Abstract: In order to prepare stable and reusable heterogeneous catalysts, palladium nanop articles were supported on platlet carbon nanofiber (pCNF), fishbone carbon nano fibers (fCNF) and tubular carbon nanofibers (tCNF). It was found that the Pd loa ding and particle size as well as the amount of Pd leaching during the Heck reaction were strongly related to the potential difference between the CNF surf aces and the palladium colloids. Pd leaching in the Heck reaction can be signifi cantly suppressed by increasing potential difference between the CNF surfaces an d the palladium colloids during catalyst preparation. The Pd activity decreased exponentially with the Pd size.

Key words: carbon nanofiber, palladium, point of zero charge, Heck reaction, heterogeneous catalyst