Orthorhombic molybdenum trioxide (alpha-MoO3) nanorods have been synthesized on a large scale by a hydrothermal method for electrochemical energy storage supercapacitor devices. The electrochemical properties of nanorods synthesized at different temperatures were investigated using cyclic voltammetry. The effects of synthesis temperature, scan rate and different scan cycles on the cyclic voltammograms were systematically studied. Nanorods synthesized at 180 degrees C for 6 h show the best electrochemical properties compared to those synthesized at other temperatures. (C) 2010 Elsevier Ltd. All rights reserved.