title: An understanding and implications of the coverage of surface free sites in heterogeneous catalysis.
abstract: The crucial roles of the coverage of surface free sites in determining catalytic activity trend are quantitatively addressed with the help of density functional theory and microkinetics. First, by analyzing activity trends of NO oxidation catalyzed by Ru, Rh, Pd, Os, Ir, and Pt surfaces with full kinetic considerations, we identify that the activity trend is in general determined by the competition between the reaction barrier and the coverage of surface free sites. Second, since the dissociation of many important molecules, such as the dissociation of N(2), O(2), and CO, follows the same Bronsted-Evans-Polanyi relationship, the coverage of surface free sites is usually a decisive term that affects the overall activity. Third, an equation is derived for the coverage of surface free sites and it is found that the coverage of surface free sites contains not only all the key thermodynamic parameters but also all the kinetic properties in the catalytic system.
authors.affiliation: Labs for Advanced Materials, Research Institute of Industrial Catalysis, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Wang
authors.forename: Yanglong
authors.initials: Y
authors.lastname: Guo
authors.forename: Guanzhong
authors.initials: G
authors.lastname: Lu
authors.forename: P
authors.initials: P
authors.lastname: Hu