Facile Fabrication of Hybrid Carbon Nanotube Sensors by Laser Direct Transfer.

Ammonia is one of the most frequently produced chemicals in the world, and thus, reliable measurements of different NH concentrations are critical for a variety of industries, among which are the agricultural and healthcare sectors. The currently available technologies for the detection of NH provide accurate identification; however, they are limited by size, portability, and fabrication cost. Therefore, in this work, we report the laser-induced forward transfer (LIFT) of single-walled carbon nanotubes (SWCNTs) decorated with tin oxide nanoparticles (SnO NPs), which act as sensitive materials in chemiresistive NH sensors. We demonstrate that the LIFT-fabricated sensors can detect NH at room temperature and have a response time of 13 s (for 25 ppm NH). In addition, the laser-fabricated sensors are fully reversible when exposed to multiple cycles of NH and have an excellent theoretical limit of detection of 24 ppt.