Highly sensitive single-walled carbon nanotube/polypyrrole/phenylalanine core–shell nanorods for ammonia gas sensing

Abstract

In this study, core–shell nanorod composites with a single-walled carbon nanotube (SWCNT) in the core and polypyrrole (PPy)/phenylalanine (PA) shells, SWCNT@PPy@PA, with an average diameter of 80 nm and length of 1–5 μm were successfully synthesized via a simple one-pot emulsion polymerization method. The obtained nanorod composites exhibited not only high conductivity but also high selectivity and sensitivity to ammonia gas. The SWCNT@PPy@PA core–shell nanorod-based sensors showed reliable detection at a concentration of 100 ppb even at room temperature and have the potential to be practically applied to gas sensors.