Effect of Nitrogen Atoms in the CNT Structure on the Gas Sensing Properties of PANI/CNT Composite

Herein we report the gas-sensitive properties to ammonia (at 2–10 ppm) of individual nanostructures a polyaniline/nitrogen-doped carbon nanotube composite with nitrogen content 0 at.% (uCNTs), 2 (N-CNTs) and 4 (N+-CNTs). Doping nanotubes was carried out in order both reduce electron work function, form potential barrier at “PANI-CNTs” interface, contribution conductivity. An increase CNTs leads an conductivity, decrease formation defects outer walls CNTs. It found that structural chemical state polymer layer all composites is same. However, morphology on changes dramatically increasing CNTs: thin smooth uCNTs, globular N-CNTs, thick sheet-like structure N+-CNTs. All showed same response time (~20 s) recovery (~120 s). Ammonia sensitivity 10.5 ± 0.2, 15.3 0.5 2.2 0.1 ppm−1 for PANI/uCNTs, PANI/N-CNTs PANI/N+-CNTs, respectively. Based results obtained here, came conclusion morphological features different have dominant effect gas reaction than change electronic interface “PANI-CNT”.