Chemically induced potential barriers at the carbon nanotube-metal nanoparticle interface.

Single-walled carbon nanotube (SWNT) field effect transistors were electrochemically decorated with Pt, Pd, Au, and Ag nanoparticles. Upon exposure to 10 ppm NO gas in N2 a trend was found wherein the magnitude of electron transfer into the SWNT valence band scaled with the work function of the individual metal. This trend gives experimental support for the formation of a metal work function dependent potential barrier at the SWNT--nanoparticle interface.