Advertisement

Primary Oxide Latent Storage and Spillover for Reversible Electrocatalysis in Oxygen and Hydrogen Electrode Reactions

  • Milan M. Jaksic
  • Angeliki Siokou
  • Georgios D. Papakonstantinou
  • Jelena M. JaksicEmail author
Chapter
Part of the Nanostructure Science and Technology book series (NST)

Abstract

Ever since Sir William Grove invented gas fed fuel cells (FC), the main electrocatalytic challenge has been to establish the reversible oxygen electrode (ROE) to take advantage of the entire thermodynamically available current/voltage range between hydrogen and oxygen evolving limits. This challenge is the main subject of the present study.

Now, hypo-d-(f)-oxides of transition elements (d ≤ 5) have the pronounced effect of causing spontaneous adsorptive dissociation of water molecules, which is the main and initial thermodynamic precondition for the reversible latent storage and spillover properties of primary oxides (Pt-OH, Au-OH), indispensable ingredients in electrocatalysis for the oxygen electrode reactions. The higher the altervalent number (or capacity) of these oxides, given the proper valence in the hypo-d-(f)-oxide supports, the higher the overall (electro)catalytic yields for cathodic oxygen reduction (ORR) and anodic evolution (OER). In fact, cyclic voltammetry reveals the interrelated redox properties of the primary (Pt-OH) and surface (Pt=O) oxides in between the cathodic hydrogen and anodic oxygen evolving limits. Of course, the existence of the primary oxides has long been known as the intermediate state between hydrogen oxidation in heterogeneous Doeberriner reaction on Pt catalyst, and self-catalyzation by water molecules (Ertel). Such interfering interrelated and auto-catalytic species substantially define and restrict electrocatalytic properties of plain (Pt, Au), or non-interactive supported noble metals (Pt/C, Au/C), along the potential axis, and within some positive range even make them highly polarizable. Meanwhile, the latter can be continuously electrocatalytically depolarized and reactivated. For more than a century, such spontaneously renewable activation and maintenance of the reversible electrocatalytic state for the oxygen electrode reactions all along cyclic voltammograms has been the main electrocatalytic challenge. So, continuously and spontaneously renewable dissociative adsorption of water molecules upon hypo-d-(f)-oxide supports enables the latent storage and electrocatalytic spillover properties of the primary oxide(s) for the reversible oxygen electrode (ROE) behavior, and Pt-OH and Au-O have been identified and substantiated all along the potential axis between the hydrogen and oxygen evolving limits. Meanwhile, on plain individual transition metals, under such conditions there usually occurs a surface oxide (Pt=O) reaction polarization within a broader positive potential range because of the absence of primary oxide spillover. Such advanced latent storage and spillover of the primary oxide electrocatalytic properties suggests interactive (SMSI—Strong Metal-Support Interaction) nanostructured hyper-d-Pt (Au, RuPt) clusters, which become selectively grafted on individual or composite mixed valence hypo-d-(f)-oxide supports. The latter then feature the extra high stability, pronounced electronic conductivity and many other d-electronic based metal properties mostly arising from the hypo-hyper-d-d-(f)-interelectronic bonding effect, along with spontaneous dissociative water molecules adsorption upon exposed oxide support surfaces, thereby yielding renewable primary oxide latent storage by simple continuous water vapor supply, and characteristic membrane-type hydroxide ions surface migration. Migrating hydroxide, as an individual species, under imposed polarization partially transfers its prevailing electron to the metallic electrocatalyst, thence resulting in a Pt-OH (Au-OH) dipole, and by the surface repulsion obeys reversible spillover distribution and imposes electrocatalytic ROE properties all over the catalyst surface and DL pseudo-capacitance charging and discharging, as well. The strong adsorptive surface oxide (Pt=O → 1) deposition out of the primary oxide (Pt-OH → 0) irreversible disproportionation, thereby imposes unusually high reaction polarization of Pt, Au, Pd and all other noble and transition d-metals within a very broad (600 mV, and even broader) potential range, and thereby, in general, mostly pronounced polarizable non-catalytic properties for oxygen electrode (ORR, OER) reactions. Thus, the strong interactive and selective hypo-hyper-d-d-interelectronic grafting bonded of nanostructured individual (Pt), or prevailing hyper-d-intermetallic phase (MoPt3; HfPd3) cluster catalysts on altervalent and mixed-valence hypo-d-(f)-oxide supports, make possibly primary oxide latent storage and enhanced spillover, and thus enable approaching their reversible (electro)catalytic properties and optimization for the ROE. The reversible alterpolar bronze behaves (Pt/HxNbO5 ⇔ Pt/Nb(OH)5, x ≈ 0.3), as the thermodynamic equilibrium alterpolar state, thereby substantially advanced electrocatalytic properties of these composite interactive electrocatalysts for both oxygen (ORR, OER) and hydrogen (HOR, HER) electrode reactions, and consequently, have been inferred as spontaneously altering, and strong spillover features, in particular unique and superior for the revertible ((PEMFC versus WE) = Water Electrolysis) cells.

Keywords

Oxygen Reduction Reaction Electrocatalytic Activity Hydrogen Evolution Reaction Oxygen Evolution Reaction Mixed Valence 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

The present chapter has been conceived and carried out at the Institute of Chemical Engineering Sciences, ICEHT/FORTH, Patras, Greece.

References

  1. 1.
    Grove WR (1842) On a gaseous voltaic battery. Philos Mag 21:417–420Google Scholar
  2. 2.
    Conway BE (1995) Electrochemical oxide film formation at noble metals as a surface-chemical process. Prog Surf Sci 49:331–452CrossRefGoogle Scholar
  3. 3.
    Angerstein-Kozlowska H, Conway BE, Sharp WBA (1973) The real condition of electrochemically oxidized platinum surfaces: Part I. Resolution of component processes. J Electroanal Chem 43:9–36CrossRefGoogle Scholar
  4. 4.
    Angerstein-Kozlovska H, Conway BE, Hamelin A, Stoicoviciu L (1986/1987) Elementary steps of electrochemical oxidation of single-crystal planes of Au. I. Chemical basis of processes involving geometry of anions and the electrode surfaces, Electrochim Acta 31:1051–1061; II. A chemical and structural basis of oxidation of the (111) plane, J Electroanal Chem 228:429–453Google Scholar
  5. 5.
    Jaksic JM, Krstajic NV, Vracar LJM, Neophytides SG, Labou D, Falaras P, Jaksic MM (2007) Spillover of primary oxides as a dynamic catalytic effect of interactive hypo-d-oxide supports. Electrochim Acta 53:349–361CrossRefGoogle Scholar
  6. 6.
    Krstajic NV, Vracar LJM, Radmilovic VR, Neophytides SG, Labou D, Jaksic JM, Tunold R, Falaras P, Jaksic MM (2007) Advances in interactive supported electrocatalysts for hydrogen and oxygen electrode reactions. Surf Sci 601:1949–1966CrossRefGoogle Scholar
  7. 7.
    Jaksic MM, Botton GA, Papakonstantinou GG, Nan F, Jaksic JM (2014) Primary oxide latent storage and spillover enabling electrocatalysts with reversible oxygen electrode properties and the alterpolar revertible (PEMFC versus WE) cell. J Phys Chem C 118:8723–8746CrossRefGoogle Scholar
  8. 8.
    Papakonstantinou GD, Jaksic JM, Labou D, Siokou A, Jaksic MM (2011) Spillover phenomena and their striking impacts in electrocatalysis for hydrogen and oxygen electrode reactions. Adv Phys Chem 2011:1–22, Article ID 412165CrossRefGoogle Scholar
  9. 9.
    Neophytides SG, Zafeiratos S, Jaksic MM (2003) Selective interactive grafting of composite bifunctional electrocatalysts for simultaneous anodic hydrogen and CO oxidation, I. Theoretical concepts and embodiment of novel type composite catalysts. J Electrochem Soc 150:E512–E526CrossRefGoogle Scholar
  10. 10.
    Neophytides SG, Murase K, Zafeiratos S, Papakonstantinou GD, Paloukis FS, Krstajic NV, Jaksic MM (2006) Composite hypo-hyper-d-intermetallic phases as supported interactive electrocatalysts. J Phys Chem B 110:3030–3042CrossRefGoogle Scholar
  11. 11.
    Jaksic JM, Labou D, Papakonstantinou GD, Siokou A, Jaksic MM (2010) Novel spillover interrelating reversible electrocatalysts for oxygen and hydrogen electrode reactions. J Phys Chem C 114:18298–18312CrossRefGoogle Scholar
  12. 12.
    Ma Y, Balabuena PB (2007) Designing oxygen reduction catalysts: insights from metalloenzymes. Chem Phys Lett 440:130–133CrossRefGoogle Scholar
  13. 13.
    Brewer L (1968) Bonding and structures of transition metals. Science 161:115–122CrossRefGoogle Scholar
  14. 14.
    Jaksic MM (2000) Hypo-hyper-d-electronic interactive nature of synergism in catalysis and electrocatalysis for hydrogen reactions. Electrochim Acta 45:4085–4099CrossRefGoogle Scholar
  15. 15.
    Tauster SJ, Fung SC (1978) Strong metal-support interactions: occurrence among the binary oxides of groups IIA–VB. J Catal 55:29–35CrossRefGoogle Scholar
  16. 16.
    Tauster SJ, Fung SC, Baker RTK, Horsley JA (1981) Strong-interactions in supported metal catalysts. Science 211:1121–1125CrossRefGoogle Scholar
  17. 17.
    Stevenson SA (1987) Metal-support interaction in catalysis, sintering and redispersion. Van Nostrand, New YorkGoogle Scholar
  18. 18.
    Haller GL, Resasco DE (1989) Metal–support interaction: Group VIII metals and reducible oxides. In: Eley DD, Pires H, Weisz PB (eds) Advances in catalysis, vol 36. Academic, San Diego, pp 173–235Google Scholar
  19. 19.
    Neophytides SG, Zafeiratos S, Papkonstantinou GD, Jaksic JM, Paloukis FE, Jaksic MM (2005) Extended Brewer hypo-hyper-d-interionic bonding theory, I. Theoretical considerations and examples for its experimental confirmation. Int J Hydrogen Energy 30:131–147CrossRefGoogle Scholar
  20. 20.
    Neophytides SG, Zafeiratos S, Papakonstantinou GD, Jaksic JM, Paloukis FE, Jaksic MM (2005) Extended Brewer hypo-hyper-d-interionic bonding theory, II. Strong metal-support interaction grafting of composite electrocatalysts. Int J Hydrogen Energy 30:393–410CrossRefGoogle Scholar
  21. 21.
    Vittadini A, Selloni A, Rotzinger FP, Gratzel M (1998) Structure and energetics of water adsorbed at TiO2 anatase (101) and (001) surfaces. Phys Rev Lett 81:2954–2957CrossRefGoogle Scholar
  22. 22.
    Lazzeri M, Vittadini A, Selloni A (2001) Structure and energetics of stoichiometric TiO2 anatase surfaces. Phys Rev B 63. Article No. 155409Google Scholar
  23. 23.
    Livage J, Henry M, Sanchez C (1988) Sol-gel chemistry of transition metal oxides. Prog Solid State Chem 18:259–341CrossRefGoogle Scholar
  24. 24.
    Judeinstein P, Livage J (1991) Sol-gel synthesis of WO3 thin films. J Mater Chem 1:621–627CrossRefGoogle Scholar
  25. 25.
    Livage J, Guzman G (1996) Aqueous precursors for electrochromic tungsten oxide hydrates. Solid State Ion 84:205–211CrossRefGoogle Scholar
  26. 26.
    Koper MTM, Van Santen RA (1999) Interaction of H, O and OH with metal surfaces. J Electroanal Chem 472:126–136CrossRefGoogle Scholar
  27. 27.
    Kohn HW, Boudart M (1964) Reaction of hydrogen with oxygen adsorbed on a platinum catalyst. Science 145:149–150CrossRefGoogle Scholar
  28. 28.
    Benson JE, Kohn HW, Boudart M (1966) On the reduction of tungsten trioxide accelerated by platinum and water. J Catal 5:307–313CrossRefGoogle Scholar
  29. 29.
    Boudart M, Vannice MA, Benson JE (1999) Adlineation, portholes and spillover. Z Phys Chem NF 64:171–177Google Scholar
  30. 30.
    Volkening S, Bedurftig K, Jacobi K, Wintterlin J, Ertl G (1999) Dual path mechanism for catalytic oxidation of hydrogen on platinum surface. Phys Rev Lett 83:2672–2675CrossRefGoogle Scholar
  31. 31.
    Mavrikakis M, Stoltze P, Norskov JK (2000) Making gold less noble. Catal Lett 64:101–106CrossRefGoogle Scholar
  32. 32.
    Awaludin Z, Moo JGS, Okajima T, Ohsaka T (2013) TaOx-capped Pt nanoparticles as active and durable electrocatalysts for oxygen reduction. J Mater Chem A 1:14754–14765CrossRefGoogle Scholar
  33. 33.
    Awaludin Z, Suzuki M, Masud J, Okajima T, Ohsaka T (2011) Enhanced electrocatalysis of oxygen reduction on Pt/TaOx/GC. J Phys Chem C 115:25557–25567CrossRefGoogle Scholar
  34. 34.
    Masuda T, Fukumitsu H, Fugane K, Togasaki H, Matsumura D, Tamura K, Nishihata Y, Yoshikawa H, Kobayashi K, Mori T, Uosaki K (2012) Role of cerium oxide in the enhancement of activity for the oxygen reduction reaction at Pt-CeOx nanocomposite electrocatalyst—an in situ electrochemical X-ray absorption fine structure study. J Phys Chem C 116:10098–10102CrossRefGoogle Scholar
  35. 35.
    Fugane K, Mori T, Ou DR, Yan P, Ye F, Yoshikawa H, Drennan J (2012) Improvement of cathode performance on Pt-CeOx by optimization of electrochemical pretreatment conditions for PEMFC application. Langmuir 8:16692–16700CrossRefGoogle Scholar
  36. 36.
    Ou DR, Mori T, Fugane K, Togasaki H, Ye F, Drennan J (2011) Stability of Ceria Supports in Pt−CeOx/C catalysts. J Phys Chem C 115:19239–19245CrossRefGoogle Scholar
  37. 37.
    Masud J, Alam MT, Okajima T, Ohsaka T (2011) Catalytic electrooxidation of formaldehyde at Ta2O5-modified Pt electrodes. Chem Lett Jpn 40:252–254CrossRefGoogle Scholar
  38. 38.
    Masud J, Alam MT, Miah MR, Okajima T, Ohsaka T (2011) Enhanced electrooxidation of formic acid at Ta2O5-modified Pt electrode. Electrochem Commun 13:86–89CrossRefGoogle Scholar
  39. 39.
    Hammer B, Norskov JK (1995) Why gold is the noblest of all the metals. Nature 376:238–240CrossRefGoogle Scholar
  40. 40.
    Quaino P, Luque NB, Nazmutdinov R, Santos E, Schmickler W (2012) Why is gold such a good catalyst for oxygen reduction in alkaline media? Angew Chem Int Ed 51:1–5CrossRefGoogle Scholar
  41. 41.
    Haruta M (2003) When gold is not noble: catalysis by nanoparticles. Chem Rec 3:75–87CrossRefGoogle Scholar
  42. 42.
    Lina C, Song Y, Cao L, Chen S (2013) Oxygen reduction catalyzed by Au-TiO2 nanocomposites in alkaline media. ACS Appl Mater Interfaces 5:13305–13311CrossRefGoogle Scholar
  43. 43.
    Jaksic MM (1986) Advances in electrocatalysis for hydrogen evolution in the light of the Brewer-Engel valence-bond theory. J Mol Catal 38:161–202CrossRefGoogle Scholar
  44. 44.
    Friedel J, Sayers CM (1977) On the role of d-d-electron correlations in the cohesion and ferromagnetism of transition metals, J. Physique 38:697–705CrossRefGoogle Scholar
  45. 45.
    Gschneidner KA (1964) Physical properties and interrelations of metallic and semimetallic elements. In: Seitz F, Turnbull D (eds) Solid state physics, advances in research and applications, vol 16. Academic, New York, pp 275–427Google Scholar
  46. 46.
    Jaksic MM (2000) Volcano plots along the periodic table, their causes and consequences on electrocatalysis for hydrogen electrode reactions. J New Mater Electrochem Syst 3:153–168Google Scholar
  47. 47.
    Jaksic MM, Lacnjevac CM, Grgur BN, Krstajic NV (2000) Volcano plots along intermetallic hypo-hyper-d-electronic phase diagrams and electrocatalysis for hydrogen electrode reactions. J New Mater Electrochem Syst 3:169–182Google Scholar
  48. 48.
    Jaksic JM, Radmilovic VR, Krstajic NV, Lacnjevac CM, Jaksic MM (2011) Volcanic periodicity plots along transition series, Hypo-hyper-d-d-interelectronic correlations and electrocatalysis for hydrogen electrode reactions. Macedonian J Chem Chem Eng 30:3–18Google Scholar
  49. 49.
    Methfessel M, Hennig D, Schefler M (1992) Trends of the surface relaxations, surface energies, and work functions of the 4d transition metals. Phys Rev B 46:4816–4829CrossRefGoogle Scholar
  50. 50.
    Kita H (1966) Periodic variation of exchange current density of hydrogen electrode reaction with atomic number and reaction mechanism. J Electrochem Soc 113:1095–1111CrossRefGoogle Scholar
  51. 51.
    Miles MH (1975) Evaluation of electrocatalysts for water electrolysis in alkaline solutions. J Electroanal Chem 60:89–96CrossRefGoogle Scholar
  52. 52.
    Trasatti S (1977) The work function in electrochemistry. In: Tobias CW, Goerischer H (eds) Advances in electrochemistry and electrochemical engineering, vol 10. Interscience, New York, pp 213–321Google Scholar
  53. 53.
    Jaksic JM, Vracar LJM, Neophytides SG, Zafeiratos S, Papakonstantinou GD, Krstajic NV, Jaksic MM (2005) Structural effects on kinetic properties for hydrogen electrode reactions and CO tolerance along Mo-Pt phase diagram. Surf Sci 598:156–173CrossRefGoogle Scholar
  54. 54.
    Santos E, Schmickler W (2007) Electrocatalysis of hydrogen oxidation—theoretical foundations. Angew Chem Int Ed 46:8262–8265CrossRefGoogle Scholar
  55. 55.
    Hammer B, Norskov JK (2000) Theoretical surface science and catalysis—calculations and concepts. Adv Catal 45:71–129Google Scholar
  56. 56.
    Christoffersen E, Liu P, Ruban A, Skriver HL, Norskov JK (2001) Anode materials for low-temperature fuel cells: a density functional theory study. J Catal 199:123–131CrossRefGoogle Scholar
  57. 57.
    Peuckert M, Coenen FP, Bonzel HP (1984) XPS study of the electrochemical surface oxidation of platinum in 1N H2SO4 acid electrolyte. Electrochim Acta 29:1305–1314CrossRefGoogle Scholar
  58. 58.
    Drawdy JE, Hoflund GB, Gardner SD, Yngvadottir E, Schryer DR (1990) Effect of pretreatment on a platinized tin oxide catalyst used for low-temperature CO oxidation. Surf Interface Anal 16:369–374CrossRefGoogle Scholar
  59. 59.
    Akita T, Tanaka K, Tsubota S, Haruta M (2000) Analytical high-resolution TEM study of supported gold catalysts: orientation relationship between Au particles and TiO2 supports. J Electron Microsc 49:657–662CrossRefGoogle Scholar
  60. 60.
    Akita T, Lu P, Ichikawa S, Tanaka K, Haruta M (2001) Analytical TEM study on the dispersion of Au nanoparticles in Au/TiO2 catalyst prepared under various temperatures. Surf Interface Anal 31:73–78CrossRefGoogle Scholar
  61. 61.
    Haruta M (1997) Size- and support-dependency in the catalysis of gold. Catal Today 36:153–166CrossRefGoogle Scholar
  62. 62.
    Date M, Haruta M (2001) Moisture effect on CO oxidation over Au/TiO2 catalyst. J Catal 201:221–224CrossRefGoogle Scholar
  63. 63.
    Boccuzzi F, Chiorino A, Tsubota S, Haruta M (1996) FTIR study of carbon monoxide oxidation and scrambling at room temperature over gold supported on ZnO and TiO2. J Phys Chem 100:3625–3631CrossRefGoogle Scholar
  64. 64.
    Boccuzzi F, Chiorino A, Manzoli M, Lu P, Akita T, Ichikawa S, Haruta M (2001) Au/TiO2 nanosized samples: a catalytic, TEM, and FTIR study of the effect of calcination temperature on the CO oxidation. J Catal 202:256–267CrossRefGoogle Scholar
  65. 65.
    Zafeiratos S, Papakonstantinou G, Jaksic MM, Neophytides SG (2005) The effect of Mo oxides and TiO2 support on the chemisorption features of linearly adsorbed CO on Pt crystallites: an infrared and photoelectron spectroscopy study. J Catal 232:127–136CrossRefGoogle Scholar
  66. 66.
    Riess I, Vayenas CG (2003) Fermi level and potential distribution in solid electrolyte cells with and without ion spillover. Solid State Ion 159:313–329CrossRefGoogle Scholar
  67. 67.
    Vayenas CG, Bebelis S, Pliangos C, Brosda S, Tsiplakides D (2001) Electrochemical activation of catalysis: promotion, electrochemical promotion, and metal-support interactions. Kluwer, New YorkGoogle Scholar
  68. 68.
    Vayenas CG, Jaksic MM, Bebelis SI, Neophytides SG (1996) The electrochemical activation of catalytic reactions. In Bockris JO’M, Conway BE, White RE (eds), Modern aspects of electrochemistry, vol 29. Plenum Press, New York, pp 57–202Google Scholar
  69. 69.
    Vayenas CG, Bebelis S, Ladas L (1990) The dependence of catalytic activity on catalyst work function. Nature 343:625–627CrossRefGoogle Scholar
  70. 70.
    Tsiplakides D, Nicole J, Vayenas CG, Comninellis C (1998) Work function and catalytic activity measurements of an IrO2 film deposited on YSZ subjected to in situ electrochemical promotion. J Electrochem Soc 145:905–908CrossRefGoogle Scholar
  71. 71.
    Neophytides S, Tsiplakides D, Stonehart P, Jaksic MM, Vayenas C (1994) Electrochemical enhancement of a catalytic reaction in aqueous solution. Nature 370:45–47CrossRefGoogle Scholar
  72. 72.
    Neophytides SG, Tsiplakides D, Stonehart P, Jaksic MM, Vayenas CG (1996) Non-faradaic electrochemical modification of the catalytic activity of Pt for H2 oxidation in aqueous alkaline media. J Phys Chem 100:14803–14814CrossRefGoogle Scholar
  73. 73.
    Tsiplakides D, Neophytides SG, Enea O, Jaksic MM, Vayenas CG (1997) Non-faradaic electrochemical modification of the catalytic activity of Pt-black electrodes deposited on Nafion 117 solid polymer electrolyte. J Electrochem Soc 144:2072–2078CrossRefGoogle Scholar
  74. 74.
    Tsiplakides D, Vayenas CG (2001) Electrode work function and absolute potential scale in solid-state electrochemistry. J Electrochem Soc 148:E189–E202CrossRefGoogle Scholar
  75. 75.
    Tsiplakides D, Archonta D, Vayenas CG (2007) Absolute potential measurements in solid and aqueous electrochemistry using two Kelvin probes and their implications for the electrochemical promotion of catalysts. Top Catal 44:469–479CrossRefGoogle Scholar
  76. 76.
    Trasatti S (1982) The concept of absolute electrode potential. An attempt at a calculation. J Electroanal Chem 139:1–13CrossRefGoogle Scholar
  77. 77.
    Nicole J, Tsiplakides D, Pliangos C, Verykios XE, Comninellis C, Vayenas CG (2001) Electrochemical promotion and metal-support interactions. J Catal 204:23–34CrossRefGoogle Scholar
  78. 78.
    Metcalfe IS (2001) Electrochemical promotion of catalysts, I. Thermodynamic considerations. J Catal 199:247–258CrossRefGoogle Scholar
  79. 79.
    Metcalfe IS (2001) Electrochemical promotion of catalysts, II. The role of a stable spillover species and prediction of reaction rate modification. J Catal 199:259–272CrossRefGoogle Scholar
  80. 80.
    Markovic NM, Ross PN (2002) Surface science studies of model fuel cell electrocatalysts. Surf Sci Rep 45:117–229CrossRefGoogle Scholar
  81. 81.
    Siokou A, Ntais S (2003) Towards the preparation of realistic model Ziegler-Natta catalysts: XPS study of the MgCl2/TiCl4 interaction with flat SiO2/Si(1 0 0). Surf Sci 540:379–388CrossRefGoogle Scholar
  82. 82.
    Suh M, Bagus PS, Pak S, Rosynek MP, Lunsford JH (2000) Reactions of hydroxyl radicals on titania, silica, alumina, and gold surfaces. J Phys Chem B 104:2736–2742CrossRefGoogle Scholar
  83. 83.
    Lang ND (1989) Theory of single-atom imaging in the scanning tunneling microscope. Comments Condens Matter Phys 14:253–257Google Scholar
  84. 84.
    Jaksic JM, Papakonstantinou GD, Labou D, Siokou A, Jaksic MM (2013) Spillover phenomena in electrocatalysis for oxygen and hydrogen electrode reactions. In: Suib SL (ed) New and future developments in catalysis: hybrid materials, composites, and organocatalysts. Elsevier, Amsterdam, pp 175–212CrossRefGoogle Scholar
  85. 85.
    Engelhard M, Baer D (2000) Third row transition metals by X-ray photoelectron spectroscopy. Surf Sci Spectra 7(1):1–68CrossRefGoogle Scholar
  86. 86.
    Fuentes RE, Garcia BL, Weidner JW (2008) A Nb-doped TiO2 electrocatalyst for use in direct methanol fuel cells. ECS Trans 12:239–248CrossRefGoogle Scholar
  87. 87.
    Bokhimi MA, Novaro O, Lopez T, Sanchez E, Gomes R (1995) Effect of hydrolysis catalyst on the Ti deficiency and crystallite size of sol-gel-TiO2 crystalline phases. J Mater Res 10:2788–2796CrossRefGoogle Scholar
  88. 88.
    Arbiol J, Cerda J, Dezanneau G, Cirera A, Peiro F, Cornet A, Morante JR (2002) Effects of Nb doping on the TiO2 anatase-to-rutile phase transition. J Appl Phys 92:853–861CrossRefGoogle Scholar
  89. 89.
    Seah MP (1990) Quantification of AES and XPS. In: Briggs D, Seah MP (eds) Practical surface analysis, vol 1, 2nd edn. Wiley, New York, pp 201–256Google Scholar
  90. 90.
    Simões JAM, Beauchamp JL (1990) Transition metal-hydrogen and metal-carbon bond strengths: the keys to catalysis. Chem Rev 90:629–688CrossRefGoogle Scholar
  91. 91.
    Anderson LC, Mooney CE, Lunsford JH (1992) Hydroxyl radical desorption from polycrystalline palladium: evidence for a surface phase transition. Chem Phys Lett 196:445–448CrossRefGoogle Scholar
  92. 92.
    Hashimoto S, Matsuoka H (1992) Prolonged lifetime of electrochromism of amorphous WO3–TiO2 thin films. Surf Interface Anal 19:464–468CrossRefGoogle Scholar
  93. 93.
    Hashimoto S, Matsuoka H (1991) Lifetime of electrochromism of amorphous WO3‐TiO2 thin films. J Electrochem Soc 138:2403–2408CrossRefGoogle Scholar
  94. 94.
    Sasaki K, Zhang L, Adzic RR (2008) Niobium oxide-supported platinum ultra-low amount electrocatalysts for oxygen reduction. Phys Chem Chem Phys 10:159–167CrossRefGoogle Scholar
  95. 95.
    Watanabe M, Motoo S (1975) Electrocatalysis by ad-atoms: Part II. Enhancement of the oxidation of methanol on platinum by ruthenium ad-atoms. J Electroanal Chem 60:267–273CrossRefGoogle Scholar
  96. 96.
    Davies JC, Hayden BE, Pegg DJ, Rendall ME (2002) The electro-oxidation of carbon monoxide on ruthenium modified Pt(1 1 1). Surf Sci 496:110–120CrossRefGoogle Scholar
  97. 97.
    Hadzi-Jordanov S, Angerstein-Kozlowska HA, Vukovic M, Conway BE (1978) Reversibility and growth behavior of surface oxide films at ruthenium electrode. J Electrochem Soc 125:1471–1480CrossRefGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Milan M. Jaksic
    • 1
    • 2
  • Angeliki Siokou
    • 1
  • Georgios D. Papakonstantinou
    • 1
  • Jelena M. Jaksic
    • 1
    Email author
  1. 1.Institute of Chemical Engineering Sciences, CEHT/FORTHPatrasGreece
  2. 2.Faculty of Agriculture, University of BelgradeBelgradeSerbia

Personalised recommendations