NO oxidation over nitrogen doped carbon xerogels

Carbon xerogels were prepared from a nitrogen-containing polymer precursor, using melamine and urea as nitrogen sources incorporated into the polymer matrix, by the sol–gel process. Materials with different contents of nitrogen were obtained and used as catalysts for NO oxidation at room temperature. The NO conversions obtained with nitrogen doped carbon xerogels were quite high, showing that carbon xerogels are efficient catalysts for NO oxidation. A maximum of 88% conversion for NO was obtained at NO initial concentration of 1000 ppm and 20% of O2. The presence of nitrogen-containing surface groups was shown to favour the oxidation of NO to NO2. The catalytic activity of the catalysts is maintained in consecutive runs.

The presence of pyridine (N6) and pyrrole (N5) groups in N-doped carbon xerogels favours the oxidation of NO.Figure optionsDownload as PowerPoint slideHighlights
► Nitrogen-doped carbon xerogels were prepared using melamine and urea.
► The materials performed well as catalysts for NO oxidation at room temperature.
► The catalytic activity of the catalysts was maintained in consecutive runs.
► The presence of pyridine and pyrrole groups favours the oxidation of NO.
► The presence of surface oxygen inhibits NO oxidation.