Sputtered platinum nanocluster growth on previously plasma enhanced chemical vapor deposition PECVD - grown vertically aligned carbon nanofiber arrays is presented. Experimental cluster size distribution is shown to decrease from the CNF top to bottom, as observed by transmission electron microscopy. Molecular dynamics simulations are carried out for understanding early stages of Pt growth on model CNF arrays. Especially, sticking coefficients, concentration profiles along CNF wall, cluster size distributions are calculated. Simulated cluster size distribution are consistent with experimental finding. Sticking coefficient decreases against deposition time. The shape of the sticking curve reflects the nanocluster growth process. (C) 2012 Elsevier B. V. All rights reserved.