Controllable synthesis of Co3O4/polyethyleneimine-carbon nanotubes nanocomposites for CO and NH3 gas sensing at room temperature

Co3O4/polyethyleneimine-carbon nanotubes composites (CoPCNTs) have been successfully controllable synthesized via hydrothermal method at different temperature. The CoPCNTs sensors exhibited the highest response to CO and NH3 gases with response time of 4 s and 4.3 s, low detection limit of 5 ppm and 1 ppm at room temperature, respectively. The enhanced gas sensing could be ascribed to the synergistic effect between the tiny size of Co3O4 and good conductivity of carbon nanotubes functionalized by polyethyleneimine.143