| Recent advances in nanotechnology have resulted in development of a wide array of novel nanomaterials for various applications. Nano-particles, rods, wires, tubes and other geometrical forms have attracted great interest due to their unique shape and size-dependent properties at the nanometer scale. In addition to their applications in electronics and catalysis, such nanomaterials have also been employed as barcodes in various biological and non-biological systems, as engines for autonomous locomotion, and in novel or existing sensing platforms. Despite the encouraging progress during the recent years, there are significant challenges in fabrication and in meeting the demands for higher performance materials. In this dissertation, advances in the fabrication, use and performance of various nanostructures in barcoding, locomotion and biosensing, applications and their implications were discussed. A rapid, single-step alloy electrodeposition scheme was developed to fabricate compositionally encoded nanowire barcodes. It was shown that multiple readout techniques can be used to decode the barcode patterns in an orthogonal manner as most nanobarcodes to present day have relied on segmented growth approaches and a single level of identification. On another front, the speed of autonomous gold/platinum (Au/Pt) catalytic nanomotors was enhanced by an order of magnitude and the power output was increased by two orders of magnitude by using a cathodic silver/gold (Ag/Au) alloy instead of a pure Au segment. Nanomotor speeds were found to correlate with the Ag content in the alloy, and possible mechanisms behind this enhancement were discussed. A novel use of nanoparticles for biosensing applications was also demonstrated. It was shown that electrochemical impedance responses of biomarkers can be tuned by gold nanoparticles (AuNP) for frequency-based detection. The system's impedance behavior was characterized by physical, electrical and mathematical models, and the theory and mechanisms behind the tuning process were discussed. |
