Single ZnO nanowires coated with Pt clusters by sputtering are shown to selectively detect hydrogen at room temperature. There were no differences in the current-voltage characteristics for measurement in air, N-2, or vacuum. The single nanowires operate at extremely low power levels of similar to 15-30 mu W, which is approximately a factor of 25 lower than multiple ZnO nanowires operated under the same conditions. The addition of the Pt coatings increased the detection sensitivity of the nanowires for 500 ppm H-2 in N-2 by approximately an order of magnitude, which is about a factor of two improvement over the similar case for multiple nanowires. Pt-coated single ZnO nanowires showed relative responses of similar to 20% and 50%, respectively, after 10 or 20 min exposure, respectively, to 500 ppm H-2 in N-2. (c) 2005 The Electrochemical Society.