The substrate assisted doping of ZnO nanowires grown by a vapor transport technique was reported. The nanowires were grown non-catalytically on multi-walled carbon nanotubes and soda lime glass. Carbon from the nanotubes and sodium from soda lime glass diffused into ZnO during the growth and were distributed uniformly and provide doping. An advantage associated with the technique was that no conventional external dopant source was required to obtain doped ZnO nanowires. The diameter, length and hence the aspect ratio could easily be varied by changing the growth conditions. The transport studies of both carbon and sodium doped ZnO supported the p-type nature of ZnO. The p-type nature of carbon doped ZnO was stable for at least eight months.

Doping by Diffusion of Dopants from the Substrate: Synthesis of Doped ZnO Nanowires. Sugavaneshwar, R.P., Goswami, G.K., Nanda, K.K.: Journal of Materials Chemistry C, 2013, 1[6], 1066-9