An efficient procedure to bond nanostructured nitrogen functionalities to carbon surfaces

A new method for extensive and homogeneous functionalization of carbonaceous materials with nanostructured nitrogen functionalities is presented. The methodology employed uses a very effective and stable grafting of hyperbranched polyethyleneimines by covalent carboxamide bonds following a sequence of simple, mild, sustainable and easily scalable procedures. The key step in this methodology is the amidation by reaction of the terminal amino groups of the polyamines with methyl ester derivatives of carboxylic groups previously generated on the carbon surface. Through this approach, hybrid materials incorporating up to 8.45% of N in form of well defined, flexible, alkyl polyamine functions were obtained. Such hybrid materials, with nanostructured polyaminic functionalities on their surface, allow a further step towards a better understanding and controlling of chemical functionalization of carbon surfaces with complex organic molecules. The results shown can have important implications in the design and development of new hybrid functional materials of different kinds for targeted applications.