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The trimanganese tetraoxide (Mn3O4) nanostructured thin films doped with 2 mol% of nickel (Ni) and molybdenum (Mo) ions were deposited by a simple electrophoretic deposition technique. The structural, optical, and morphological studies of these doped thin films were compared with pure Mn3O4 thin films. X-ray diffraction (XRD) confirmed the tetragonal Hausmannite spinel structure. The Fourier transform infrared spectroscopy (FTIR) provided information about the molecular composition of the thin films and the presence of specific chemical bonds. The optical study and band gap energy values of all thin films were evaluated by the UV-visible spectroscopy technique. The scanning electron microscopy (SEM) illustrated the morphological modifications of the Mn3O4 thin films due to doping of the nickel and molybdenum ions. The Brunauer Emmett Teller (BET) method has confirmed the mesoporous nanostructure and nanopores of the thin films. The supercapacitive performance of the thin films was studied by cyclic voltammetry (CV), and galvanostatic charge discharge (GCD) techniques using the threeelectrode arrangement. An aqueous 1M Na2SO4 electrolyte was used for the electrochemical study. The 2 mol% Ni-doped Mn3O4 thin film has shown maximum specific capacitance than pure and Mo-doped Mn3O4 thin films. Hence, this study proved the validity of the strategy - metal ion doping of Mn3O4 thin films to develop it as a potential candidate for electrode material in futuristic energy storage and transportation devices. [ABSTRACT FROM AUTHOR]

We report the effect of nickel (Ni) ion doping on the structure, morphology, and supercapacitive performance of Mn3O4 thin film electrodes, deposited by a simple electrophoretic deposition technique. The structural and compositional studies of these thin films were conducted by x-ray diffraction and Fourier transform infrared spectroscopy. The morphological and optical properties were investigated by scanning electron microscopy, transmission electron microscopy, and UV–visible spectroscopy. These studies confirmed the nanoflake-type surface morphology of nickel-doped thin films. X-ray photoelectron spectroscopy provided information about various valence states and surface composition of the thin films. Cyclic voltammetry study confirmed the surface redox pseudocapacitive behavior of all thin films. The 2 mol.% nickel ion-doped thin film electrode displayed the highest specific capacitance of 816 F g−1 and was evaluated from the galvanostatic charge/discharge curve. It also exhibited outstanding cyclic stability, with 93% capacitance retention after 2000 cycles. Electrochemical impedance spectroscopy revealed the improved supercapacitive performance of the nickel-doped Mn3O4 thin film electrodes, attributed to improved conductivity and charge transport for surface redox reactions. Thus, the present study suggests that the nickel-doped Mn3O4 thin film is a promising candidate as electrode material in supercapacitors. [ABSTRACT FROM AUTHOR]

In present study, using simple and inexpensive novel reflux method, Cadmium Oxide (CdO) thin films were successfully deposited on glass substrate. Here to deposit CdO on glass substrate, Cadmium Chloride (CdCl2) was used as a source of Cd+ ions, while ammonia was taken as complexing agent. Structural analysis and surface morphology of prepared CdO thin film was analyzed by X-ray diffraction and scanning electron microscopy respectively, Also wettability test was done by using goniometer which showed hydrophilic nature of deposited CdO thin film. Optical properties of CdO thin film was completed by using UV-Visible spectroscopy which revealed that deposited CdO thin film has direct band gap about 2.01 eV. NO2 gas sensing properties like sensitivity, response recovery & response time of prepared CdO sensor was determined by using Keithley gas sensing unit. In present work effect of concentration of NO2 gas on response of CdO sensor was studied and it was cleared that as NO2 gas concentration increases (25 ppm – 100 ppm), the response of CdO sensor was also increases & it becomes maximum i.e. (57 %) for 100 ppm of NO2 with optimized temperature of 200°C. Variation of response and recovery time with NO2 gas concentration was studied and it was concluded that as concentration of NO2 gas increases, response time increases while recovery time decreases. [ABSTRACT FROM AUTHOR]

Simple chemical route namely Chemical Bath Deposition (CBD) has been successfully employed for deposition of Bismuth Selenide (Bi2Se3) nanoparticles on porous TiO2 at room temperature. The effect of deposition time of Bi2Se3 on structural, surface morphological and optical properties of TiO2/Bi2Se3 bilayer film has been systematically investigated. X-ray diffraction and energy dispersive X-ray spectra analysis was confirmed the Bi2Se3 nanoparticles are of effectively deposited on anatase TiO2 film. Field Emission Scanning Electron Microscopy (FESEM) images shows the TiO2 film uniformly covers by Bi2Se3 nanoparticles. Optical absorption spectrum is reflecting the considerable enhancement in absorption of visible light with increasing deposition time of Bi2Se3 on TiO2 thin film. [ABSTRACT FROM AUTHOR]

In this work, the nanoflakes of Co(OH)2 have been grown successfully on a stainless steel (SS) substrate at an ambient temperature. The novel architecture, binder free synthesis and considerable capacitance of Co(OH)2 nanoflakes render them as a potential candidate to be used as an electrode material for supercapacitor application. It is observed that the different cathodic potentials have a dramatic impact on the growth mechanism of Co(OH)2 nanoflakes. The prepared thin films were subjected for their structural and morphological study using X-ray diffraction, field emission scanning electron microscope, energy dispersive X-ray spectroscopy, etc. The supercapacitive properties of Co(OH)2 nanoflakes have been studied using cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy techniques. The Co(OH)2 nanoflakes evaluated a maximum specific capacitance of 275 F g−1 for 5 mV s−1 in 1 M KOH. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO) thin films have been synthesized using electrodeposition in potentiostatic mode and the effect of different deposition potentials on their structural, morphological, optical, and electrochromic (EC) properties investigated. The deposition potential versus saturated calomel electrode (SCE) was varied from −0.35 V to −0.50 V in steps of −0.05 V for 20 min each. The electrodeposited WO thin films were characterized using x-ray diffraction analysis, micro-Raman spectroscopy, field-emission scanning electron microscopy, and ultraviolet-visible (UV-Vis) spectrophotometry, revealing amorphous nature with nanograins having average size from 40 nm to 60 nm. The EC performance of the WO thin films exhibited response times of 1.35 s for bleaching ( t ) and 3.1 s for coloration ( t ) with excellent reversibility of 64.36%. The highest coloration efficiency of the electrodeposited WO thin films was found to be 87.95 cm/C. The electrochemical reversibility and stability of the WO thin films obtained in this study make them promising for use in smart window applications. [ABSTRACT FROM AUTHOR]

Nanocrystalline Copper sulphide (Cu2S) thin films have been grown on glass surface by Modified chemical bath deposition method (M-CBD). The optimized preparative parameters including temperature, pH of solution, immersion time, immersion cycles, have been optimized for fine nanocrystalline film growth. As deposited nanocrystalline Copper sulphide (Cu2S) thin films have been made characterized for the structural, surface morphological, optical and electrical properties using X-ray diffraction (XRD), Scanning electron microscopy (SEM), UV-VIS Spectra and d.c. two point probe method. [ABSTRACT FROM AUTHOR]

Suitable host lattice and morphology for easy intercalation and deintercalation process are crucial requirements for electrochromic device. In this investigation, the evolution of structural and morphological changes and their effect on electrochromic (EC) properties of spray-deposited WO3 thin films are studied. Films of different morphologies were deposited from an ammonium tungstate precursor solution using a novel pulsed spray pyrolysis technique (PSPT) on tin-doped indium oxide (ITO) coated glass substrates by varying quantity of spraying solution. Interesting morphological transition from beads-to-wires-to-fibers as a function of quantity of sprayed solution has been demonstrated. The porosity, crystallinity and “open” structures in the films consisting of beads, wires, and fiber-like morphology enabled us to correlate these aspects to their EC performance. WO3 films comprising wire-like morphology (20 cc spraying quantity) exhibited better EC properties both in terms of coloration efficiency (42.7 cm2/C) and electrochemical stability (103 colored/bleached cycles) owing to their adequate open structure, porosity, and amorphicity, compared with the films having bead/fiber-like morphology. [ABSTRACT FROM AUTHOR]

The article discusses the characteristics of chemically deposited nanocrystalline lead sulfide (PbS) thin films. Nanocrystalline materials shows increased strength, hardness, enhance diffusivity, improved quality, roughness, reduced elastic modulus, higher thermal expansion coefficient among others. PbS received attention because of its actual and potential application in optoelectronic devices. It was also investigated for photo thermal conversion application by the solar energy research.

Abstract: Carrier mobilities in thin films of copolymers with repeat units consisting of oligothiophenes bridged by Si atoms are measured over a range of doping levels, where the numbers of thienylenes in the repeat unit are 7, 8, 10, 12, and 14. The mobilities for these polymer films increased with the increase in doping level and the mobility enhancement followed an increasing order of the π-conjugation length. The magnitude of the mobility increase for the Si polymer comprising 14 thiophene units reached ca. 104, implying that this π-conjugation length is almost sufficient to reproduce transport properties of polythiophenes. [Copyright &y& Elsevier]