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

A novel 1D Co3O4/polyethyleneimine-carbon nanotubes composites (CoPCNTs) have been successfully synthesized via hydrothermal method at different temperature. The CNTs functionalized by polyethyleneimine (PCNTs) provided a new material with new structural and functional properties. The PCNTs was used as loading guider and electron transfer path. The Co3O4 nanoparticles (NPs) loaded on the PCNTs surface liked a snake winding around CNTs, and the size was about 5-10 nm. The gas sensing characteristics of the CoPCNTs sensors to carbon monoxide (CO) and ammonia (NH3) were evaluated with different gas concentration. The CoPCNTs sensors grown at 160 degrees C exhibited the highest response to CO and NH3 gases with response time of 4 s and 4.3 s at room temperature (RT), respectively. Hence, the approach developed in this work would be important for the low-cost and large-scale production of the CoPCNTs materials with highly promising applications in gas sensors. (C) 2015 Elsevier B. V. All rights reserved.