In this work, we explore the electrospinning of polyacrylonitrile (PAN)/zinc(II) chloride (ZnCl2) composite nanofibers and the response of these nanofibers to hydrogen sulfide (H2S). Solution properties, including surface tension, viscosity, and conductivity, have been measured and integrated with the results of a variety of other analytical techniques to investigate the effects of ZnCl2 salt on the structure and thermal properties of electrospun nanofibers. It is found that the addition of ZnCl2 reduces the diameter and inhibits the instantaneous cyclization reaction of these nanofibers. Additionally, exposing PAN/ZnCl2 fibers to H2S leads to the formation of PAN/zinc sulfide (ZnS) composite nanofibers that contain ZnS crystals on the surface. These results indicate that PAN/ZnCl2 composite nanofibers could find applications in H2S sensing and removal, or as precursors for semiconductor ZnS-coated polymer nanofibers. (C) 2008 Elsevier Ltd. All rights reserved.