To improve the utilization and activity of anodic catalysts for direct methanol fuel cells, multi-walled carbon nanotube (MWCNT) is used as a support for platinum (Pt) nanoparticles synthesized by method of ultraviolet irradiation. MWCNT is modified by methylene blue (f(0)-MWCNT) under ultraviolet light (f(1)-MWCNT), and then Pt nanoparticles are assembled on the f(1)-MWCNT to form composites (Pt/f(1) MWCNT). Fourier transform infrared spectroscopy analysis reveals that the surface of MWCNT is successfully functionalized. Transmission electron microscopy and X-ray diffraction analyses exhibit that the uniformly dispersed Pt nanoparticles of around 2.5 nm in size are obtained. Cyclic voltammetric and chronoamperometric experiments demonstrate that the as-prepared Pt/f(1)-MWCNT composites show higher catalytic activity and better stability compared with Pt/f(0)-MWCNT and commercial Pt/C (JM), which is vital to anode electrocatalysis in direct methanol fuel cells. (C) 2012 Elsevier B.V. All rights reserved.