shown in the figure can be indexed to the hexagonal structure of silver oxide and the rhombohedral structure of hematite and new X-ray Diffraction (XRD) peaks of AgxFe2−xO3 structure. The annealing and doping process seems to cause a serious change in the crystal structure of the thin film, it showed a serious change in its electrical properties. The electrical parameters of resistance for thin films were measured using the Hall measurement method at room temperature. With Hall measurements, the n-type carrier concentration of the Fe2O3 structure was calculated, and it was observed that its resistance was 1MΩ. Likewise, it was observed that AgxFe2−xO3 exhibited an n-type carrier concentration, and its resistance was calculated to be 0.5MΩ. The conductivity change is based on silver doping. The doping process seems to cause a change in the bandgap of the thin film, it showed a change in its optical properties. The film’s optical absorption was measured by UV–Vis photo spectroscopy. Subsequently, the structural and topographic properties of AgxFe2−xO3 structures were investigated by high-precision characterization devices. [ABSTRACT FROM AUTHOR]

The effects of vacuum and oxygen annealing on Sr2-xNbxIrO4 samples have been systematically investigated. The annealing under vacuum leads to an enhanced insulating state of the Sr2-xNbxIrO4 compounds, which could be due to the evaporation of oxygen atoms which breaks the superexchange interaction between Ir and O ions. The annealing under oxygen atmosphere results in substantial straightening of the in-plane Ir–O–Ir bond and rapid depression of the canted antiferromagnetic ordering state. Importantly, the insulator-to-metal transition has been achieved by oxygen annealing of the Sr2-xNbxIrO4 samples, which could be due to the enhanced hybridization of Ir 5d orbitals with the neighboring O 2p orbitals. The present results suggest that the annealing treatment could be an effective way for exploring of novel physical phenomena in Sr2IrO4 and related compounds. [ABSTRACT FROM AUTHOR]

The effects of vacuum and oxygen annealing on Sr2-xNbxIrO4 samples have been systematically investigated. The annealing under vacuum leads to an enhanced insulating state of the Sr2-xNbxIrO4 compounds, which could be due to the evaporation of oxygen atoms which breaks the superexchange interaction between Ir and O ions. The annealing under oxygen atmosphere results in substantial straightening of the in-plane Ir–O–Ir bond and rapid depression of the canted antiferromagnetic ordering state. Importantly, the insulator-to-metal transition has been achieved by oxygen annealing of the Sr2-xNbxIrO4 samples, which could be due to the enhanced hybridization of Ir 5d orbitals with the neighboring O 2p orbitals. The present results suggest that the annealing treatment could be an effective way for exploring of novel physical phenomena in Sr2IrO4 and related compounds. [ABSTRACT FROM AUTHOR]

Developments in low-cost techniques for growing high-quality nickel oxide thin films (NiOTFs) are critical enablers for the fabrication of NiO-based devices, particularly solar cells, light-emitting diodes, lasers, and many other applications. In this study, it has been demonstrated that the optical, electrical, and structural characteristics of NiOTFs coated on glass substrate employing a low-cost solution method are strongly influenced by post-thermal annealing treatments in ambient air. A comprehensive study was carried out on the characteristics of the deposited NiOTFs. X-ray diffraction (XRD) measurements indicate the enhancement of the crystal quality of films after annealing. There is a noticeable change and improvement in coated NiOTFs with heat treatment at 300 and 600 ℃ due to clear shifts in density. During the heating temperature increment, the energy of the band gap was shifted from 3.63 to 3.44 eV, and the electrical resistance of the NiOTFs varied from 1020 to 700 Ω-cm. Furthermore, the results indicate that the low-cost sol-gel (SG) deposition technique has a greater potential for producing high-quality p-type NiOTFs with minimal defects for electronic device applications. [ABSTRACT FROM AUTHOR]

Atomic scale study has been carried out to probe the pyrochlore phase formation in local scale and compare it with the long range ordering. Lanthanum zirconate (La2Zr2O7) pyrochlore was synthesized by wet chemistry and characterized by X-ray diffraction to study the long range ordering. Time Differential Perturbed γ-γ Angular Correlation (TDPAC) Spectroscopy was performed to identify the pyrochlore phase formation in local scale. Electron paramagnetic resonance and Photo-luminescence spectroscopic studies were used to identify the defects in local scale. Role of annealing and defects in nucleation of pyrochlore phase has been explored in the present study. An early identification of pyrochlore phase was successfully done by TDPAC spectroscopy. [ABSTRACT FROM AUTHOR]

The octahedral family of NiO nanoparticles is gaining significant attention as an assembly with unique physicochemical properties and outcomes in electromagnetics, shielding and absorption applications. In this study, a mesoporous Ni60%SiO2(Comm), chosen owing to its NiO species existing in an octahedral shape, was evaluated for synthesis gas (syngas: H2(g) and CO(g) mixtures) production via combined steam and dry reforming of a model biogas mixture (T = 800 °C, (H2O(g) + CO2(g))/CH4(g) = 1.2). In comparison with a standard Ni5%SiO2 (Aerosil)-based catalyst, a different family of NiO species was deposited on the silica matrix with an average particle size being 4.5 times greater. This led to a completely different reducibility behavior with the majority of NiO species (around 80%) undergoing reduction at low temperatures, while around 66% of those impregnated on the Aerosil silica underwent reduction at higher temperatures. This has been accompanied by a major shape transformation from arrays of octahedral NiO geometries into metallic grids of metallic Ni0 appearing over Ni60%SiO2(Comm). In terms of reactivity outcomes, slightly higher reactivity levels along with significantly lower amounts of carbonaceous deposits were obtained over Ni60%SiO2(Comm) for 10 h on stream, under harsh conditions of temperature and steam-rich atmosphere. The high-coke resistance of originally shaped NiO octahedra was ascribed to an annealing effect, generated during H2(g)-treatment (prior to catalysis), yielding mesoporous metallic Ni0 nanorods with H2(g)-storage capacities. Stored hydrogen within Ni0 layers acted as active centers for continuous in situ coke gasification, preventing thus C(s) accumulation while keeping Ni0 sites accessible for catalysis. [ABSTRACT FROM AUTHOR]

2D transition metal dichalcogenides have been studied extensively in the field of electronics and photonics. Among them, the molybdenum chalcogenides have been receiving considerable attention due to their potential usage in field‐effect transistors and biosensors. Despite such promising aspects of these materials, studies regarding temperature effects on MoSe remain relatively rare. Herein, MoxSey (x = 0 ≈ 10, y = 0 ≈ 2) thin films are fabricated by radio frequency (RF) magnetron cosputtering on silicon and investigated using scanning electron microscopy for various atomic ratios and annealing temperatures from room temperature to 500 °C. Above the melting point of Se, Se evaporates and forms a layer, subsequently leading Mo to be exposed on the surface of the thin films. From the X‐ray diffraction and X‐ray photoelectron spectroscopy results, silicon peaks are observed due to the evaporation of Se. In addition, both Mo and Se are oxidized at above 300 °C. The work functions of the MoxSey thin films show the highest value at 200 °C measured by ultraviolet photoelectron spectroscopy and a Kelvin probe. Above the melting point of Se, there is a tendency for the work function to decrease due to the influence of Mo. [ABSTRACT FROM AUTHOR]

An alpha particle-irradiated MIS device made of AuTa 2O 5GaAs was used to study how thermal annealing affects the I-V characteristics and how the current changes with annealing temperature, radiation energy, and voltage biassing. The super-gate of the MIS structure was made by using thermal evaporation to build a 1000°A thick layer of gold under a vacuum of about 10-5 torr. At room temperature, the devices were exposed to alpha particles from the radioactive source 226 Ra (0.5 Ci) with energies of 5.1, 4, 3, 1.8, and 1.2 MeV for 0–30 minutes. After 30 minutes of annealing at 150, 200, and 300 °C in a vacuum of 10-3 torr, the current-voltage (I-V) characteristics of the irradiation devices were found. During thermal annealing, different results were seen with bias voltages of 0.4, 1, and 2 V and temperatures of 150, 200, and 300 ° C. Annealing the device at 150 °C doesn't change how stable it is, but annealing it at 300 °C causes ohmic conduction in the device's properties. The device's current can be fixed best when the device is heated to 200 °C and then cooled. Also, thermal annealing seems to have different effects on the I–V electrical characteristics of the devices depending on the energy of the particles and the voltage biassing. [ABSTRACT FROM AUTHOR]

Ga-doped ZnO translucent ceramics were prepared by spark plasma sintering and annealed at temperatures of 600, 650, 700, 750, and 800 °C for 24 h in air. The scintillation and optical properties of the non-annealed and annealed ZnO:Ga translucent ceramics were investigated. An absorption band from 550 to 800 nm was observed in the diffuse transmittance spectra of all the ZnO:Ga samples. In the scintillation spectra, all the ZnO:Ga samples exhibited defect-related emissions peaking at 500 nm under X-ray irradiation. Among the samples, the annealed ZnO:Ga translucent ceramic sample annealed at 700 °C showed the highest light yield (12000 photons/5.5 MeV-α). [ABSTRACT FROM AUTHOR]

In this work, Sn-doped Ga2O3 films fabricated using plasma-enhanced atomic layer deposition were treated by rapid thermal annealing (RTA). The RTA influence on the chemical state, surface morphology, energy band alignment, and electrical properties of Sn-doped Ga2O3 films were thoroughly investigated. The results of X-ray photoelectron spectroscopy (XPS) demonstrated that Sn atoms were successfully doped into these films. Moreover, energy band alignments were obtained by the energy-loss peak of the O 1s spectrum and valence band spectra and thoroughly discussed. X-ray reflectivity (XRR) and atomic force microscope (AFM) measurements indicated that the Sn-doping level affects the interfacial microstructure and surface morphology. As the Sn content increases, the film thickness decreases while the roughness increases. Finally, the leakage current-voltage (I-V) characteristics proved that the Sn-doped Ga2O3 films have a large breakdown field. In I-V tests, all metal oxide semiconductor (MOS) capacitors exhibited a hard breakdown. This research demonstrates a method for manufacturing high-performance optoelectronic devices with desired properties. [ABSTRACT FROM AUTHOR]

This study used a simplified, automated spray pyrolysis setup with a perfume atomizer to prepare nitrogen (N) doped ZnO thin films. The deposited thin films were annealed at 300 ºC to 500 ºC under a nitrogen atmosphere. In the present work, detailed investigations are carried out on the effect of annealing on structural, optical, and surface morphological, photoluminescence, and electrical properties of p-type ZnO:N thin films. The effect of annealing temperature on the photocatalytic activity of N-doped ZnO thin films was studied, the degradation efficacy was and 91%. The XRD diffractograms depicted that all the prepared films have a wurtzite structure, high crystallinity, and C-axis orientation. The increased annealing temperature received a red shift in the band gap. A flake-like morphology was observed from SEM images. The p-type to n-type conductivity transformation is kept at the maximum applied annealing temperature of 500 ºC. A resistivity received ∼ 21.7 Ω cm was obtained for 400 ºC annealing temperature. Photocatalytic studies confirmed that higher degradation efficiency was exhibited for higher annealing temperatures. The present investigations reveal that the properties of p-ZnO:N thin films are highly suitable for optoelectronic applications.

Bulk chalcogenide glass materials of Se80Te20-xInx (x = 0, 3, 6, 9 and 11) were prepared via the melting-quenching technique. Se80Te20-xInx thin films were evaporated thermally on glass substrates. The results of this study revealed that In doping and annealing time resulted in significant tailoring of some physical properties of Se80Te20-xInx thin films. The annealing process changes the amorphous nature of Se80Te20-xInx thin films to a crystal one. As both In content and annealing time increase, crystallite size decreases and internal lattice strain increases for all samples except those with x = 11. Refractive indices for Se80Te20-xInx thin films were fitted according to the main parameters of the single-oscillator model. It was also discovered that Se80Te20-xInx thin films have a high absorption of high-energy photons. The increasing annealing time improves the refractive index. The bandgap got smaller when the annealing time was increased. [ABSTRACT FROM AUTHOR]

Because of the precise control of film thickness, atomic layer deposition (ALD) offers significant advantages in fabricating high-quality superlattice films. For the first time, a SiN x /SiO 2 superlattice with an ultrathin SiN x sublayer layer (1.5 nm) and a SiO 2 barrier layer (3 nm) was successfully fabricated using plasma-enhanced ALD. Transmission electron microscopy (TEM) measurements demonstrate the maintenance of multilayer structures with smooth interfaces. Next, the annealing effect on the microstructural, optical, and chemical properties of these SiN x /SiO 2 superlattice structures was thoroughly investigated. With increasing annealing temperature, X-ray reflection (XRR) and TEM measurements revealed consistent changes in interface, morphology, roughness, density, and thickness. After high-temperature annealing, Fourier-transform infrared spectroscopy (FTIR) measurements combined with X-ray photoelectron spectroscopy (XPS) measurements revealed significant reductions in Si–H-related defects and absorption bands. Photoluminescence (PL) was used to characterize the light emission property, and it was discovered that increasing the annealing temperature decreased the PL peak intensity at ∼550 and 900 nm. The silicon nanocrystals (Si–NCs)-related PL peak (∼900 nm) became dominant as the annealing temperature increased. The findings in this paper shed light on the annealing effect on the new superlattice material prepared via ALD. Improved PL properties of this type of superlattice are expected and can be obtained in future research by optimizing the ALD deposition process and annealing parameters. [ABSTRACT FROM AUTHOR]

In this study, molybdenum oxide nanostructures (MoO 3 NSs) were effectively synthesized through a simple, low-cost, surfactant-free, low-temperature, and scalable chemical co-precipitation method and investigated their synergistic effect with annealing temperature on energy storage applications for the first time. Herein, we have reported a phase transition of MoO 3 NSs from hexagonal to orthorhombic after the annealing temperature varied from 100°C to 500°C at constant time. Additionally, the resultant NSs were thoroughly examined for their physio-chemical characteristics, which revealed the stable phase formation of the MoO 3 NSs, respectively. Furthermore, the electroactive MoO 3 NSs were pasted on Ni-foam substrate (M@NF), and electrochemical properties were evaluated using a three-electrode setup at room-air temperature in 1 M KOH aqueous electrolyte across the potential range of 0 V to 0.786 V. As a result, the M@NF-5 electrode exhibited an impressive specific capacitance of 976.84 F g−1 at a scan rate of 1 mV s−1, a higher energy density of 73.69 Wh kg−1, and a power density of 655 W kg−1 at 5 mA g−1. The non-linear galvanostatic charge-discharge (GCD) profile aligns well with the cyclic voltammetry (CV) analysis. Both CV and GCD techniques confirm the pseudocapacitive behavior, with 83% capacitive retention observed after 2000 cycles. The fabricated symmetric device (M@NF-5//M@NF-5) exhibits enhanced electrochemical performance with a specific capacitance of 67.35 F g−1 at 5 mA g−1 and with an energy density of 18 Wh kg−1, and a power density of 1750 W kg−1 at a specific current. These findings underscore the potential of chemically deposited α-MoO 3 as an auspicious material for use in supercapacitor applications. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, the effect of annealing on the ZnO/Cu/ZnO films prepared by an RF/DC magnetron sputtering system was studied. Structural, optical, and thermal properties of both the as-prepared samples and their annealing data were systematically investigated. Our evaluation shows that these layers can be used as suitable coatings in energy storage applications. The ZnO/Cu/ZnO sample after annealing at 400 °C has the lowest resistivity (14.04Ω/sq), highest FOM (6.37 × 10−4 Ω−1), and lowest emissivity (0.16). It can also be chosen as the best coating on building windows to save energy because of its high transmittance at 550 nm (68%) and low U-value (1.63 W/Cm2.K). [ABSTRACT FROM AUTHOR]

We synthesized a 0.1% Li-doped ZnO translucent ceramic using spark plasma sintering (SPS) and annealed it at 700 or 800 °C in air. The photoluminescence (PL) and scintillation properties of all samples were evaluated. The PL quantum yield (QY) and scintillation light yield (LY) were improved by annealing owing to the reduction in the number of oxygen defects in comparison with the as-prepared sample. Among the translucent ceramic samples, the sample annealed at 700 °C showed the highest LY (5800 ph/5.5 MeV-a); the scintillation LY was lower in the sample annealed at 800 °C because of the increase in the number of trap sites. [ABSTRACT FROM AUTHOR]

A copper oxide (CuO) nanoparticle, a transition metal oxide with a wide variety of easy production methods, can be used as an antimicrobial agent against various types of bacteria. CuO nanoparticles were produced by the sol–gel method, annealed and structural characteristics and antimicrobial properties of these particles were investigated. Single-phase monoclinic of CuO nanoparticle formation was confirmed by X-ray powder diffraction (XRD) spectra, FTIR techniques, differential scanning calorimetry with thermal gravimetry were used to characterize. It was determined that annealing in the temperature range of 150–900∘C affects both structure and particle size and antimicrobial characteristics. CuO nanoparticle size was found to be between about 25–70 nm at 150–900∘C annealing temperature, which does not have this wide temperature range in the literature. These results were supported by the TEM micrographs of the CuO nanoparticles observed at 150∘C and 900∘C. The antimicrobial activity of the synthesized nanoparticles was tested with the disc diffusion assay against Staphylococcus aureus, Escherichia coli, Agrobacterium tumefaciens, and yeast Pichia pastoris. The antimicrobial properties of the nanoparticles first increased and then decreased and disappeared as the annealing temperature increased. The antimicrobial properties of CuO nanoparticles disappeared at 750∘C and above, while the maximum antimicrobial effect was at 300∘C. The inhibition zones were examined and similar results were observed in all tested microorganisms. CuO nanoparticles were produced by sol–gel method, annealed characteristics and antimicrobial properties of these particles were investigated. CuO nanoparticle size was found to be between about 25–70 nm at 150–900∘C annealing temperature. The antimicrobial activity of the synthesized nanoparticles was tested with disc diffusion assay against Staphylococcus aureus, Escherichia coli, Agrobacterium tumefaciens and yeast Pichia pastoris. The antimicrobial properties of the nanoparticles first increased and then decreased and disappeared as the annealing temperature increased. [ABSTRACT FROM AUTHOR]

In this paper, the technology of obtaining and effect of annealing on the morphology and optical properties of cadmium telluride thin films has been investigated. The effect of vacuum chamber modes on the growth of thin films has been studied. For obtained cadmium telluride thin films were used a modified thermal evaporation method deposited by Physical Vapor Deposition technique on a glass substrate with different thicknesses. The transmission measurements were carried with UV-ViS-NIR Spectrophotometer in the wavelength range 180-3300 nm, to analyze the optical properties as a function of wavelength. The optical band gap values were 1.49 eV for as-grown films and 1.46 eV after annealing. The refractive indexes of the samples were defined in the range of 2.6 – 2.8 for as-grown films and the indexes have increased after annealing depending on the wavelength region and film thickness. After annealing, the coalescence mode of growth is observed.

In this work, Sn-doped Ga2O3 films fabricated using plasma-enhanced atomic layer deposition were treated by rapid thermal annealing (RTA). The RTA influence on the chemical state, surface morphology, energy band alignment, and electrical properties of Sn-doped Ga2O3 films were thoroughly investigated. The results of X-ray photoelectron spectroscopy (XPS) demonstrated that Sn atoms were successfully doped into these films. Moreover, energy band alignments were obtained by the energy-loss peak of the O 1s spectrum and valence band spectra and thoroughly discussed. X-ray reflectivity (XRR) and atomic force microscope (AFM) measurements indicated that the Sn-doping level affects the interfacial microstructure and surface morphology. As the Sn content increases, the film thickness decreases while the roughness increases. Finally, the leakage current-voltage (I-V) characteristics proved that the Sn-doped Ga2O3 films have a large breakdown field. In I-V tests, all metal oxide semiconductor (MOS) capacitors exhibited a hard breakdown. This research demonstrates a method for manufacturing high-performance optoelectronic devices with desired properties.

The resonance of the E2High mode of the zinc oxide (ZnO) lattice occurs near a ridge‐like structure of the two‐phonon density of states (DOS). The renormalization of the harmonic frequency of the E2High mode using perturbation‐theory with first‐principles calculations of the two‐phonon DOS is usually used to describe the Raman spectrum of this mode. In this contribution, we tackle the inverse problem; that is, we derive the two‐phonon DOS in ZnO using numerical analysis of Raman measurements of the E2High mode. We vary the temperature to displace the resonance of the E2High mode along the ridge and detect a wide spectrum of the two‐phonon DOS in ZnO. We first derive the two‐phonon DOS by increasing the temperature from 300 K to 1000 K with a 20 K step. Next, we perform the same study but decrease the temperature from 1000 K to 300 K to observe how the two‐phonon DOS changes due to thermal annealing. The results show that lattice defects significantly enhance the two‐phonon DOS, which highlights the need for an effective thermal management strategy when ZnO lattice defects are harnessed for technology applications. [ABSTRACT FROM AUTHOR]

In this study, spin coating, which is a chemical film layer thin film deposition method, was used for coronene films that were grown on Si substrates annealed at 325, 350 and 375 K to examine the impacts on the optical properties of films. This method allows for easy control of the deposition parameters such as concentration, temperature and time as well as enables the film growth at low cost. Optical (UV–Vis) spectral measurements in the wavelength range from 200 nm to 800 nm were used to extract the bandgap information and to calculate various optical parameters of the spin-coated coronene films. The electronic transitions on the absorption of photons of suitable energy are of indirect allowed type. The corresponding optical bandgap ( E g ) was determined. Complex dielectric constants, dissipation factor, optical and electrical conductances and refractive index of coronene films were analyzed as a function of temperature. As the film annealing temperature was increased, the dielectric constants and the refractive index values increased, whereas the optical bandgap and electrical and optical conductivity values decreased. [ABSTRACT FROM AUTHOR]

This study explored the effects of annealing on the structural, optical, and semiconducting properties of hydrothermally derived CoS 2 nanoparticles and its impact on carrier transport through a Schottky junction ITO/CoS 2 /Al device. The current rectification ratio obtained from current–voltage measurements for CoS 2 (derived at room temperature) was 21.57 at a potential of ±1 V, but it was 70.61 for the Schottky junction fabricated by annealing (at 250 °C) with CoS 2. The ideality factor (n), series resistance (R s), barrier potential (φ b), and other parameters were determined for the devices. The ideality factor improved significantly to 1.34 for the sample, produced at 250 °C. The charge transport phenomenon was examined based on thermionic emission theory and related parameters, such as the mobility (of the order of 10−4 m2V−1s−1), carrier concentration (of the order of 1020 m−3), density of state (of the order of 1021 eV−1m−3), and transit time (of the order of 10−9s), were estimated by employing space charge limited conduction (SCLC) theory. The occurrence of free carriers gave rise to ferromagnetic behavior, which was also studied. This is the first study to investigate the relationship between the magnetic spin and electronic behavior of CoS 2 nanoparticles. The observed intrinsic ferromagnetism and magnetic behavior with respect to the temperature and magnetic field indicated the suitability of the material for spin-based electronic applications. Finally, the potential behavior of annealed (at 250 °C) CoS 2 in the ITO/CoS 2 /Al Schottky device was observed. [Display omitted] • Hydrothermal synthesis and characterizations of CoS 2 nanomaterial. • Derived CoS 2 annealed at 200 °C and 250 °C. • Successful fabrication of ITO/CoS 2 /Al Schottky device. • Annealed CoS 2 improves carrier transport behavior. • Studied magnetic behavior to check potentiality of materials in spintronic application. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) is attracting attention as a renewable energy source in various fields. However, H2 has a potential danger that it can easily cause a backfire or explosion owing to minor external factors. Therefore, H2 gas monitoring is significant, particularly near the lower explosive limit. Herein, tin dioxide (SnO2) thin films were annealed at different times. The as-obtained thin films were used as sensing materials for H2 gas. Here, the performance of the SnO2 thin film sensor was studied to understand the effect of annealing and operating temperature conditions of gas sensors to further improve their performance. The gas sensing properties exhibited by the 3-h annealed SnO2 thin film showed the highest response compared to the unannealed SnO2 thin film by approximately 1.5 times. The as-deposited SnO2 thin film showed a high response and fast response time to 5% H2 gas at 300 °C of 257.34% and 3 s, respectively.

WO3 Nanocrystalline thin films were prepared by Electron Beam Evaporation on cleaned glass substrates. The effect of annealing temperature on the structural, morphological, and optical properties of WO3 thin films has been studied. The single-phase monoclinic structure of the WO3 3 films has been confirmed by x-ray diffraction analysis, all films have homogenous morphology surfaces. The transmission of prepared films was measured in the wavelength range 300-900 nm. WO3 thin films show the indirect band gap ware decreased from about (3.193 eV) before annealing to about (3.061 eV) and (2.952 eV) after annealing. [ABSTRACT FROM AUTHOR]

We have investigated the effect of annealing conditions onto the cadmium telluride (CdTe) layers obtained using potentiostatic electrodeposition from non-aqueous electrolyte. A conventional three-electrode geometry consisting; working (FTO), counter (Platinum) and reference (Ag/AgCl) electrodes were employed. The samples electrodeposited at − 0.625 V were annealed at 420 °C and cooled down with different procedures. The samples were characterized to study the structural, optical, morphological, compositional and transport properties. Quenched sample is found better as compared to naturally cooled and as-deposited samples. Growth of cubic polycrystalline crystal structure with improved crystallinity of CdTe is revealed from annealed samples. Highly stoichiometric CdTe layers with densely packed globular surface morphology of particle size ~ 2 μm obtained upon annealing the samples is proposed to be suitable for high efficiency thin film solar cells (TFSCs). The micro-structural Raman analysis supports the increased crystallinity and stoichiometric growth of sample after annealing. Highly ohmic behavior with higher carrier concentration and ideality factor measured for quenched samples is reported to be associated to sink in grain boundaries due to grain growth results the densification of sample leads to less defective layers. The results imply that annealing conditions have significant impact on the properties of CdTe samples and the quenched films may be most appropriate as an absorber layer for TFSC applications. [ABSTRACT FROM AUTHOR]

The magnetocaloric (MC) properties of Ni0.5Cu0.25Zn0.25Fe2O4 (NCZFO) nanoferrite samples prepared under different annealing temperatures were simulated by phenomenological model. The results indicate that MC properties of NCZFO nanoferrites change none monotonically with annealing temperature. Furthermore, the range of temperatures between 407 and 515 K are suitable for NCZFO nanoferrites to be used as an effective material in magnetic refrigeration (MR). It is concluded that NCZFO nanoferrites are very practical MC materials in MR for high temperature applications like automotive, aerospace, and food industries. [ABSTRACT FROM AUTHOR]

Chalcogenide-based In2Se3 thin films were deposited by RF magnetron sputtering method at room temperature, and then were annealed at different temperature under nitrogen atmosphere in order to study the effect of annealing temperature on structure and optical. X-ray diffraction analysis show that, the preferred orientation in (110), (006), and (207) plane were observed in XRD result of the film sample annealed at 400°. The Raman spectrometer result reveals that the main Raman peaks were identified as the -phase In2Se3 structure and the peak in the film annealed at 400° moves to small direction indicates the inner structure changes occurrence. A Spectroscopic Ellipsometer was employed to measure the optical constants including refractive index and the extinction coefficient of the films. The optical bandgap decreased from 3.41 eV to 2.45 eV with the annealed temperature increasing. The variation is attributed to the Burstein-Moss effect. [ABSTRACT FROM AUTHOR]

Sn2Sb2S5 materials were synthesized by thermal evaporation using earth-abundant tin, antimony and sulfur elements. The effect of annealing temperature on structural, morphological, optical, thermal and electrical characterization was obtained using many techniques. The deposited films were annealed in air for 1 h at 100 °C and 300 °C. X-ray diffraction analysis reveals that while as-deposited films are amorphous, a crystallized phase, with an orthorhombic crystalline structure, appears after annealing. Via the photothermal deflection spectroscopy, the sub-bandgap energy decreased from 1.98 to 1.75 eV with rising the annealing temperature. Besides, static and dynamic thermal properties of as deposited and annealed Sn2Sb2S5 thin films were measured using electropyroelectric method. It was observed that an increase (40.5–46.5 W m−1 K−1) was found for the thermal conductivity values by increasing annealing temperature, while thermal diffusivity decreases from 12.1 × 10−6 to 9.31 × 10−6 m2 s−1. Moreover, Nyquist spectra performance in the temperature range 300–540 K revealed the presence of a relaxation phenomenon in the microstructure of the studied sample. In addition, the level of the peaks is crashed with temperature, showing that the charge carriers are thermally activated. Finally, Sn2Sb2S5 thin film annealed at 300 °C was found the best sample for use in optoelectronic and solar cell devices. This work suggests a low cost promising compound for scalable synthesis of Sn2Sb2S5 thin films for solar cell and photovoltaic applications. [ABSTRACT FROM AUTHOR]

Pb(Zrx,Ti1-x)O3 (PZT) powder was prepared via solid-state reaction and deposited on glass by Pulsed Laser Deposition (PLD). X-ray diffraction (XRD) analysis carried out to investigate the phase structure, it was found that PZT thin films with x=0.7 are polycrystalline with many peaks, and the results of Atomic Force Microscopy (AFM) used to studied the samples topographic indicated the film have grain size around 100 nm decrease to around 70 nm after annealing to 723 K. The optiical properties of PZT films with x=0.7 studied at RT and 723 K. The absorbance and transmittance spectra have been registered in the wavelength range (390-1100) nm so as to examine the optical properties at vis-IR wavelengths. It was investigated that the optical energy gap (Eg) increase when annealing temperature (Ta) increase. An extinction coefficient, refractive index, real and imaginary dielectric constant were sensitive to the change in temperature. Fourier Transform Infra-Red (FTIR) to know the identity and to study the vibrational frequencies between the bonds of atoms for synthesized (PZT) Nanoparticles which found stretching at (3477.66 cm-1) after annealing to 723 K. the interferometer used to determine the thickness of the deposited film, it found of about 200 nm.

Bipolar plates (BPs) are key component of a fuel cell and the high prices of fuel cell are owed to the use of expensive BPs. Metals are cheap alternate to the conventional thicker and expensive graphitic BP plates. Stainless steel (SS) is considered to be the most suitable future BP material but highly corrosive nature of metals prevents their direct use as BPs, so surface treatment is obligatory. Ti–Al–C is an important ternary metal carbide which possess various unique and useful properties and could be considered as an effective coating material for SS BPs. Since the film properties are sensitive to the substrate type, so a detailed investigation about the morphology and microstructure of Ti–Al–C films, deposited on two different substrates (SS304 and SS316) by a combined ECR-CVD and PVD system, as a function of annealing temperature is reported hereby. It was observed that change in microstructure is diverse for different substrates with annealing temperature. Moreover, the formation of Ti 2 AlC MAX phase along with other phases was also recognized at an annealing temperature of 700 °C. Our study provides an insight about the variation in morphology and microstructure of Ti–Al–C thin films on SS substrates with annealing temperature. • Stainless steel (SS) requires protective coating for fuel cell applications. • Ti–Al–C films are coated on SS304 and SS316 by a scale-able method. • Annealing temperature renders varied morphology and microstructure. [ABSTRACT FROM AUTHOR]

Au/SnO 2 quantum dots (AuSQDs) were synthesized, and the effects of annealing on their structural and optical properties were examined. Significant changes were observed in the bandgap and surface plasmon resonance (SPR) of the AuSQDs after thermal treatment at different temperatures (400, 500, and 600 °C). The properties of the as-prepared and annealed samples were characterized via X-ray diffraction analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy, and diffuse reflectance spectroscopy. Annealing reduced the bandgap from 3.03 to 2.33 eV and increased the crystallinity while maintaining an average crystallite size below 10 nm. XPS valence band (VB) profiles provided information regarding the VB edge potentials, which helped to determine the conduction band edge potentials. An enhancement in the SPR of the Au nanoparticles was observed for AuSQD-500, which had the smallest bandgap among the samples investigated. Image 1 • In-situ synthesized Au/SnO 2 quantum dots were obtained by a novel approach. • Au/SnO 2 quantum dots were thermally treated at different temperatures. • Improved crystallinity was observed for heat-treated Au/SnO 2 quantum dots. • Heat treatment tuned the bandgap of AuSQDs from 3.03 to 2.33 eV. • Surface plasmon resonance was enhanced by the heat treatment of Au/SnO 2 QDs. [ABSTRACT FROM AUTHOR]

Thin films of Co1−xTbx (x = 0.10, 0.12, and 0.15) alloy have been prepared by a co-sputtering process using dc magnetron sputtering. The measurement of temperature variation of magnetization indicates that these films exhibit ferrimagnetism with Curie temperature (TC) much above the room temperature. The M–T curves under zero-field-cooled and field-cooled conditions indicate that Co0.85Tb0.15 film exhibits non-collinear sperimagnetic ordering due to competition between exchange interaction and perpendicular magnetic anisotropy. An increase of coercivity, squareness, and change of magnetic isotropy to magnetic anisotropy behavior with the increase of Tb composition was observed. Particularly, Co0.85Tb0.15 is found to exhibit perpendicular magnetic anisotropy. The relative reversal in these films follows the Kondorsky model. The post-annealing of the films helps to improve the squareness of the hysteresis curve, but it reduces the coercivity. [ABSTRACT FROM AUTHOR]

In this work, the effect of annealing on Au-CuO films obtained by chemical bath deposition method was studied in terms of their structural, electrical and optical properties. Annealing process was carried out at an oxygen environment. The CuO peaks were detected using X-ray diffraction and all of the films were polycrystalline. Crystal size, preferential orientation, and surface tension were estimated from XRD data. The surface morphology and thickness of the films was determined using a field emission scanning electron microscope. Energy dispersive Xray analysis stated average atomic percentages of Au in the films. The electrical resistivity values of the films determined using four probe methods varied from 155.74 to 496.87 O.cm. The optical properties of the films were determined using the optic spectrometer. The energy band gap values, extinction coefficient, refractive index and dielectric coefficient of the films were also calculated. [ABSTRACT FROM AUTHOR]

Effect of annealing on microstructure, electrochemical, and magnetic properties of Co-doped SrTiO3 nanocubes obtained by the hydrothermal method was studied. X-ray diffraction (XRD) results of all as-prepared and annealed Co-doped SrTiO3 samples revealed a cubic perovskite structure with the second phases of SrCO3 and Co3O4in as-prepared and annealed SrTi0.90Co0.10O3 samples, respectively. Agglomerated nanocubes could be clearly observed in all as-prepared and annealed Co-doped samples by scanning electron microscope (SEM) and transmission electron microscope (TEM). X-ray absorption near edge spectroscopy (XANES) results suggested the presence of Co2+ cations in as-prepared Co-doped SrTiO3 samples, while both of Co2+ and Co3+ cations were found in annealed Co-doped SrTiO3 samples. The cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) results of as-prepared and annealed SrTi1-xCoxO3 (x = 0.05, 0.075 and 0.10) electrodes revealed pseudocapacitor behavior of the Faradaic redox reaction type. The specific capacitance (Csc) was affected by the increase of Co content in all as-prepared and annealed Co-doped SrTiO3 samples with an excellent cycling stability after 200 cycle test of 97.24% and the highest value of 75.28 F g−1 at 1 A g−1 in an annealed SrTi0.925Co0.075O3 electrode. Magnetization measurements at room temperature using vibrating sample magnetometer (VSM) revealed diamagnetic behavior of as-prepared SrTiO3 sample, whereas paramagnetic behavior was observed in all as-prepared Co-doped SrTiO3 samples. After annealing, undoped sample exhibited paramagnetic behavior, whereas ferromagnetic behavior was observed in all Co-doped SrTiO3 samples with the increase of saturation magnetization (Ms) at 10 kOe from 0.58 to 1.63 emu/g and the coercive field (Hc) from 43.71 to 123.87 Oe, suggested to originate from the face-center exchange (FCE) mechanism. [ABSTRACT FROM AUTHOR]

Hydrogenated silicon (Si:H) layers have been deposited on crystalline silicon substrate by radiofrequency plasma-enhanced chemical vapor deposition technique (rf-PECVD) from SiH4/H2 gas mixture using different deposition times and after a seed layer with thickness of 70 nm (to improve the nucleation of nanocrystallites). The effect of the deposition time on the as-deposited and annealed layers was investigated. Ultraviolet–visible–infrared (UV–Vis–IR) spectroscopy was used to determine the thickness of the layers. Before annealing, the layer thickness showed a linear variation with deposition time in the range from 450 s to 1500 s. On the other hand, for deposition times of 450 s, 600 s, and 1500 s, the layers showed an x-ray diffraction (XRD) peak corresponding to the (111) crystal plane of Si. Raman spectroscopy confirmed the appearance of the crystalline phase in these layers. Raman scattering studies showed that, when using the short deposition time for the top layer, the crystalline peak dominated. We deduce that insertion of a seed layer improves the crystallinity of the top layer. In addition, the crystallinity increased slightly with the deposition time. The structural properties of the layers annealed at 900°C were studied by Raman spectroscopy and XRD analysis. We noted an increase in the crystalline volume fraction and the appearance of (111) crystal plane of silicon, confirming the transition from amorphous to nanocrystalline phase for all the annealed films. [ABSTRACT FROM AUTHOR]

In this paper, we have examined the structural, microstructural, and magnetic properties of Er - Co - B compounds. High-energy ball milling has been used to homogeneous the stoichiometric mixture of Er, Co and B as starting materials to synthesis the Er 17 Co 75 B 8 powders. The samples are crystallized in the hexagonal CaCu 5 - structure type with P6/mmm space group. Their structural and magnetic properties were assumed systematically as a function of annealing temperature. The structural properties were studied by means of X-ray diffraction and the microstructural properties via Scanning Electron Microscopy. The magnetic phase with abbreviated formula ErCo 4.5 B 0.5 and global formula Er 16.67 Co 75 B 8.33 was a dominate phase. These compounds exhibit a high coercivity of 8 kOe at room temperature for ErCo 4.5 B 0.5 annealed at 1073 K for 1/2 h. These magnets with high H C are appropriate to permanent magnet applications. We have also applied to the Approach of Saturation in to Magnetization (ASM). The results were understood in according to the model of random magnetic anisotropy. Image 1 • Structural and magnetic properties of ErCo 4.5 B 0.5 alloys have been investigated. • The structural and magnetic properties vs annealing temperature (T a) were studied. • At 293 K, H C reaches its maximal value about 0.8T for T a = 1073 K. • The results were interpreted in the framework of random magnetic anisotropy model. • Some parameters were extracted such as the local magnetic anisotropy constant. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Amorphous copper phosphide OER catalyst is synthesized by one-step electrodeposition. • A smooth morphology with surface void is obtained after annealing. • An overpotential of 310 mV at 10 mA/cm2 with a Tafel slope of 88 mV/dec is demonstrated. • Excellent long-term electrochemical durability is observed. Abstract A copper phosphide (Cu 3 P) thin film is synthesized on a Ni foam using a one-step electrodeposition method at room temperature and annealed at 300 °C in Ar atmosphere. The Cu 3 P film is amorphous and has a flat morphology with surface voids. It works as an electrocatalyst for water oxidation in an alkaline 1 M KOH electrolyte. It exhibits excellent catalytic oxygen evolution reaction with an overpotential of 310 mV, Tafel slope of 88 mV/dec, and good stability over 20 h of operation at 10 mA/cm2. The excellent OER performance is due to its large electrochemically active surface area and low charge transfer resistance at the catalyst-electrolyte interface after the annealing. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) films doped with 10 wt.% of yttrium chloride (YCl 3) have been made by casting from their aqueous solutions. The structure of un-annealed and annealed PVA-YCl3 films was studied using X-ray diffraction (XRD) patterns and Fourier-transform infrared spectroscopy (FTIR). Both FTIR and XRD revealed that the crystalline ratio of the studied samples increased due to the effect of annealing. The effect of annealing on the optical properties has been studied. Dispersion of the refractive index was described using the single oscillator model. The single oscillator energy and the dispersion energy were estimated. The calculated optical band gap of all PVA-YCl3 films was 5.0 eV. The behavior of ac conductivity showed that the conduction mechanism of PVA-YCl3 films was correlated barrier hopping model. The dielectric constant and dielectric loss index were decreased with the increase of the field frequency. The electric modulus granted a straightforward technique for assessing the dielectric relaxation time. The calculated activation energy obtained from the electric modulus mechanism was 0.172 eV. [ABSTRACT FROM AUTHOR]

The article investigates the annealing process of bipolar transistors after total dose irradiation, using the GLPNP transistor as the research object. After total dose irradiation, room temperature and high temperature annealing tests were carried out. Gummel curve, GS curve and SS curve of bipolar transistor are obtained by I/V scanning, gate scanning and sub-threshold scanning. The evolution behavior of radiation-induced oxide trap charges and interface state damage defects during annealing of bipolar transistors at different temperatures was quantitatively analyzed by different microscopic defect characterization methods. Generally speaking, this study is of great significance to better understand the recovery mechanism of electrical properties of bipolar transistors during annealing after total dose irradiation, and can provide reference for the design, application and radiation-hard of transistors. • The annealing process of transistor after TID was studied by using different microscopic defect characterization methods. • The radiation-induced oxide trap charges and interface state damage defects during annealing are quantitatively analyzed. • The change trend of defects density at different annealing temperatures is compared through Lots of experimental data. • The influence of microscopic defects on the macroscopic electrical parameters of bipolar transistor is analyzed. [ABSTRACT FROM AUTHOR]

In this investigation, Ni47Mn40Sn13 ferromagnetic shape memory alloy was prepared by mechanical alloying. The metal powders were ball milled in argon atmosphere for 20 hours. X-ray diffraction pattern confirmed formation of crystalline structure of Heusler alloy. As-milled powder samples were sealed in quartz tubes under high vacuum and subjected to heat treatments at 950°C for different time durations. Then, the effect of isothermal ageing on structural, magnetic and electrical properties of samples was investigated. Results of electrical resistance displayed a metal-like behavior around martensitic transformation. The results showed that 16 hours of annealing was the optimal time for producing this alloy which could be an appropriate candidate for magnetic refrigerant.

Highlights • X-ray diffraction analysis revealed the formation of Sn x Sb 2 S y (1 ≤ x ≤ 3, 4 ≤ y ≤ 6) sulfosalts thin films. • The films have strong diffraction peaks at 2θ = 31.65°, 31.67° and 31.58° for SnSb 2 S 4 , Sn 2 Sb 2 S 5 , and Sn 3 Sb 2 S 6 , respectively. • Thermal conductivity values are from 30.4 Wm−1 K−1 to 79.2 Wm−1 K−1. • The thermal diffusivity values are from 4.20 10−6 m2s-1 to 20.5 10−6 m2s-1. • The SnSb 2 S 4 thin film annealed at 200 °C is a good candidate for solar cell application. Abstract SnSb 2 S 4 , Sn 2 Sb 2 S 5 and Sn 3 Sb 2 S 6 thin films were obtained by a vacuum thermal evaporation method. The films were thermally annealed at 200 °C in tube furnace. Their structural and thermal properties are studied by X-ray diffraction and electro-pyroelectric technique. The X-ray diffraction analysis revealed that the polycrystalline Sn x Sb 2 S y films were successfully obtained using an annealing temperature of 200 °C. The thermal measurements show that these thin films have thermal conductivity ranging from 30.4 to 79.2 Wm−1 K−1 and the highest value belongs to film of SnSb 2 S 4 material annealed at 200 °C. Also, It is found that Sn x Sb 2 S y films exhibit thermal diffusivity values situated in (4.20–20.5)10-6 m2s-1 domain. The most significant result of the present study is that SnSb 2 S 4 thin film annealed at 200 °C seems a good candidate for solar cell application. [ABSTRACT FROM AUTHOR]