Gold and Zinc Oxide Nanoparticle Coated Peptide Nanotubes Fabrication and Their Electrical Transport Properties Study.

摘要

There is a growing interest in attempts in using biomolecular as the 1D nanotube templates to grow inorganic nanoparticles (NPs) in controlled morphology and structure. One of the research motivations for this combination is to take advantage of the catalytic activity for the room-temperature material growth and the ability of self-assembly into controlled structures on a large scale. One approach to fabricate such nanotube is by using a glycine-based peptide nanotube as template, and on template sidewall immobilizing biomineralizing peptide, which can selectively bind to the target metal/semiconductor precursor and mediate the formation of the inorganic material on templates incorporating these peptides.;By optimizing the experiment conditions, we successfully fabricated high yield of nanotubes with full coverage of high-density monodispersed Au and ZnO NPs coating. Using drop casting technique, we built electronic device with these nanotubes and found very interesting electrical transport properties: the temperature-dependent current-voltage characteristic of Au NPs nanotube; and the negative differential resistance property (current decreases with increasing bias voltage) of ZnO NPs coated nanotube. These results are of great impact on the future development of bio-nanoelectronic devices.;Besides, a new biomimetic approach for one-pod synthesis of ZnO nanotube at neutral pH and room temperature is introduced; by self-assembling peptides which possess the catalytic mineralization function for the specific oxide metal, ZnO nanotube can be grown as the peptides are simultaneously assembled into a rod structure and template ZnO growth in gels formed by the peptides and Zn precursors. Traditionally, biomineralizing peptides are coated on 1D templates and then grow ZnO at room temperature, however this new method allows one to grow ZnO nanotubes in one step without using 1D templates since the Zn-mineralizing peptide itself can be assembled into the 1D structure.