Long and spinnable carbon nanotube (CNT) arrays have been synthesized through a chemical vapor deposition process using the Fe/Al2O3 on a silicon substrate as the catalyst, ethylene as the carbon source, and an Ar/H-2 mixture gas as the carrying gas. CNT fibers are then spun from the high-quality arrays with excellent mechanical and electrical properties. The CNT fibers have been further used as electrodes to fabricate a family of novel dye-sensitized solar cells with high potentials. (C) 2011 Elsevier B.V. All rights reserved.