High-performance carbon nanotube hydrogen sensor

A hydrogen sensor of high sensitivity and selectivity based on the composite of single-walled carbon nanotube (SWCNT) and chitosan was developed. The intrinsically limited response of SWCNT to hydrogen is greatly improved with the assistance of the conjugate material in the composite, or in the chitosan. Furthermore, the chitosan surrounding the SWCNTs selectively passes through the hydrogen molecules, filtering out other polar molecules, enhancing the selectivity of the SWCNT sensor towards hydrogen. The improvements are achieved with the amino and hydroxyl functional groups of chitosan in contact with the SWCNTs.