UC Riverside

The synthesis of novel nanomaterials systems and one-dimensioal nanostructures have created a great deal of excitement in the area of nanoelectronics and biomedical applications. The research presented in this dissertation is an effort to contribute to the realization of applications in both of the forementioned fronts of Nanotechnology.

In the first approach, a mutant icosahedral Cow Pea Mosaic Virus (CPMV) is employed as an scaffold to covalently attached two different types of inorganic nanomaterials; namely, ZnS(shell)/CdSe(core) semiconductor quantum dots and iron oxide (&gamma-Fe2O3) nanoparticles.

In the CPMV-QD(1,2) system a bistability behavior is observed and conductive atomic force microscopy (CAFM) is extensively used to characterize and implement a hybrid memory element at the nanoscale.

In the CPMV-&gamma-Fe2O3 system the conjugation of iron oxide (IO) nanoclusters is extensively characterized by magnetic force microscopy (MFM) and an increase in the local magnetic field strength opens up the potential use of this system in bioimaging applications.

On the second approach, crystalline nanowires (NWs) of semiconducting compound materials Copper Indium Disulfide (CuInS₂) and Indium Antimonide (InSb) are synthesized using a sono-electrochemical deposition process. Using sonoelectrochemistry overcomes many of the challenges related to the crystal quality that are inherent to regular electrochemistry and allows a greater control in the engineering of the electronic and optoelectrical properties of the as-synthesized NW

On one hand, CuInS₂ is a promising materials as an absorbent material for solar cell applications. During the synthesis process the effect of the partial precursor electrolyte ratios on the optoelectrical properties of the as-synthesized NWs is extensively study. As-synthesized I-rich NWs are found to be photoconductive while C-rich NWs are not.

On the other hand, InSb is an attractive material to develop high speed and low power logical applications. During the synthesis process, the depositon potential was selectively controlled as a way to modify the composition and stoichiometric ratio of the as-synthesized NWs. The transport characteristics of as-synthesized NWs were modified between n and p-type semiconducting behavior.