Synthesis of magnesium oxide (MgO) nanorods was achieved by simply heating MgCl2 powder at 750 degreesC for 1.5 h in a constant flow of mixture gas (90% pure argon and 10% pure hydrogen). Transmission electron microscopy (TEM) morphology and energy-dispersive X-ray spectrometry (EDX) analysis showed that the product is mainly composed of MgO nanorods with diameters of 15 to 50 nm, and lengths ranging from 1 to 3 micrometers. After the MgO nanorods were incorporated into (Bi, Pb)-2223 superconductor, the critical current densities (Jc's) of the nanorod-superconductor composites are significantly enhanced. (C) 2000 Elsevier Science Ltd. All rights reserved.