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In this work, we have successfully prepared the nano-coral to be intact with the mesoporous of Sn-HfO2 thin films through the (jet nebulizer spray pyrolysis) JNSP technique from different Sn (5, 10, 15 Wt.%) to improve the MIS Schottky diode Al/Sn-HfO2/n-Si. To achieve the phase transformations (monoclinic to orthorhombic) in pure hafnium oxide thin films, we have added the Sn ions as the composite at optimized temperature 600 °C. The XRD characteristic used to determine the structural parameters such as the phase, grain size for pure HfO2, and composite Sn-HfO2 films. The mesoporous with irregularly shaped balls and nano coral-like morphology have been observed through FESEM images. The absorption coefficients and bandgap energy have been determined from the UV Vis spectrum. The EDAX elementary analysis has confirmed the presence of Sn, Hf, O elements in each film. The XPS spectrum has confirmed Sn's presence and binding peak with a spin-orbit on the films' surface. I-V curves of forward and reverse bias determine the barrier height, ideality factor, and saturation currents from the thermionic emission theory. All the Al/Sn@HfO2/n-Si diode parameters are strongly improved after the incorporation of Sn ions. [ABSTRACT FROM AUTHOR]

In this work, pure and Mn-doped nickel ferrite (Ni1-xMnxFe2O4, x = 0, 3, 6, 9, and 12 wt%) thin films were prepared using facile nebulizer spray pyrolysis technique. The effect of Mn concentration on the structural, optical, and magnetic properties was studied. The XRD pattern confirms the cubic spinel structure of Ni1-xMnxFe2O4 thin films and reveals the preferred orientation along the (311) direction for each film. Moreover, the average crystallite size (D) is found to increase from 13 to 30 nm with increasing Mn concentration. The FESEM micrographs exhibit randomly arranged plate-like and rice-like grains. The elements such as Mn, Ni, Fe, and O are confirmed by the EDX analysis. The optical band gap energy (Eg) varies between 2.90 and 3.60 eV. The Ni1-xMnxFe2O4 film prepared with 3 wt% of Mn exhibits superior ferrimagnetic behavior with the highest value of ηB (57.31) due to the high crystallinity, packing density, and smooth surface of the film. The present work shows that the facile nebulizer spray pyrolysis technique can produce high-quality Ni1-xMnxFe2O4 thin films with good magnetic properties. [ABSTRACT FROM AUTHOR]

Zn-doped TiO2 films were deposited on ultrasonically treated alumina substrates via the automatic nebulizer spray pyrolysis method. In this study, the thickness of the as-prepared films was gradually reduced, and their Brunauer–Emmett–Teller (BET) surface area and pore volume results were notably improved; in addition, values for the blue-shifted sharp edge absorption with an enlarged bandgap (Eg) were revealed in the deposited films. The agglomerated granular form has evolved into tiny grains with porous brighter particles scattered over the surface of the coated films. The sensing performance to reducing gases for combustible gas of ammonia (NH3) and volatile organic compounds of methanol (CH4O) and formaldehyde (HCHO) with the function of operating temperature and gas concentration were studied, and the highest sensing response of the hazardous formaldehyde (HCHO) reducing gas was noticed. [ABSTRACT FROM AUTHOR]

In this work, we report a p-Si/n-CeO2 junction diode fabricated by a cost-effective and large-area deposition technique of jet nebulizer spray pyrolysis. The n-CeO2 layer was coated on four different substrate temperatures (Tsub) 350, 400, 450, 500 °C and their properties were studied by various techniques like XRD, FE-SEM with EDX, UV–Vis and I–V characterization. XRD pattern confirmed a cubic fluorite crystalline phase of CeO2 thin films with preferential growth along (2 0 0) direction. A smooth surface with inter-connected smaller grains was recorded by FE-SEM micrographs and also the existing elements Ce and O have been confirmed. For Tsub of 450 °C, an exceptional optical absorption with smaller band energy of 3.3 eV was recorded in the UV–Vis spectrum. The electrical conductivity results indicated that all the films are semiconducting in nature. I–V characteristics of all the fabricated diode showed better rectification in dark with excellent photovoltaic characteristics under light exposed condition. The photosensitvity of the diode varied from 21.94 to 1093.75% with substrate temperature. Our results strongly suggested that rare-earth based p-Si/n-CeO2 diodes are suitable for future applications in ultraviolet photo-detector and photo-diode. [ABSTRACT FROM AUTHOR]

Inter-connected network grains of tungsten trioxide (WO3) thin films were deposited on glass using a jet nebulizer spray pyrolysis (JNSP) technique by varying the substrate temperature at 350, 400, 450 and 500 °C. Phase transformation (monoclinic to orthorhombic) was observed during the film growth through X-ray diffraction (XRD) analysis. Field emission scanning electron microscope (FE-SEM) images revealed a better grain growth with smooth surface for 400 °C. The WO3 film deposited at 400 °C exhibits minimum band gap and maximum optical conductivity of 3.2 eV and 5.8 × 1014 (Ω.cm)−1. From the current-voltage (I–V) characteristics, the mean electrical conductivity is found to increase gradually and the activation energy reduced at higher substrate temperature. Cu/WO3/p–Si structured Schottky barrier diodes (SBDs) have been fabricated with different substrate temperature and it was tested under variable device temperatures ranging from 30 to 170 °C. The experimental results of all SBDs indicated a linear reduction in the ideality factor (n) with a small increment in effective barrier height (ΦB) with increase in device temperature, which is due to lateral inhomogeneity's at the interface. Moreover, the minimum n value of 2.89 and their corresponding ΦB of 0.71 eV were recorded for device temperature at 170 °C. Compared with other SBDs, the device fabricated at 400 °C demonstrated a better thermal stability and device performance. [ABSTRACT FROM AUTHOR]

The effect of variant high boiling point solvent combinations in the synthesis and photo-sensing characteristics of tin disulfide (SnS2) thin nanosheets were investigated. Solvent dependent single-phase formation was observed by powder X-ray diffractometry (XRD), and results were verified with Raman spectroscopy measurements. Particles synthesized with only oleylamine show a mixed-phase, and two other solvent combinations such as oleylamine + oleic acid + n-octadecene, and oleylamine + oleic acid, show single-phase 2H–SnS2, without phase contamination. Scanning and transmission electron microscopes were used to verify the orbicular and hexagonal shape of synthesized SnS2 nanosheets. Well-characterized samples were employed to fabricate heterojunction photosensitive diodes using a p-type silicon substrate. Light-responsive measurement results of fabricated diodes indicate that the oleylamine + oleic acid synthesized sample show very high light-sensitivity, and the fill factor value of a fabricated diode is closer to the ideal diode. [ABSTRACT FROM AUTHOR]

In this paper, we report the influence of thermal annealing on structural, electrical properties V2O5 thin films and their application of SBD's. V2O5 thin films were prepared using glass substrate by sol gel spin coating technique. Films were annealed at different temperatures such as 300 °C, 400 °C and 500 °C. The prepared films were introduced as an interfacial layer between metal and semiconductor interface. V2O5 films exhibit single phase tetragonal structure and surface morphology interestingly, it was changed into nanorod-like structure at higher annealing temperature which was observed through field emission scanning electron microscopy. Atomic force microscopy reveals the surface roughness and the mentioned roughness is increasing due to the increase of annealing temperature. The elemental composition was confirmed by energy dispersive X-ray spectrum. From UV–Vis absorption spectroscopy results revealed that the band gap shows a decreasing trend on increasing the annealing temperature. Besides, we analyzed the influence of high quality vanadium pentoxide (V2O5) thin films prepared at different annealed temperatures and act as an interfacial layer between metal and semiconductor in the fabrication of Schottky diode. V2O5 films depicts high electrical conductivity (σdc) of 0.945 (S cm−1) with activation energy of 0.0747 eV (Ea) as a function of temperature. The MIS structured Cu/V2O5/n-Si based SBD's diode performance was analyzed for different temperatures ranging from 30 to 150 °C. V2O5 thin-film act as an interfacial layer on Cu/V2O5/n-Si Schottky diode was successfully explained by the thermionic emission theory. [ABSTRACT FROM AUTHOR]

Tungsten disulfide (WS2) thin films were deposited on the glass substrate by varying its temperature from 350 to 500 °C using jet nebulizer spray pyrolysis (JNSP) technique. The WS2 thin films were characterized through various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray analysis (EDX), UV-Visible spectroscopy (UV), photoluminescence (PL), Hall measurements and current-voltage (I-V) characteristics. XRD pattern revealed that the prepared WS2 films are polycrystalline in nature with rhombohedral and hexagonal crystal structures. The average crystallite size of WS2 thin films changed from 52.23 to 47.40 nm. SEM images showed the uniform grain size, which is agglomerated at the higher substrate temperature. The presence of elements like W and S was confirmed through EDX spectrum. From UV analysis, the minimum optical band gap and maximum absorption was obtained for the film deposited at 450 °C. The WS2 thin films exhibited an n-type semiconductor nature with the carrier concentration of 1014 cm−3, which was demonstrated through hall measurements. Also, the electrical resistivity of the WS2 films varied from 3.26 × 105 to 1.59 × 107 Ω cm. The p-Si/n-WS2 junction diode was fabricated with various substrate temperature of (350-500 °C). Junction diode parameters like ideality factor (n), barrier height (ϕB) and reverse saturation current (Io) values were calculated and interpreted based on the thermionic emission theory model. [ABSTRACT FROM AUTHOR]

Metal–insulator–semiconductor (MIS) structure of Cu/Zr–WOx/p-Si Schottky diodes with different concentrations (0, 4 and 8 wt%) of Zr content were fabricated. The interfacial layer of zirconium–tungsten oxide (Zr–WOx) film was grown on p-type silicon (p-Si) wafer using jet nebulizer spray pyrolysis (JNSP) technique at the substrate temperature of 400 °C. After that, the Cu electrode was coated on the Zr–WOx film via vacuum deposition method. The multiphase (orthorhombic and cubic) crystal structures of Zr–WOx were revealed by X-ray diffraction (XRD) pattern. The surface morphological analysis using scanning electron microscope (SEM) showed the dissimilar structures of surface and energy dispersive X-ray diffraction (EDX) confirmed the presence of W, Zr and O atoms. Using UV–Visible (UV–Vis) and DC elecrical (I–V) analysis, the minimum band gap energy and average conductivity were obtained for higher concentration (8 wt%) of Zr content. The minimum barrier height (ΦB) and minimum ideality factor (n) values were attained for 4 wt% of Cu/Zr–WOx/p-Si Schottky barrier diode (SBD) under illumination condition. [ABSTRACT FROM AUTHOR]

In this work, boron doped graphene nanoparticles (NPs) were synthesized by the hydrothermal route with different boron tribromide concentrations such as 52, 104, and 156 μL. The structural, morphological and optical properties of the prepared NPs were studied using different characterization techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), atomic force microscopy (AFM), UV–vis spectroscopy and photoluminescence spectroscopy (PL). The XRD pattern reveals the hexagonal crystal structure. The SEM image showed textured sheet-like layers which got agglomerated to form fluffy structures. The TEM images recorded single-crystalline nature and also confirms the particle size was reduced upon increasing boron tribromide solution concentration with recognizable particle shape. The topographic properties of the synthesized B-doped graphene NPs were also studied through AFM images. The UV visible absorbance characteristics peaks 243 and 372 nm were observed correspond to π – π* in C–C bands and n- π* transition. After that as grown NPs were used to fabricate diode junctions on p-Si substrates (p-Si/n-B-doped graphene). The electrical performance of each p-Si/n-B-doped graphene diodes junction was examined using I–V characteristics and electrical parameters of diode junction such as ideality factor, barrier height and reverse saturation current were found 2.9–4.3, 0.75–0.83 eV and 4.88 × 10−6-7.26 × 10−6 A. The calculated ideality factor values of the p-Si/n-B-doped graphene diodes are decreased with increase in boron tribromide solution concentration. [Display omitted] • Boron doped graphene nanoparticles were synthesized by the hydrothermal route for various concentrations of Boron tribromide. • XRD pattern exhibited a hexagonal crystal structure with sharp crystalline peak at (002) orientation. • A sheet-like surface morphology was observed through SEM image. • TEM images confirm the particle size was reduced upon increasing boron tribromide. • A minimum ideality factor of n = 2.9 was obtained for p-Si/n-B-doped Graphene diode fabricated with 156 μL. [ABSTRACT FROM AUTHOR]

We report a novel highly sensitive and pseudocapacitive transparent nickel oxide (NiO) thin film based electrode material fabricated on a conductive glass substrate using a facile binderless electrodeposition process. Effect of the incorporation of Mo-dopant ion on some surface structural and electrochemical properties of the electrode was examined for high performance optoelectronic and charge storage potentials. The material showed some uniqueness in some microstructural features and enhanced degree of crystallinity, suitable for charge extraction and transport with Mo doping. The deposited NiO film demonstrated red shift in band structure by exhibiting optical band gap narrowing from 3.88 to 3.61 eV with increasing Mo content. The degree of disorder as revealed from Urbach response of NiO film was found varying with Mo-content. The material also exhibited enhanced Ni2+ electronic transition states with increasing Mo content which quenched at a critical dopant concentration of 2.4 %. The fabricated NiO thin film electrode showed increased supercapacitive specific capacitance and areal capacity up to a peak value of 1412 Fg−1 and 101 mAh m−2 for 3 % Mo dopant content at 5 mVs−1 scan rate and 0.5 mA cm−2, respectively, but returned diminished at higher dopant content. Excellent cycling stability at ∼ 85 % after 5000 cycles, was also exhibited. Impedance spectroscopic features of Mo-doped NiO electrode indicated fast electrolytic ion transfer response with high rate charge storage capability. The study presents successful fabrication of Mo-modified NiO nanostructured electrode film and demonstrated the influence of Mo impurity on tailoring the properties of NiO host film as suitable electrode in high performance photocatalytic and supercapacitor devices. • Novel Pseudocapacitive Mo doped NiO Thin Film Electrode has been developed from simple two-electrode electrofabrication process • Microstructural studies revealed stoichiometric bunsenite NiO rock salt with fcc crystal structure. • Comparative electrochemical properties of NiO and Mo-doped Mo x O films as supercapacitive electrodes were examined. • The film demonstrated highly stable pseudocapacitive response with improved specific capacitance of 1412 Fg−1 and areal capacity of 101 mAh m−2 at 3% volume Mo dopant content. • The study showed that supercapacitive and photocatalytic properties of NiO thin electrode can be tailored by simply introducing Mo dopant impurity. [ABSTRACT FROM AUTHOR]

In this work, fine nickel oxide nanoparticles (NiO NPs) were successfully made utilizing a straightforward co-precipitation approach at low temperature. The effects of precursor concentration on the structural, optical, and electrical characteristics of NiO nanoparticles were investigated. All indexed diffraction peaks in XRD demonstrate the production of NiO with cubic structure. An increase in NiO crystallite size above 16.8 nm was observed when the precursor concentration exceeds 2 M, suggesting the presence of nanostructure in the final product. In FT-Raman spectra, the band centered at ∼ 500 cm–1 is due to Ni-O stretching (LO) mode, and two-magnon (2 M) scattering mode causes the band at 1514 cm–1. The synthesized product is composed of almost rod-shaped particles with a size range of 10–20 nm, according to FESEM pictures. The UV absorption studies showed a high absorption at the fundamental absorption edges originating at 332 nm, which gradually shifted to a lower energy region up to 400 nm with increasing precursor concentration, which means a reduction in bandgap values. The effect of precursor concentration associated with the electrical characteristics of the produced NiO nanoparticles has been investigated for the temperature range 30 to 130 °C. The I-V characterization was used to compute the different photo-diode parameters including n, Ф B , I o , P S , R, QE, and D*. The remarkable high photosensitivity of 1100% and specific detectivity of 4.324 × 10−10 Jones for the diode evaluated at 120 mW/cm2 was observed in a 2 M fabricated diode. These findings imply that all the fabricated diodes are exceptionally light-sensitive and are well-suited for upcoming UV photodetector applications. [Display omitted] • Development of NiO nanostructures-based photodiode with remarkable photosensitivity is reported • The XRD and Raman analyses confirm the synthesis of cubic NiO system • Crystallite size was improved from 10 to 17 nm with an increase in molar concentrations • Rising concentrations cause a steady decrease in the band gap energy from 3.45 to 3.1 eV. • A remarkably high photosensitivity of 1100% was observed for the device developed with 2 M concentration. [ABSTRACT FROM AUTHOR]

An effective heterojunction with robust charge separation and enormous degradation efficiency is the major task for photocatalyst preparation. In this study, we have prepared the FeCo 2 O 4 -loaded g-C 3 N 4 nanosheet by the sol-gel-assisted calcination method for photo-Fenton-like degradation under visible-light irradiation by activating persulfate. The nanocomposite exhibits a higher charge separation efficiency than pure g-C 3 N 4 and FeCo 2 O 4 for the degradation reaction against naproxen drugs. An effective interaction between the nanoparticles increases the degradation efficiency up to 91% with a synergistic index of 73.62%. Moreover, the nanocomposite exhibits a 78% mineralization efficiency against the naproxen pollutant under visible-light irradiation. For practical implementation, the degradation reaction was tested with various pH values, different water sources (DI, lake, and tap water), and light sources (LED (visible)/direct sunlight (UV-visible)). Moreover, the possible degradation mechanism predicted by the elemental trapping experiment and the recycling experiment clearly revealed that the heterojunction composite has a high enough degradation stability., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)