In various embodiments, the present disclosure describes fullerene derivatives that are capable of photocatalytically generating reactive oxygen species in the presence of ultraviolet and/or visible light. In some embodiments, the fullerene derivatives are aminofullerenes containing a plurality of amine-terminated moieties covalently bonded to the fullerene cage. The fullerene derivatives may optionally be covalently bonded to a substrate surface for use in photocatalytic disinfection systems for removing various contaminants including, for example, bacteria, viruses, protozoa and chemical pollutants. Methods using the present fullerene and aminofullerene derivatives in various purification processes are also described herein.