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Present work reports the growth of BFO/WO3 bilayer thin film structures over Silicon, corning and ITO coated glass substrates. BFO layer in BFO/WO3 bilayer structure was deposited using Pulsed Laser deposition (PLD) technique at optimized laser energy (200 mJ) while WO3 nanostructured layer was deposited using rf‐magnetron sputtering technique at varying glancing angle from 65° to 80°. For the realization of MBM (metal‐bilayer‐metal) device, top Gold (Au) electrodes have been deposited using thermal evaporation technique. The BFO/WO3 bilayer structure fabricated at 70° glancing angle exhibited the saturation (Ps) and remnant (Pr) polarization as 45.45 μC/cm2 and 21.52 μC/cm2 respectively, which are appreciably higher than the earlier reports for pure BFO thin films. Enhanced energy storage characteristics were obtained in Au/BFO/WO3/ITO structure fabricated at 70° glancing angle with charge‐discharge efficiency (63%) and enlarged recoverable energy density (467 mJ/cm3). Achieved results indicate the utilization of fabricated Au/BFO/WO3/ITO structures towards high energy storage applications. [ABSTRACT FROM AUTHOR]

Transparent polycrystalline TiO2 thin films have been deposited on unheated glass substrates using RF reactive magnetron sputtering. Depositions were carried out at different glancing angles and with different total gas mixture pressures. The variation of these parameters affected the crystal phase composition and the surface morphology. Depending on the glancing angle and the pressure, rutile, mixed anatase/ rutile and pure anatase were deposited at low substrate temperature. Both hydrophilic and hydrophobic TiO2 were obtained, exhibiting fast photoconversion to superhydrophilic upon UV irradiation. The effect of the materials physicochemical properties on the wettability and rate of the UV induced superhydrophilicity is evaluated. [ABSTRACT FROM AUTHOR]

Tungsten oxide thin films are prepared by glancing‐angle reactive magnetron sputtering at room temperature. The surface and cross‐section morphologies are characterized by FE‐SEM and TEM. The electrochromic properties of the thin films are studied using a three‐electrode system in 1 m LiClO4/PC solution. When the glancing angle is kept at 80°, a nanocolumnar structured film is obtained. This nanocolumnar structured film shows a lower driving potential and better stability compared to the dense film. The charge capacity per unit area of the nanocolumnar structured film is determined to be 30.85 mc cm−2. The diffusion rates of injection and detachment of ions are determined to be Din = 6.57 × 10−10 cm2 s−1 and Dde = 6.55 × 10−10 cm2 s−1 under an applied potential of ±1.2 V, respectively. The optical modulation amplitude of the nanocolumnar structured film reaches 65% at a wavelength of 600 nm and the optical density is superior to that of the dense film. [ABSTRACT FROM AUTHOR]

Crystalline TiO2 films were prepared on unheated glass substrates by radio frequency (RF) reactive magnetron sputtering at normal angle of incidence (a = 0°) and at glancing angle (a = 87°). The effect of the glancing angle on the structure, microstructure, and wetting properties of the films was investigated. The inclination of the substrate led to phase transformation of the deposited films from rutile to either rutile/anatase or anatase, depending on the working pressure. Extreme shadowing at 87° results in a remarkable increase of the films' porosity and surface roughness. The mechanism of the glancing-angle-induced crystalline phase formation is thoroughly discussed based on the thermodynamic, kinetic, and geometrical aspects of the nucleation and is related with the microstructural changes. Both crystalline phase and microstructure significantly affect the wetting properties of the TiO2 films. Glancing-angle-deposited anatase TiO2 exhibits a high degree of porosity and roughness, a high rate of UV-induced wettability conversion, and a long-term highly hydrophilic nature in dark. Therefore, anatase TiO2 is potentially a good candidate for applications as dye-sensitized solar cells (DSSC)/perovskite solar cells, microfluidic devices, and self-cleaning surfaces prepared on thermosensitive substrates. [ABSTRACT FROM AUTHOR]