Electrochemical chlorine evolution at rutile oxide (110) surfaces.

Based on density functional theory (DFT) calculations we study the electrochemical chlorine evolution reaction on rutile (110) oxide surfaces. First we construct the Pourbaix surface diagram for IrO(2) and RuO(2), and from this we find the chlorine evolution reaction intermediates and identify the lowest overpotential at which all elementary reaction steps in the chlorine evolution reaction are downhill in free energy. This condition is then used as a measure for catalytic activity. Linear scaling relations between the binding energies of the intermediates and the oxygen binding energies at cus-sites are established for MO(2) (M being Ir, Ru, Pt, Ti). The linear relations form the basis for constructing a generalized surface phase diagram where two parameters, the potential and the binding energy of oxygen, are needed to determine the surface composition. We calculate the catalytic activity as function of the oxygen binding energy, giving rise to a Sabatier volcano. By combining the surface phase diagram and the volcano describing the catalytic activity, we find that the reaction mechanism differs depending on catalyst material. The flexibility in reaction path means that the chlorine evolution activity is high for a wide range of oxygen binding energies. We find that the required overpotential for chlorine evolution is lower than the overpotential necessary for oxygen evolution.

[1]  H. Monkhorst,et al.  SPECIAL POINTS FOR BRILLOUIN-ZONE INTEGRATIONS , 1976 .

[2]  José L. Fernández,et al.  Kinetic study of the chlorine electrode reaction on Ti/RuO2 through the polarisation resistance: Part I: experimental results and analysis of the pH effects , 2002 .

[3]  S. Trasatti,et al.  Surface and electrocatalytic properties of well-defined and vicinal RuO2 single crystal faces , 2005 .

[4]  Thomas Bligaard,et al.  The Brønsted–Evans–Polanyi relation and the volcano curve in heterogeneous catalysis , 2004 .

[5]  A. Gross,et al.  Tuning catalytic properties of bimetallic surfaces: Oxygen adsorption on pseudomorphic Pt/Ru overlayers , 2007 .

[6]  W. O'grady,et al.  Chlorine Evolution and Reduction Processes at Oriented Single‐Crystal RuO2 Electrodes , 1986 .

[7]  Manos Mavrikakis,et al.  Improved oxygen reduction reactivity of platinum monolayers on transition metal surfaces , 2008 .

[8]  J. Nørskov,et al.  Universality in Heterogeneous Catalysis , 2002 .

[9]  J Rossmeisl,et al.  Estimations of electric field effects on the oxygen reduction reaction based on the density functional theory. , 2007, Physical chemistry chemical physics : PCCP.

[10]  Egill Skúlason,et al.  Modeling the electrified solid-liquid interface , 2008 .

[11]  D. Vanderbilt,et al.  Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. , 1990, Physical review. B, Condensed matter.

[12]  A. Panchenko,et al.  Ab Initio calculations of intermediates of oxygen reduction on low-index platinum surfaces , 2004 .

[13]  R. A. Santen,et al.  Periodic Density Functional Study of CO and OH Adsorption on Pt−Ru Alloy Surfaces: Implications for CO Tolerant Fuel Cell Catalysts , 2002 .

[14]  Manos Mavrikakis,et al.  Reactivity descriptors for direct methanol fuel cell anode catalysts , 2008 .

[15]  S. Trasatti.  Electrocatalysis in the anodic evolution of oxygen and chlorine , 1984 .

[16]  J. Nørskov,et al.  Comparing Electrochemical and Biological Water Splitting , 2007 .

[17]  J. Goodenough.  Electrodes of Conductive Metallic Oxides , 1982 .

[18]  Y. Pankratiev.  Correlation between oxygen binding energy and catalytic activity of oxides , 1982 .

[19]  J. Nørskov,et al.  Electrolysis of water on (oxidized) metal surfaces , 2005 .

[20]  C. Iwakura,et al.  Some oxide catalysts for the anodic evolution of chlorine: reaction mechanism and catalytic activity , 1978 .

[21]  A. Kuhn,et al.  The Kinetics of Chlorine Evolution and Reduction on Titanium‐Supported Metal Oxides Especially RuO2 and IrO2 , 1973 .

[22]  Sergio Trasatti,et al.  Electrocatalysis: understanding the success of DSA® , 2000 .

[23]  H. Jónsson,et al.  Origin of the Overpotential for Oxygen Reduction at a Fuel-Cell Cathode. , 2004, The journal of physical chemistry. B.

[24]  J. Nørskov,et al.  Electrolysis of water on oxide surfaces , 2007 .

[25]  J. Nørskov,et al.  Improved adsorption energetics within density-functional theory using revised Perdew-Burke-Ernzerhof functionals , 1999 .

[26]  J. Nørskov,et al.  Steady state oxygen reduction and cyclic voltammetry. , 2008, Faraday discussions.

[27]  L. I. Krishtalik.  Kinetics and mechanism of anodic chlorine and oxygen evolution reactions on transition metal oxide electrodes , 1981 .

[28]  C. J. Weststrate,et al.  Stable deacon process for HCl oxidation over RuO2. , 2008, Angewandte Chemie.

[29]  Ture R. Munter,et al.  Scaling properties of adsorption energies for hydrogen-containing molecules on transition-metal surfaces. , 2007, Physical review letters.

[30]  J. Nørskov,et al.  Towards the computational design of solid catalysts. , 2009, Nature chemistry.

[31]  J. Nørskov,et al.  Scaling relationships for adsorption energies on transition metal oxide, sulfide, and nitride surfaces. , 2008, Angewandte Chemie.

[32]  Faraday Discuss , 1985 .

[33]  J. Nørskov,et al.  Modeling the electro-oxidation of CO and H2/CO on Pt, Ru, PtRu and Pt3Sn , 2003 .

[34]  A. Wiȩckowski,et al.  Mechanisms of methanol decomposition on platinum: A combined experimental and ab initio approach. , 2005, The journal of physical chemistry. B.

[35]  Jens K Nørskov,et al.  Surface Pourbaix diagrams and oxygen reduction activity of Pt, Ag and Ni(111) surfaces studied by DFT. , 2008, Physical chemistry chemical physics : PCCP.

[36]  N. López,et al.  Mechanism of HCl oxidation (Deacon process) over RuO2 , 2008 .