Pt/SnO(2) core-shell nanowires were prepared by a process that involves thermal evaporation of SnO(2) nanowires and subsequent atomic layer deposition of Pt, and their gas- and photon-sensing properties were investigated systematically. Transmission electron microscopy analysis showed that the Pt shell with a thickness of 8.8 nm is composed of numerous Pt nanoparticles with average diameters of similar to 5.3 nm. The Pt/SnO(2) core-shell nanowires with high electrical conductance exhibit remarkably enhanced ethanol gas-and photon-sensing properties due to the surface functionalization resulting from the effective Pt catalyst and the formation of hetero-nanostructures fabricated by the SnO(2) core and Pt shell. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3464800] All rights reserved.