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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]

The influence of nickel (Ni) doping concentrations on structural, optical, electrical and diode properties of molybdenum trioxide (MoO3) thin films has been studied systematically. Ni-doped MoO3 films and diodes were prepared for various doping concentrations of Ni such as 0, 3, 6 and 9 wt.% by jet nebulizer spray (JNS) pyrolysis technique. The structural properties of Ni-doped MoO3 films were analyzed by X-ray diffraction (XRD) pattern and scanning electron microscopy (SEM). The prepared films were exhibited in the orthorhombic crystal structure and sub-microsized plate-like surface morphology. The energy-dispersive X-ray spectroscopy (EDX) analysis confirmed the presence of Ni, Mo and O elements in the prepared films. Ultraviolet–visible (UV–vis) analysis results showed that the absorbance decreases with the increasing of Ni doping concentration and the minimum band gap energy (Eg = 2.25) was obtained for 9 wt.% Ni-doped MoO3 film. From current–voltage (I–V) characterization, the conductivity is increased by increasing the Ni doping concentration in MoO3 thin films. The diode measurements were performed in darkness and under light illumination of a halogen lamp. The methods of I–V, Cheung's and Norde were used to calculate the diode parameters of ideality factor (n), barrier height (Φb) and sheet resistance (Rs). Also, the light ON/OFF switching response of the fabricated n-NiMoO3/p-Si diodes was analyzed. [ABSTRACT FROM AUTHOR]

• Undoped and Sn doped Co 3 O 4 thin films were prepared by JNSP method. • Spherical-like grains are observed from the FE-SEM images. • The optical band gap of Co 3 O 4 film is noticed to be increased after adding Sn ions. • We have fabricated an undoped and Sn doped p-Co 3 O 4 /n-Si junction diode for various concentrations. • We observed that the p-Sn@Co 3 O 4 /n-Si diodes are highly sensitive and appropriate for photodetection applications. [Display omitted] In this work, we have prepared Co 3 O 4 thin films for different doping level including 0, 2, 4, and 6 wt% by JNSP method and analyzed their structural, morphological, optical, and electrical properties by XRD, FE-SEM, EDX, UV-Vis, and current-voltage (I-V) characteristics. The XRD profiles confirm the cubic crystal structures of Sn doped Co 3 O 4 films. Spherical-like grains are observed from the FE-SEM images and were suppressed due to Sn doping. Also, the elements like Sn, Co, and O were confirmed by EDX analysis. The optical band gap of Co 3 O 4 film is noticed to be increased after adding Sn ions, which has been studied through UV-Vis spectroscopy. Most importantly, we have fabricated an undoped and Sn doped p-Co 3 O 4 /n-Si junction diode for various concentrations. The determined ideality factor of the p-Sn doped Co 3 O 4 /n-Si diodes were reduced for both under dark and light conditions. In addition, the calculated responsivity, quantum efficiency, and specific detectivity of the diodes were enhanced with forwarded voltage. The p-Sn@Co 3 O 4 /n-Si diode fabricated with 2 wt% was achieved maximum responsivity and quantum efficiency of R = 247.03 mA/W, QE = 95.7%, and D* = 2.84 × 1010 at 3 V. We observed that the p-Sn doped Co 3 O 4 /n-Si diodes are highly sensitive and appropriate for photo-detection applications. [ABSTRACT FROM AUTHOR]

In this study, novel Gadolinium doped WO 3 nanorods (Gd@WO 3 NRs) were synthesized via facile hydrothermal method. The Gd@WO 3 NRs were systematically characterized by XRD, RAMAN, FESEM, XPS, UV–Vis, and PL. XRD profiles confirmed the single phase of WO 3, and the average crystallite size decreased with increasing the doping concentration. From EDS and XPS analysis of Gd@WO 3 NRs, the presence of Gd, W, and O were confirmed without any additional peaks. UV–Vis spectra indicated that the position of the absorption edge lies within the visible region at all Gd contents in WO 3, and the energy gap was studied. The photoluminescence test indicates that the 5 wt% of Gd doping in WO 3 could reduce the photogenerated electron-hole pair recombination. The remarkable enhancement in the photodegradation activity for degrading the Rhodamine B under visible-light irradiation of WO 3 was studied with Gd doping. The highest photocatalytic performance was found with 5 wt% Gd@WO 3 NRs, due to the accelerated charge transfer process, which improved the photogenerated electron-hole pairs separation. According to trapping studies, the possible photocatalytic mechanism of Gd@WO 3 NRs was also disclosed. The recycling test confirmed the stability of photocatalyst after three cycles. This novel Gd@WO 3 NRs proved to be a superior catalyst for the reduction of organic pollutants. [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]

• A polycrystalline with dual phase in nature of cubic and monoclinic structure was observed. • The largest and lowest energy gap values are found to be 4.03 eV and 2.44 eV for Gd and metal copper. • White sponge, nanorods, nanoneedles and nanorice shaped morphology has observed by FESEM. • The MIS diode was achieved a minimum ideality factor values of 5.34. • The excellent opto-electronics properties of the developed photodetectors make it suitable for future nano-electronics. Here we are reporting the development of Gadolinium based copper oxide nanocomposites via a cost-effective low-temperature co-precipitation process. X-ray diffraction study approves the dual phase polycrystalline cubic and monoclinic structure with predominant orientations along (2 2 2) and (0 0 2) directions. A strong &sharp peak is positioned at ~512 cm−1in FT-IR is assigned to metal oxide (Cu-O/Gd-O) network terminal stretching & phonon band. Absorption study reveals strong absorption peaks for the samples prepared from pure copper (Cu) and gadolinium (Gd), however poor absorption was noticed from mixed CuO-Gd2O 3 nanocomposites.The largest and lowest energy gap values are found to be 4.03 eV and 2.44 eV for Gd and metal copper, respectively. White sponge, nanorods, nanoneedles and nanorice shaped morphology has observed from FESEM analysis. X-ray photoelectron spectroscopy (XPS) survey spectrum unveils the essential elements like Cu, Gd and oxygen. The peak fitting of Gd4d exhibits two major peaks at 143.6 and 155.8 eV binding energies correspond to spin orbit doublet splitting of 12.2 eV between 4d 5/2 and 4d 3/2 , respectively. From I-V study, we observed that the presence of CuO-Gd 2 O 3 nanocomposites at p-Si/Al interface improved the performance of the MIS diode. The excellent opto-electronics properties of the developed photo-detectors make it suitable for future nano-electronics. [ABSTRACT FROM AUTHOR]

Herein, we are presenting the synthesis of pure WO 3 nanoparticles (NPs) and WO 3 /NiWO 4 nanocomposites (NCs) with improved photocatalytic activities via a simple co-precipitation process. Structural, morphological, and compositional studies approved the synthesis of the nanocomposite. Furthermore, XPS analysis confirm the chemical composition and incorporation of Ni in the final products. The Scherrer equation used to determine the crystallite size and noticed that it reduced from 34 to 21 nm on Ni added in WO 3 and also FESEM study give the average grain size of NPs around 30 nm. HRTEM and SAED studies reveals the nanocomposite phase with lattice spacing of ~0.37 nm, and ~0.29 nm, which is perfectly matched with (020) of WO 3 and (111) of NiWO 4 , respectively. FTIR analysis reveals the functional groups of the formation of WO 3 /NiWO 4 NCs. Diffused reflectance spectroscopy was employed to determine the energy gap (E g) through Kubelka-Munk relation and noticed that the E g value is reduced from 2.61 to 2.49 eV. PL emission analysis was done under 280 nm excitation and possess the intense emission peaks at 361, 383, 412, and 492 nm, among them 383 nm is high intense, which is originated from near band edge transition. The photocatalytic degradation of Methylene blue (MB) dye was investigated under UV light. The percent degradation of MB dye was observed to be ~70.83%, 71.88%, 76.39%, 86.81% and 90.63% for pure WO 3 , 5 wt% Ni, 10 wt% Ni, 15 wt% Ni and 20 wt% Ni nanocomposites, respectively. The maximum percent photodegradation of MB dye has been done ∼90.63% for 20 wt% Ni within 80 min of duration. These outcomes revealed that the prepared WO 3 /NiWO 4 NCs will be highly applicable for hazardous MB dye degradation. BET analysis, pseudo-first-order kinetic plot for photo-degradation of MB solution and elemental trapping experiment. [Display omitted] • Facile synthesis of novel WO 3 and WO 3 /NiWO 4 nanocomposites was attained via low-cost co-precipitation method. • XRD, XPS & EDX analyses confirm the synthesis of WO 3 and WO 3 /NiWO 4 nanocomposite. • TEM/HRTEM/SAED analyses confirm low dimension spherical NPs synthesis. • Energy gap systematically reduced from 2.61 to 2.49 eV on increasing the Ni concentrations in WO 3. • Highest photocatalytic degradation of MB dye was noticed for 20% Ni (WO 3 /NiWO 4) specimen. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nanostructured MoS 2 thin films were prepared on glass substrate by JNSP technique. • The elongated irregular rod-like structures were revealed through FESEM. • The MoS 2 films deposited at 450 °C exhibit minimum band gap. • We have fabricated p-Si/n-MoS 2 junction diode for different substrate temperature. • A minimum ideality factor of 2.23 was obtained for 550 °C. Inorganic two-dimensional materials are gradually becoming resources for modern electronic device manufacturing. Fascinate of 2D transition metal dicholgonides (TMDs) are particularly high. TMDS are very great potential for their characteristics and band gap structure in optoelectronic devices. In TMDs, 2D MoS 2 is most researchable material due to its good performance and its adequacy of electronic and optoelectronic application. Here we demonstrate MoS 2 thin film for various temperature such as 400, 450, 500, 550 °C via Jet Nebulizer Spray Pyrolysis (JNSP) technique for PN diode application. XRD pattern revealed that the polycrystalline nature of MoS 2 films with hexagonal crystal structure. The elongated irregular rod-like structures were revealed through FESEM. Elemental confirmation studies of Mo and S were done through EDX. The MoS 2 films deposited at 550 °C exhibit minimum band gap. The average conductivity values were found to be increased from 1.730 × 10−8 to 3.877 × 10−7 S/cm with substrate temperature. A positive photo conducting-nature of p-Si/n-MoS 2 diode have been fabricated. Remarkably, the p-Si/n-MoS 2 diode fabricated at 550 °C revealed minimum n values of 2.23. [ABSTRACT FROM AUTHOR]

• Highly sensitive MIS type Schottky diode where fabricated with various concentration of Ce. • Incorporation of Ce ions effectively reduce the surface roughness value of the V 2 O 5 films. • The fabricated Cu/Ce-V 2 O 5 /n-Si Schottky diodes are showed superior performed in under light condition. • Diode fabricated with 6 wt.% achived achived a very highy photosensitivity of 96090.78 %. In the present work, we have fabricated a highly photo responsive Schottky barrier diode based on cerium infused vanadium pentoxide thin film (Ce-V 2 O 5) as a interfacial layer. It was coated on a glass slide by low-cost sol-gel spin-coating technique and annealed at 500 °C. Structure, surface morphology, optical and electrical characteristic of Ce infused V 2 O 5 films with different Ce concentrations viz 0, 2, 4 and 6 wt% were investigated. X-ray diffraction (XRD) pattern exposed that all coated films are tetragonal structure. And a peak shift was recorded after doping Ce ion into the V 2 O 5 system. FE-SEM images showed a smooth nanorods and nanoplate-like structures in nano-scale region. Topology view by AFM showed a significant decrease in surface roughness of the film at different wt.% of Ce. The incorporation of Ce concentration based on the optical absorbance and band gap energy were studied, using UV–vis spectroscopy. Current-voltage (I–V), characteristics, photo-diode parameters of the Cu/Ce-V 2 O 5 /n-Si diodes were evaluated under dark and light exposed conditions. A maximum quantum efficiency of 25.54 % was achieved for the MIS diode fabricated with 6 % of Ce. The photosensitivity of the Cu/Ce-V 2 O 5 /n-Si diode 100 times higher than pure diode. Photodiode parameters and I–V analysis revealed that Ce with 6 wt.% is appropriate for the development of high quality photodiode and photo detector applications based to its electrical-performance. [ABSTRACT FROM AUTHOR]