Woong Kim
Korea University Sejong, South Korea
Title: Biomimetic fabrication technique of nano materials mixed micro wire for sensing nitrogen dioxde molecules
Biography
Biography: Woong Kim
Abstract
Researches on the new materials by using polymers and nanomaterials have spotlight recently, because of availability to use it sensors in smart vehicle. Among the various polymers, representatively, PVP (Polyvinylpyrrolidone) is the most famous polymer, because of non-toxicity and human-friendly. So, it has been used not only commercial glue but also the various research areas. We focused on how spiders generate spider silks and studied how to create microwires facile from commercial glue which is mainly composed of PVP. Micro-wire is very useful in a variety of engineering field and sensor applications, because of the structural characteristics. However, former techniques have some limitations such as controllability, high cost, and straightness.
From the facile and biomimetic methods, we fabricated the micro-wire and nano-material mixed micro-wire. The micro-wire we made have a strong mechanical stiffness (~50 GPa) and solubility to the various solvents. Particularly, ethanol molecules enable to control the diameter and mechanical stiffness of micro-wire. And also, when the nano-material (i.e., gold nanoparticle, zinc oxide nanowire, reduced graphene oxide), the mixed micro-wire has conductivity and some new characteristics according to mixed materials.
In this study, we focused on the reduced graphene oxide mixed micro-wire for detecting nitrogen dioxide gas molecules in the smart vehicle air. The nitrogen dioxide gas is included in vehicle exhaust and causes some toxicities. The reduced graphene oxide mixed micro-wire has a drastic change of conductivity according to binding of nitrogen dioxide molecules.