Adsorption sensitivity of Ag-decorated carbon nanotubes toward gas-phase compounds

The authors reported the gas-phase CO2 and NH3 adsorption characteristics of Ag-decorated carbon nanotubes (CNTs). High-density CNTs were grown on an oxidized Si substrate by thermal chemical vapor deposition. The average length and diameter of the CNTs were approximately 4.52 μm and 45 nm, respectively. Ag nanoparticles were coated onto the nanotube surfaces to a thickness of approximately 7 nm. The Ag-coated CNTs were sensitive to CO2 and NH3 vapors and could be used to provide a sensor for these gases. The Ag-decorated samples showed stable, reproducible responses and good recovery.