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P S Patil - One of the best experts on this subject based on the ideXlab platform.

  • efficient electrochromic Nickel Oxide thin films by electrodeposition
    Journal of Alloys and Compounds, 2010
    Co-Authors: A C Sonavane, Akbar I Inamdar, Pravin S Shinde, H P Deshmukh, R S Patil, P S Patil
    Abstract:

    Abstract Nickel Oxide (NiO) thin films were prepared by electrodeposition technique onto the fluorine doped tin Oxide (FTO) coated glass substrates in one step deposition at 20, 30, 40 and 50 min deposition times respectively. The effect of film thickness (thereby microstructural changes) on their structural, morphological, optical and electrochromic properties was investigated. The mass change with potential and cyclic voltammogram was recorded in the range from +0.3 to −0.8 V versus Ag/AgCl. One step deposition of polycrystalline cubic phase NiO was confirmed from X-ray diffraction study. Optical absorption study revealed direct band gap energy of 3.2 eV. The optical transmittance of the film decreased with increase in film thickness. A uniform granular and porous morphology of the films deposited for 20 min was observed. The film becomes more compact and devoid of pores when deposition time was increased to 30 min. Thereafter severe cracks are observed. All the films exhibit anodic electrochromism in OH− containing electrolyte (0.1 M KOH). The maximum coloration efficiency of 107 cm2/C and electrochemical stability of up to 104 colour/bleach cycles were observed for the films deposited for 20 min (film thickness of 104 nm).

  • preparation and characterization of spray pyrolyzed Nickel Oxide nio thin films
    Applied Surface Science, 2002
    Co-Authors: P S Patil, L D Kadam
    Abstract:

    A simple and inexpensive spray pyrolysis technique (SPT) was employed to deposit Nickel Oxide (NiO) thin films from hydrated Nickel chloride salt solution on to glass substrates. The thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques were used to study the thermal characteristics of the precursor salt. The effect of the volume of sprayed solution on structural, optical and electrical properties was studied using X-ray diffraction (XRD), infrared (IR), optical absorption, electrical resistivity and thermoelectric power (TEP) techniques. It is found that increase in the volume of sprayed solution leads to the increment in film thickness and amelioration of crystallinity of the film, consequently the band-gap energy wanes from 3.58 to 3.4 eV. It also affects resistivity and TEP of the film.

  • studies on electrochromic properties of Nickel Oxide thin films prepared by spray pyrolysis technique
    Solar Energy Materials and Solar Cells, 2001
    Co-Authors: L D Kadam, P S Patil
    Abstract:

    Abstract Electrochromic Nickel Oxide thin films were prepared by using a simple and inexpensive spray pyrolysis technique (SPT) onto fluorine-doped tin Oxide (FTO) coated glass substrates from Nickel chloride solution. Transparent NiO-thin films were obtained at a substrate temperature 350°C. The films were cubic NiO with preferred orientation in the (1 1 1) direction. Infrared spectroscopy results show presence of free hydroxyl ion and water in Nickel Oxide thin films. The electrochromic properties of the thin films were studied in an aqueous alkaline electrolyte (0.1 M KOH) using cyclic voltammetry (CV), chronoamperometry (CA) and spectrophotometry. The films exhibit anodic electrochromism, changing colour from transparent to black. The colouration efficiency at 630 nm was calculated to be 37 cm 2 /C.

L D Kadam - One of the best experts on this subject based on the ideXlab platform.

  • preparation and characterization of spray pyrolyzed Nickel Oxide nio thin films
    Applied Surface Science, 2002
    Co-Authors: P S Patil, L D Kadam
    Abstract:

    A simple and inexpensive spray pyrolysis technique (SPT) was employed to deposit Nickel Oxide (NiO) thin films from hydrated Nickel chloride salt solution on to glass substrates. The thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques were used to study the thermal characteristics of the precursor salt. The effect of the volume of sprayed solution on structural, optical and electrical properties was studied using X-ray diffraction (XRD), infrared (IR), optical absorption, electrical resistivity and thermoelectric power (TEP) techniques. It is found that increase in the volume of sprayed solution leads to the increment in film thickness and amelioration of crystallinity of the film, consequently the band-gap energy wanes from 3.58 to 3.4 eV. It also affects resistivity and TEP of the film.

  • studies on electrochromic properties of Nickel Oxide thin films prepared by spray pyrolysis technique
    Solar Energy Materials and Solar Cells, 2001
    Co-Authors: L D Kadam, P S Patil
    Abstract:

    Abstract Electrochromic Nickel Oxide thin films were prepared by using a simple and inexpensive spray pyrolysis technique (SPT) onto fluorine-doped tin Oxide (FTO) coated glass substrates from Nickel chloride solution. Transparent NiO-thin films were obtained at a substrate temperature 350°C. The films were cubic NiO with preferred orientation in the (1 1 1) direction. Infrared spectroscopy results show presence of free hydroxyl ion and water in Nickel Oxide thin films. The electrochromic properties of the thin films were studied in an aqueous alkaline electrolyte (0.1 M KOH) using cyclic voltammetry (CV), chronoamperometry (CA) and spectrophotometry. The films exhibit anodic electrochromism, changing colour from transparent to black. The colouration efficiency at 630 nm was calculated to be 37 cm 2 /C.

Claesgoran Granqvist - One of the best experts on this subject based on the ideXlab platform.

Rudi Cloots - One of the best experts on this subject based on the ideXlab platform.

  • Surfactant-assisted ultrasonic spray pyrolysis of Nickel Oxide and lithium-doped Nickel Oxide thin films, toward electrochromic applications
    Applied Surface Science, 2014
    Co-Authors: Jessica Denayer, Geoffroy Bister, Anthony Maho, Bénédicte Vertruyen, Véronique Lardot, P. Simonis, Philippe Aubry, Pierre Colson, Catherine Henrist, Francis Cambier, Rudi Cloots
    Abstract:

    Lithium-doped Nickel Oxide and undoped Nickel Oxide thin films have been deposited on FTO/glass substrates by a surfactant-assisted ultrasonic spray pyrolysis. The addition of polyethylene glycol in the sprayed solution has led to improved uniformity and reduced light scattering compared to films made without surfactant. Furthermore, the presence of lithium ions in NiO films has resulted in improved electrochromic performances (coloration contrast and efficiency), but with a slight decrease of the electrochromic switching kinetics.

Michael Gratzel - One of the best experts on this subject based on the ideXlab platform.

  • an optically transparent iron Nickel Oxide catalyst for solar water splitting
    Journal of the American Chemical Society, 2015
    Co-Authors: Carlos G Moralesguio, Matthew T Mayer, Aswani Yella, David S Tilley, Michael Gratzel
    Abstract:

    Sunlight-driven water splitting to produce hydrogen fuel is an attractive method for renewable energy conversion. Tandem photoelectrochemical water splitting devices utilize two photoabsorbers to harvest the sunlight and drive the water splitting reaction. The absorption of sunlight by electrocatalysts is a severe problem for tandem water splitting devices where light needs to be transmitted through the larger bandgap component to illuminate the smaller bandgap component. Herein, we describe a novel method for the deposition of an optically transparent amorphous iron Nickel Oxide oxygen evolution electrocatalyst. The catalyst was deposited on both thin film and high-aspect ratio nanostructured hematite photoanodes. The low catalyst loading combined with its high activity at low overpotential results in significant improvement on the onset potential for photoelectrochemical water oxidation. This transparent catalyst further enables the preparation of a stable hematite/perovskite solar cell tandem device, which performs unassisted water splitting.