Selective catalytic reduction of NOχ by H2 in the presence of oxygen has been investigated over Pt/ A12O3 catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence ...Selective catalytic reduction of NOχ by H2 in the presence of oxygen has been investigated over Pt/ A12O3 catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence on the catalytic performance, and the catalyst pre-treated by HE or H2 then followed by O2 is much more active than that pre-treated by air. The higher surface area and the presence of metallic Pt over Pt/A12O3 pre-treated by HE or pretreated by H2 then followed by O2 can contribute to the formation of NO2, which then promotes the reaction to proceed at low temperatures.展开更多
Understanding the fundamental mechanisms for charge transfer in supported catalysts is of great importance for heterogeneous catalysis. Several experimental and theoretical results suggest that charge flow through met...Understanding the fundamental mechanisms for charge transfer in supported catalysts is of great importance for heterogeneous catalysis. Several experimental and theoretical results suggest that charge flow through metal-support interfaces leads to the catalytic enhancement that is often observed in mixed catalysts. Therefore, it is crucial to directly probe this charge flow in metal-support catalysts during catalytic reactions. In this review, we consider the main aspects of research studying the processes that create and allow interfacial transfer of highly excited（hot） charge carriers in supported catalysts, and discuss the effect of this charge transfer on catalytic activity. We show a close connection between the phenomena of hot electron creation and chemical energy dissipation that accompanies catalytic reactions at both the gas/solid and liquid/solid interfaces. The intensity of hot electron flow is well correlated with the turnover rates of corresponding reactions, which opens up the possibility for developing new operando methodologies for studying chemical processes on catalytic surfaces.展开更多
文摘Selective catalytic reduction of NOχ by H2 in the presence of oxygen has been investigated over Pt/ A12O3 catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence on the catalytic performance, and the catalyst pre-treated by HE or H2 then followed by O2 is much more active than that pre-treated by air. The higher surface area and the presence of metallic Pt over Pt/A12O3 pre-treated by HE or pretreated by H2 then followed by O2 can contribute to the formation of NO2, which then promotes the reaction to proceed at low temperatures.
基金supported by the Institute for Basic Science (IBS, Republic of Korea) (No. IBS-R004-A2-2017-a00)
文摘Understanding the fundamental mechanisms for charge transfer in supported catalysts is of great importance for heterogeneous catalysis. Several experimental and theoretical results suggest that charge flow through metal-support interfaces leads to the catalytic enhancement that is often observed in mixed catalysts. Therefore, it is crucial to directly probe this charge flow in metal-support catalysts during catalytic reactions. In this review, we consider the main aspects of research studying the processes that create and allow interfacial transfer of highly excited（hot） charge carriers in supported catalysts, and discuss the effect of this charge transfer on catalytic activity. We show a close connection between the phenomena of hot electron creation and chemical energy dissipation that accompanies catalytic reactions at both the gas/solid and liquid/solid interfaces. The intensity of hot electron flow is well correlated with the turnover rates of corresponding reactions, which opens up the possibility for developing new operando methodologies for studying chemical processes on catalytic surfaces.
