Au催化水煤气变换反应的密度泛函理论研究

应用密度泛函理论(DFT)对Au催化水煤气变换反应的3种可能机理(氧化还原机理、羧基机理、甲酸根机理)进行比较。通过对各个基元反应的反应物、反应中间体、过渡态和产物的研究表明:水煤气变换反应在Au(111)面有3种可能机理,并且每种机理各有2种反应途径.对氧化还原机理来说,反应易按照2个OH的歧化反应进行:对羧基机理来说,反应易按照COOH和OH发生歧化反应进行;对甲酸根机理来说,反应易按照HCOO和OH反应进行。纵观整个反应历程,从活化能比较可知,按甲酸根机理进行的可能性最小,按照羧基机理反应的可能性最大。

Density functional theoretical study on Au-catalyzed water gas shift reaction

Three possible mechanisms,namely,redox mechanism,carboxyl mechanism,and formate mechanism,of the water-gas shift reaction catalyzed by Au were studied and compared using density functional theory.By studying the reactants,intermediates,transition states, and products of each fundamental reaction,it was shown that there exist three possible reaction mechanisms for the reaction,and two possible reaction pathways for each mechanism.From the comparison of the activation energies,it can be concluded that the possibility of formate mechanism is minimal,while carboxyl mechanism is the most likely.