Papers by Keyword: Hydrogen Evolution

Paper TitlePage

Authors: Ryo Niishiro, Akihiko Kudo
Abstract: This review paper represents photocatalytic properties of metal cation-doped TiO2 (rutile) and SrTiO3 photocatalysts for O2 evolution from an aqueous silver nitrate solution and H2 evolution from an aqueous methanol solution under visible light irradiation. Photocatalytic activities for the O2 evolution of Cr/Sb and Rh/Sb-codoped TiO2 are strongly dependent on the codoping ratio and the amount of doped chromium and rhodium. The codopant controls the oxidation number of doped chromium and rhodium. Rh-doped SrTiO3 in which the doped Rh species possesses a reversible redox property is active for the H2 evolution reaction under visible light irradiation. Overall water splitting under visible light irradiation proceeds with Z-scheme photocatalyst systems consisting of the Rh-doped SrTiO3 as a H2 evolution photocatalyst combined with BiVO4 as an O2 evolution photocatalyst and an Fe3+/Fe2+ electron mediator.
Authors: Magdalene Edet Ikpi, Jun Hua Dong, Wei Ke
Abstract: The corrosion behaviour of AM60 magnesium alloy containing 1.88 wt.% Cd in 0.1 M NaCl solution was investigated by weight loss and hydrogen evolution measurements. The microstructure was evaluated using EPMA. Cd was observed to have an even distribution, hence, no new phase was formed. The corrosion resistance was enhanced by the addition of Cd. The rate of corrosion reduced by a factor of 1.5 times that of AM60 alloy. The microstructure played a crucial role as the presence of defects in the alloys initiated and accelerated corrosion.
Authors: Takumi Haruna, Daiki Nishiwaki, Midori Nishikawa
Abstract: Effect of potential on hydrogen evolution during simulated pitting of aluminum has been investigated. Aluminum wire in 1.0 mm diameter was mounted in resin, immersed in 0.6 kmol.m-3 NaCl solution and anodically dissolved in axial direction by applying a constant potential from-0.6 to-0.1 VAg/AgCl for 86.4 ks. In addition, a resistance of the solution in the crevice of the resin where the aluminum wire corroded was simultaneously measured by superimposing high-frequency alternating potential (Ep-p=10 mV) to the main potential. As higher main potential was applied, the corrosion depth increased. Hydrogen evolved at the corroded site although the anodic potentials were applied. The amount of hydrogen evolution increased as higher main potential was applied to the wire. An interfacial potential (Eint) at just the wire surface was calculated from applied main potential (Eapp), solution resistance (Rsol) and current (I) as Eint = Eapp - I.Rsol. The interfacial potential was about-0.7 to-1.0 VAg/AgCl, and became lower as the higher main potential was applied. The lower interfacial potential may cause hydrogen evolution in this case.
Authors: Bin Yang, Neng Huang
Abstract: In order to reduce production cost of making H2, one of the key points was to reduce Pt loading in Pt/C catalytic electrode. In our study, a new type of Pt/C membrane electrodes, PtCuLaOx/C heterogeneous structure, in which with developing different flow of O2, on the surface of carbonaceous substrates were manufactured by Ion Beam Sputtering (IBS) technology. These membrane electrodes were treated by annealing in vacuum furnace, and by different time in different concentration H2SO4 solution. The hydrogen evolution properties of these electrodes were tested by tri-electrode system, and were calculated results of their exchange current density (i0), decomposition voltage (Ed) and active specific surface area (ESA). It was found that PtCuLaOx heterogeneous membrane electrodes with Pt loading less than 0.041mg•cm-2 (the electrode area) undergone treatment, whose Ed, i0 and ESA was -0.223(V vs SCE), 4.562mA•cm-2 and 46.2811m2•g-1 respectively in balanced condition.
Authors: Seok Woo Jin, A. Van Neste, Edward Ghali, D. Guay, Robert Schulz
Authors: Jing Guo Zhang, Shao Ming Zhang, Shuo Li, He Dai, Qiang Hu, Bin Zhang, Li Min Wang
Abstract: Nickel foam-based Ni-Mo alloy electrodes, Ni+Mo composite electrodes and Ni+Mo/Ni-Mo composite alloy electrodes were prepared by eletrodeposition, and the electrocatalytic characteristics for hydrogen evolution reaction (HER) in 30wt% KOH solution were investigated by cathode polarization curve and electrochemical impedance spectroscopy (EIS). The experimental results show that in comparison with nickel foam electrodes, these electrodes exhibit a lower overpotential, a higher exchange current density and a larger real surface area for HER. At 30°C and current density of 200 mA/cm2, the overpotentials of foam Ni electrodes, nickel foam-based Ni-Mo alloy electrodes, Ni+Mo composite electrodes, Ni+Mo/Ni-Mo electrodes are respectively 506, 252, 336, 202 mV. The nickel foam-based Ni+Mo/Ni-Mo composite alloy electrode had the highest HER electrocatalytic activity.
Authors: E. Irissou, M. Blouin, Robert Schulz, L. Roué, D. Guay
Authors: S. Daniele, C. Bragato, M.-A. Baldo, G.A. Battiston, R. Gerbasi
Authors: Ning Li, Jian Meng Huang, Wei Zeng Chen, Bin Wang
Abstract: The amorphous-nanocrystal Ni-Mo deposits were obtained by electrodeposition in alkaline nickel carbonate solution. X-ray diffraction (XRD), scanning electron microscopy (SEM) and modern technologies were used to describe the content, microstructure and morphology of the deposits. The electrochemical characteristics of Ni-Mo deposits were electrolyzed in 33°C, 7 mol/L NaOH electrolytic solutions. The results showed that when I was 100 mA·cm2, the hydrogen evolution potential of Ni-Mo21.76 was lower than amorphous Ni-Mo26.36 and 250mV lower than the nanocrystal Ni cathode. And the Ni-Mo deposits with more amorphous phase content would be in lower hydrogen evolution overpotential, a higher exchange current density, and a better electrolytic stability. These due to the amorphous combined with nanocrystal, lager contact surface and binding energy of Ni-Mo structure.
Showing 1 to 10 of 32 Paper Titles