A facile method of modifying graphite powder with aminophenyl groups in bulk quantities

A facile and rapid method of covalently modifying the surface of graphite powders with aminophenyl groups is described. This chemical modification strategy allows the production of bulk (gram) quantities of amino-modified carbon powder. 4-Nitrophenyl groups are covalently attached to graphite powder via the chemical reduction of the corresponding 4-nitrobenzenediazonium tetrafluoroborate salt using aqueous hypophosphorous acid. The 4-nitrophenyl groups on the carbon surface are then reduced to the corresponding 4-aminophenyl groups using alkaline iron(II) ammonium sulfate solutions. Electrochemical and X-ray photoelectron spectroscopic characterisation is carried out at each stage of the synthesis.