Enhanced and selective ammonia sensing behaviour of poly(aniline co-pyrrole) nanospheres chemically oxidative polymerized at low temperature

• Polyaniline (PAN), polypyrrole (PPY) and their copolymer, poly(ani co-py) PAP, nanostructures based sensors were synthesized.
• The fabricated sensors from these polymers can detect low level of ammonia as low as 10 ppm at room temperature.
• Copolymer based sensor (PAP) showed enhanced and selective sensing response towards ammonia as compared to its parent homopolymer sensors (PAN & PPY).
• PAP sensor is found to be reliable in terms of response, recovery, reproducibility and reversibility.

Poly(aniline co-pyrrole) (PAP), polyaniline (PAN) and polypyrrole (PPY) nanostructures were fabricated by template less chemical oxidative polymerization of aniline and pyrrole at low temperature and evaluated as chemiresistive ammonia sensor. The structural analysis was done by Fourier transform infrared spectroscopy (FTIR), which confirms the formation of respective polymers whereas, field effect scanning electron microscopy (FE-SEM) revealed the formation of PAP nanospeheres with diameter around 100 nm, PAN nanofibres with diameter around 50 nm and PPY nanospheres with diameter around 500 nm. It is observed that PAP sensors showed excellent sensing towards low concentration (10 ppm) of ammonia, as compared to its homopolymers based sensors at room temperature. PAP sensor was found to be reliable in terms of low cost, recovery time, selectivity, reproducibility, detection range and stability.