Gold was successfully deposited on multiwall carbon nanotubes (MWNTs). It was achieved by applying a gold colloid stabilised by [tetrakis(hydroxymethyl)phosphonium chloride] (THPC) surfactant and ultrasonic irradiation during preparation. By controlling the quantity of gold and optimising sonication time up to 50 wt% gold could be deposited on MWNTs. (C) 2003 Elsevier Science B.V. All rights reserved.