Pd nanoparticles immobilized on magnetic carbon dots@Fe3O4 nanocubes as a synergistic catalyst for hydrogen generation

In this work, a cube-like Pd/carbon dots Fe3O4 (Pd/C-dots Fe3O4) hybrid material has been successfully prepared through a facile ultrasonic assisted chemical reduction method, and used as a highly efficient catalyst for the hydrolytic dehydrogenation of NaBH4 in alkaline media. It is found that the small Pd nanoparticles (NPs) are uniform and well dispersed on the surface of C-dots Fe3O4 nanocubes (NCs). Benefiting from the advantages of the unique cube-like structure, the super conductivity of carbon dots (C-dots) and the synergistic effect between Pd NPs and C-dots@Fe3O4 support, Pd/C-dots Fe3O4 NCs exhibits the highest catalytic performance among all the as-prepared samples. The possible reaction mechanism is discussed. Furthermore, the effects of reaction temperature, NaBH4 concentration and NaOH concentration on the catalytic activity of Pd/C-dots@Fe3O4 NCs are studied. Besides, the magnetic properties of Pd/C-dots@Fe3O4 NCs can achieve effective momentum transfer with the assistance of the external magnetic field, and a higher catalytic activity is observed for Pd/C-dots Fe3O4 NCs in self-stirring mode than in magnetic stirring mode. This novel catalyst also exhibits good stability and can be easily separated by a magnet, showing great potential for renewable energy applications. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.