We report the synthesis of CuO-loaded SnO2 nanofibers via electrospinning as well as their H2S sensing properties in a comparative manner with unloaded, pure SnO2 nanofibers. Greatly enhanced H2S sensing capability was observed by loading a trace amount of CuO into SnO2 nanofibers. At 10 ppm H2S, the CuO-loaded SnO2 nanofibers showed a response of 1.98 x 10(4) and response and recovery times of 1 and 10s, respectively. In addition, the CuO-loaded SnO2 nanofibers showed outstanding selectivity to H2S. Along with the unique sensing mechanism based on the creation and disruption of p-n junctions, the high specific surface area provided by the one-dimensional nanofiber shape and the facilitation of p-n junctions due to the presence of nanograins are responsible for the outstanding H2S sensing capability observed in the CuO-loaded SnO2 nanofibers. (C) 2012 Elsevier B.V. All rights reserved.