WATER-ASSISTED GROWTH OF NANOFLORETS HYBRID NANOSTRUCTURES AND THEIR APPLICATION IN SENSING PLATFORMS

摘要

Self-processing (SP) is typically recognized in the context of biological systems. For example, proteins and RNA molecules undergo SP, which includes chemical and structural modifications. Recently, we developed a new strategy for the synthesis of metal-semiconductor hybrid nanostructures relying on self-processing mechanism which yield complex hybrid nanostructures in one step by triggering a programmable cascade of events that is autonomously executed. The semiconductor-metal hybrid nanostructures obtained resemble the morphology of grass flowers, termed here Nano-floret. Interestingly, water are used during the 'growth' process of Nano-florets as a mild etchant for synthesis intiation and progression. The synthesis mechanism was directly followed by in situ and ex situ scanning transmission electron microscopy and inductively coupled plasma mass spectrometry analyses. Our results indicate that distinct processing steps including localized oxide etch and metal deposition and process termination can be identified similarly to conventional top-down processing sequences. The Nano-floret hybrid nanostructures were used for fabrication of sensors featuring a self-forming nanojunction. A main feature of the device is a self-formed nanogap bridging between the Nanofloret (NF) hybrid nanostructures (HNS) and a macroscopic counter-electrode which enables direct detection of molecules and quantum dots, including their electronic fingerprint.