PNNL

Abstract

We have developed a low-temperature reflux method to synthesize large quantities of well-dispersed free-standing ZnO nanorods using a simple and mild aqueous solution route. In this approach, different surfactants were used to control nanostructure morphologies. Bound proton states in these ZnO nanorods were characterized for the first time by high resolution solid-state 1H magic angle spinning (MAS) NMR. In contrast to commercially available ZnO nano- or micro-particles, our uniform ZnO nanorods show a surprisingly sharp 1H NMR resonance. The feature is maintained upon heating to 500 oC, which suggests that an unusually stable proton species exists, most likely associated with lattice defects within the ZnO framework. Work here has demonstrated a new approach for probing a small amount of proton species associated with defects in nano-crystalline solids using high resolution solid-state 1H MAS NMR.