Small makes things better. When matters are reduced in size to the nanometer scale (0.2-100 nm), they tend to have new properties compared to their bulk materials, and potentially impose powerful or novel functions on devices and systems. Toward this goal, generation of nanomaterials and/or nanostructures in a large scale is substantially desired for the revolution of pragmatic applications. Below are the application-directed research topics in the Functional Advanced Nanostructured Film Laboratory (FANFL):
- Silicon nanowires (SiNWs)
Wet chemical etching is a simple and cheap approach to produce silicon nanowires in the wafer scale. A range of material parameters can be flexibly controlled, including doping level, dopant material, crystallographic orientation, length and surface topography. This method will be adopted to generate SiNWs for the application in photocatalysis, photovoltaics, optoelectronics and hydrogen storage.
- Metal nano-films:
Surface enhanced Raman spectroscopy (SERS) has been widely studied for bio-diagnostics, due to the extremely high detection sensitivity and compatibility with aqueous bio-environment. However, the commercialization of this technique is substantially limited by the lack of the substrates with reliable and reproducible detection sensitivity. Noble metals (gold and silver) are commonly used for SERS. In the FANFL, glancing angle physical vapor deposition (GLAPVD) will be employed to generate noble metal nanostructured film on the commercialized hard and flexible substrates. Control over the shape, film thickness and surface spacing will be systematically carried out to optimize the SERS detection sensitivity, uniformity and reliability, and production reproducibility.
- Nonmetal nano-films:
The GLAPVD technique enables one to flexibly engineer the film materials (such as semiconducotrs and oxides) and morphology (shape, periodicity, surface porosity, pitch size and growth orientation). The engineering will be demonstrated in the FANFL. Structures and physical properties of the nonmetal nanofilms will be explicitly characterized, and application in solar energy conversion, clean fuel generation and self-cleaning will be studied.