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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]

Pure CeO2 and Ni-doped cerium oxide (NDC) films were deposited by a facile and economic jet nebulizer spray pyrolysis (JNSP) process at 450 ºC substrate temperature. Here, efforts have been done to enhance the performance of the NDC diode using various doping concentrations of Ni (0, 2, 4, and 6 wt%). X-ray diffraction revealed polycrystalline film formation with a cubic crystal structure and the crystallite size of CeO2 was increased from 10 to 21 nm on Ni doping. EDX study confirms the presence of Ni in NDC films. FESEM explicitly shows fine spherical grains-like morphology. The optical studies indicate the reduction in the bandgap of CeO2 from 3.30 to 2.86 eV on Ni doping. The Photoluminescence (PL) spectrum proves that the oxygen vacancy is created in the CeO2 thin films while doping with Ni which leads to the blue shift and intensity enhancement of emission peak. NDC film prepared with 6 wt% showed a higher electrical conductivity ~ 3.76 × 10–10 S/cm which indicates that it is suitable for photodiode fabrication. The fabricated p-Si/n-NDC photodiode works with superior parameters like ideality factor (n) and barrier height (ΦB) under dark and illuminated conditions. The saturation current (Io) of the p-Si/n-NDC diode is varied from ~ 2.69 × 10–05 to 6.57 × 10–04 A with Ni concentrations. The estimated n and ΦB values of the p-Si/n-NDC junction diode are found to be decreased from 7.6 to 2.5 and 0.72 to 0.60 eV. These outcomes indicate that the fabricated photodiode is a useful element in optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this work, we present the synthesis and characterization of molybdenum oxide (MoO3) nanoparticles (NPs). The MoO3 NPs were coated on silicon (Si) wafer to fabricate n-MoO3/p-Si diode by the spin coating method. X-ray diffraction (XRD) profiles clearly show the crystalline nature of all specimens with an orthorhombic crystal system. Stretching and bending vibrations of molybdenum-oxygen were confirmed by the Fourier transform infrared analysis. The maximum absorbance was observed for MoO3 NPs prepared from Nitric acid (HNO3). Nano flakes like morphology were seen by scanning electron microscopy (SEM), and elemental dispersion spectral analysis approved expected Mo and O elements in the final product. Transmission electron microscopy (TEM) analysis of the as-prepared samples indicates a single-phase orthorhombic crystal structure. Electrical conductivity results show that synthesized samples are having semiconducting behavior. It is noted that the p–n junction diode prepared with Hydrochloric acid (HCl) has better rectifying behavior with lower ideal factor (n) values of 2.47 than the other sample. [ABSTRACT FROM AUTHOR]

The presence of carcinogenic dyes in industrial wastewater is a serious problem that hazards the water bodies and nano-catalysts are key members that are used to purify it. Therefore, this work investigates the synthesis of tungsten oxide (WO3) nanoparticles with various annealing temperatures in the range of 100–600 °C by the co-precipitation method for photocatalysis applications. The improvement in crystallinity of the nanoparticles achieved through annealing temperature and the crystallite size was an increase from 10 to 34 nm. The structural parameters of the prepared samples were characterized using XRD reveals the formation of stable monoclinic structure. FESEM morphological images confirmed the formation of irregularly shaped nanoplates. HRTEM and SAED patterns confirmed the growth of nanocrystalline WO3 nanoparticles. Parameters like (hkl) planes and interplanar spacing values obtained from HRTEM studies agreed well with the results of XRD. The elemental presence and chemical compositions were confirmed from EDS and XPS studies, respectively. The presence of functional groups has been verified through FTIR spectroscopy studies. Considerable decrements in the energy gap of WO3 NPs were observed with annealing from 2.89 to 2.61 eV. The defects/oxygen deficiencies were examined through photoluminescence. The photocatalytic performance of WO3 NPs was assessed by degrading the methylene blue dye. The parameters obtained from Pseudo first-order kinetic studies confirmed that 600 °C annealed WO3 NPs have higher photocatalytic activity. [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]

Octahedral indium oxide thin films with different precursor concentrations of 0.05, 0.075, 0.1 and 0.125 M were coated on glass substrates at 450 °C using jet nebulizer spray pyrolysis technique. Surface morphology of the prepared samples showed closely packed octahedrons for all concentrations. The measured root-mean-square value of the films was varied between 40.45 and 188.98 nm with increased precursor concentrations. From optical analysis, the calculated optical band gap was continuously decreased with increase in precursor concentrations. A slight blue shift was recorded through the PL spectrum while increasing the precursor concentration due to the oxygen vacancies. The nature of electrical conductivity of the In2O3 films was analysed. Interestingly, we have calculated two types of activation energies in the In2O3 films one is corresponding to low temperature and another is higher temperature. Further, p-Si/n-In2O3 junction diodes are fabricated with different precursor concentrations. Particularly, the 0.075 M of p-Si/n-In2O3 junction diode recorded a minimum ideality factor of n = 2.64 under light exposed condition, confirming the photo-conducting nature of the diodes in visible wavelength range. [ABSTRACT FROM AUTHOR]

Monoclinic WO3-nanoplate arrays have been effectively deposited via simple jet nebulizer spray pyrolysis technique at an optimized substrate temperature of 400 °C. These WO3-nanoplate arrays were used as an insulating layer in the metal–insulator–semiconductor (MIS) structure based Schottky barrier diodes. The effect of WO3 mol concentration during the deposition process was systematically interpreted with respect to the structural, morphological, optical and electrical properties of WO3-nanoplate array films. XRD pattern exposed the polycrystalline nature of the prepared films with a monoclinic phase. At higher concentration of 0.25 M WO3-nanoplates were firmly interconnected together and has been analyzed by a FE-SEM. From UV–Vis spectroscopy, the band gap values of the WO3 were found to vary from 3.2 to 3.4 eV with mole concentrations. DC electrical study recorded a steep increase in the electrical conductivity for the film prepared with 0.2 M of WO3. Notably, all the diodes exhibited positive photoresponse under illumination. Particularly, the MIS diode fabricated with 0.2 M revealed higher photoresponsivity and sensitivity of 960.85% and 33.40 mA W−1 respectively. [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]