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• The elastic recoil detection analysis shows 41 at.% of H absorbed in CP-Ti. • The amount of hydrogen absorbed by Ti-6Al-4V alloy was 31 at.%. • Pd layer improved the hydrogen absorption capacity of Ti-6Al-4V alloy to 36 at.%. • The H depth profile shows the highest diffusion depth in CP-Ti. Hydrogen storage capacity of CP-Ti, Ti-6Al-4V alloy, and Ti-6Al-4V alloy coated with a thin Pd layer was investigated. All samples were hydrogenated at 550 °C for 3 h in 15% hydrogen and 85% argon gas mixture. The hydrogen content and its depth profile were investigated using elastic recoil detection analysis (ERDA) while the X-ray diffraction was used for phase analysis. The highest average content of hydrogen of (41 ± 60) at.% was absorbed in CP-Ti while (31 ± 4) at.% H was determined in Ti-6Al-4V alloy. The presence of a thin Pd catalytic layer improved the hydrogen absorption of alloy to (36 ± 3) at.% H. With the beam energy of 3 MeV, H was profiled up to (4520 ± 410) × 1015 atoms/cm2, (3250 ± 300) × 1015 atoms/cm2 and (3950 ± 360) × 1015 atoms/cm2 in CP-Ti, Ti-6Al-4V alloy and in the coated system respectively. The TiH 2 hydrides were found in all three systems in addition to Pd 3 Ti phase in the Pd/Ti-6Al-4V coated system. [ABSTRACT FROM AUTHOR]

Abstract Silicon (Si) has been the most widely used semiconductor for decades, playing an important role in the field of electronics, energy conversion and energy storage. Because of their unique morphological energy band characteristics, Si nanostructures exhibit superior performance in many applications in comparison with their bulk counterparts. In this study, the effects of thermal annealing on elemental composition and morphological properties of palladium metal thin films grown on c-Si substrates were investigated. Palladium (Pd) thin films of different thicknesses were deposited on Si (1 0 0) with and without native oxide layers by electron beam evaporation and annealed in vacuum at 600 °C for two hours. Scanning electron microscopy (SEM) studies have shown that the surface morphology showed an effective dewetting in individual droplets and islands which further coalesce into bigger islands. Rutherford backscattering spectrometry (RBS) and electrical measurements analyses revealed the diffusion of the Si substrate into the Pd layer during annealing. This contribution will discuss the effects of the metal layer thickness as well as the native oxide on the metal thin films. [ABSTRACT FROM AUTHOR]

Hydrogen effusion from hydrogenated amorphous silicon (a-Si:H) and amorphous silicon carbide (a-Si 1− x C x :H) thin films during a temperature ramp between RT and 600 °C was studied by in situ real-time elastic recoil detection analysis. Point to point contour maps show the hydrogen depth profile and its evolution with the ramped temperature. This paper proposes a diffusion limited evolution model to study H kinetic properties from total retained H contents recorded in a single ramp. In a compact a-Si:H layer where H predominantly effuses at high temperatures between 500 and 600 °C, an activation energy value of ∼1.50 eV and a diffusion pre-factor of 0.41 × 10 −4 cm 2 /s were obtained. Applied to an non-stoichiometric a-Si 1− x C x :H film in the same range of temperature, the model led to reduced values of activation energy and diffusion prefactor of ∼0.33 eV and 0.59 × 10 −11 cm 2 /s, respectively. [ABSTRACT FROM AUTHOR]

Ion beam induced modification of thin metallic films is an emerging approach to grow metallic nanoparticles controllably. Modification of thin solid films is helpful in fabricating arrays of nanoscale particles for electronic and photonic devices and for the catalyzed synthesis of nanotubes and nanowires. In this work, the modification and nanostructures formation over the surface of SiC/Pd thin films of 15 and 45 nm thicknesses, grown on crystalline Silicon (c-Si) substrate by electron beam deposition, upon ion irradiation, have been investigated by means of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Rutherford backscattering spectrometry (RBS), Fourier Transform Infrared Spectroscopy (FTIR) and Raman spectroscopy. The SiC/Pd bilayer films were irradiated with 100 keV Ar+ ions at fluences of 1 × 1015 and 5 × 1015 ions/cm2 at room temperature. The surface morphology from SEM analysis showed the formation of nanoparticles that were interconnected after irradiation. The RBS and EDS results confirmed the presence of Pd, C, O and Si. While the Raman spectrum of the pristine sample displayed only a sharp peak at 520 cm−1 characteristic to c-Si substrate, the spectra of the irradiated sample red-shifted to lower wavenumbers indicating the appearance of Si nanocrystals.. Hence, ion beam irradiation is a promising method for the fabrication of SiC nanostructures on c-Si substrate. [ABSTRACT FROM AUTHOR]