Reactivity Theory of Transition-Metal Surfaces: A Bronsted-Evans-Polanyi Linear Activation Energy-Free-Energy Analysis
ABSTRACT A study was conducted to demonstrate the application of the Brønsted-Evans-Polanyi (BEP) relationship in the analysis of surface elementary reaction steps. The BEP equation directly related the change in activation energy of the reaction, δEact to the corresponding change of the reaction energy, δEr for different surfaces through a constant factor α. The activation energy was deduced from the reaction energy, which was a thermodynamic parameter. An analytic derivation of the BEP equation was presented using a Marcus-type analysis to provide a conceptual frame for the discussion. The physical chemistry of the surface reaction was viewed as a potential-energy curve crossing problem. It was found that surface electronic factors required a modification of this simple potential-energy crossing model.
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- "By combining chemical catalysis and electrochemical reactions , electrocatalysis controls a number of reaction conditions through voltage and current regulation, thus achieving higher catalytic efficiency  . In electrocatalysis, electrodes with high electrocatalytic activities, such as Pt, Ti/PbO 2 , BDD, and Ti/TiO 2 electrodes, have been used in the electrochemical catalytic degradation of organic pollutants    . "
ABSTRACT: TiO2-NTs-based Sb-SnO2 electrode with three-dimensionally sphere-stacking structure was successfully fabricated by the solvothermal method, followed by annealing at 500 °C for 1 h. The physico-chemical properties of electrodes were characterized through scanning electron spectroscopy (SEM), X-ray diffraction (XRD) and electrochemical measurements. SEM result showed that TiO2-NTs/Sb-SnO2 electrode has morphology of vertically sphere-stacking coralline. Compared with Ti/Sb-SnO2, TiO2-NTs/Sb-SnO2 electrode has smaller grain size and greater specific surface area which can provide with more active sites. Compared with Ti/Sb-SnO2 electrode, TiO2-NTs/Sb-SnO2 has a higher oxygen evolution potential and stronger phenol oxidation peak, indicating an improved catalytic activity for phenol degradation. The kinetic analysis of electrochemical phenol degradation showed that the first-order kinetics rate constant on TiO2-NTs/Sb-SnO2 electrode is 1.33 times as much as that on Ti/Sb-SnO2, confirming that the sphere-stacking Sb-SnO2 based on TiO2 nanotube has a good electrocatalytic activity.Ceramics International 08/2015; 41(7):8723-8729. DOI:10.1016/j.ceramint.2015.03.092 · 2.09 Impact Factor
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- "For example, Pt and other group VIII metals are known to be very active for fuel cells, automotive exhaust, hydrogenolysis, and hydrogenation catalysis . Group VIII metals are often present in heterogeneous catalysis and electrocatalysis as a result of the well-established Sabatier's principle which suggests that the metals in middle of the periodic table demonstrate optimal metal-adsorbate bond strengths necessary to drive surface reactivity and still allow product desorption     . "
ABSTRACT: In this report, we discuss some of the advances in surface science and theory that have enabled a more detailed understanding of the mechanisms that govern the electrocatalysis. More specifically, we examine in detail the electrooxidation of C-1 and C-2 alcohol molecules in both acidic and basic media. A combination of detailed in situ spectroscopic measurements along with density functional theory calculations have helped to establish the mechanisms that control the reaction paths and the influence of acidic and alkaline media. We discuss some of the synergies and differences between electrocatalysis and aqueous phase heterogeneous catalysis. Such analyses begin to establish a common language and framework by which to compare as well as advance both fields. (C) 2012 Elsevier B.V. All rights reserved.Catalysis Today 03/2013; 202(1). DOI:10.1016/j.cattod.2012.08.013 · 3.31 Impact Factor
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ABSTRACT: An optimum reaction path for CO activation is an important issue in the Fischer-Tropsch synthesis for the production of liquid hydrocarbons from syngas. In the present theoretical study, we show that the CO activation on open Ru and Co surfaces consisting of active six-fold sites is initiated through the carbide mechanism instead of the hydrogen assisted pathway.Physical Chemistry Chemical Physics 06/2010; 12(24):6330-2. DOI:10.1039/b926731j · 4.20 Impact Factor