Interplay of nitrogen- and oxygen functionalities of carbon based catalysts in redox reactions

点击翻译按钮获取中文摘要

There is a long-standing interest on the catalytic properties of carbon materials. This interest has even been increased in the recent years due to the developments of novel applications for energy storage and conversion, respectively. Furthermore, carbon based catalysts are also discussed as an energy-saving alternative to long-standing used catalytic systems of the industrial chemistry. Nevertheless, up to date most of the examined carbon catalysts do not exhibit sufficient catalytic activity in a majority of studied reactions. Nitrogen doping of the carbons can enhance the activity for different redox reactions considerably. However, fundamental questions are still open and needed to be clarified, and from that the objectives of the project are derived. This concerns on the one hand the contribution of particular nitrogen functionalities to the catalytic functions and, on the other hand, the interaction of nitrogen and oxygen functionalities with each other as well. In this context, the impact of nitrogen functionalities on the formation of particular oxygen functionalities has to be considered, too. A modular concept of catalyst synthesis is required to investigate the matter. That concept shall be executed applying template assisted routes, which enable the formation of carbon replicas with controlled surface composition, structure and porosity. The catalysts will contain nitrogen functionalities with varied ratios of pyrrole- to pyridine-like species. The impact of the nitrogen species on the formation of oxygen functionalities will be investigated applying defined post treatments with oxidizing agents. The catalysts will be investigated in different test reactions such as the oxidative dehydrogenation of hydrocarbons, and the oxidation of sulphurous acid. The experimental findings shall be completed by quantum chemical calculations on the nature of nitrogen functionalities in model carbons. The prospective results of the submitted research project will provide a better understanding of the interplay of nitrogen and oxygen functionalities with each other in the examined reactions as well as improve a knowledge about new synthesis methods and possible catalytic applications of nitrogen-doped carbon materials.