Novel magnetically recyclable carbon nanocomposites were synthesized to support various nanocatalysts using a simple, economical and scalable method. The designed nanocomposites, which are composed of porous carbon and Fe3O4 nanocrystals, can be used as an expandable platform to load versatile nanopartide catalysts such as Pd and Pt. These nanocomposites with high surface area and permeable porous structure can contain abundant and accessible small-sized catalyst nanoparticles. These characteristics led to efficient catalytic reactions and enhanced catalytic activity, which were verified in selective reduction of nitroarenes and Suzuki cross-coupling reactions. The nanocomposite catalysts provided excellent catalytic activities to yield the desired products in short reaction time and mild reaction conditions. The catalysts could be easily separated from the reaction mixture by a magnet, and recycled five consecutive cycles in reduction of nitrobenzene and Suzuki cross-coupling of bromobenzene without losing significant activities. (C) 2014 Elsevier B.V. All rights reserved,