In Situ Growth of Fe2O3 Nanoparticles on Highly Porous Graphene/Polyimide-Based Carbon Aerogel Nanocomposites for Effectively Selective Detection of Dopamine

It is very important to develop a simple, efficient, and scaleable method for detection of dopamine (DA) with high sensitivity and selectivity to diagnose some serious neurological diseases. Herein, electro-catalysts for detection of DA are simply prepared based on Fe2O3 nanoparticles (NPs) decorated on highly porous carbon aerogels (CAs), which are derived from KOH activated graphene-polyimide aerogels. In the hierarchical nanocomposites (NCs), CAs provide large specific surface area, abundant mesopores, and macropores, and many sites for in situ growth of Fe2O3 NPs, thus effectively preventing the aggregation of Fe2O3 NPs. Moreover, CAs with 3D interconnected porous structures are able to shorten the charge transfer pathways through the intimate interaction between CAs and Fe2O3 NPs. Therefore, when applied as electro-catalysts for detection of DA, the optimized NC exhibits rapid amperometric response and a low detection limit of 0.109 x 10(-6) M (S/N = 3), with a wide linear concentration range from 5 to 500 x 10(-6) M. In addition, the oxidation peak of DA can be readily distinguished from the interference of uric acid and ascorbic acid. Therefore, the highly porous CAs derived from KOH activated graphene-polyimide aerogels are excellent substrates for in situ growth of Fe2O3 NPs, exhibiting high electrocatalytic activity for DA detection.