Hybrid Fe2O3/CNT Thin Films for Gas Sensor Applications

Thin films of Fe nanoparticles (NPs)/CNT networks were synthesized through vertical floating catalyst chemical vapor deposition technique (FC-CVD) and collected directly onto a cellulose membrane filter. Fe NPs/CNT films were transferred onto glass (or Si) substrates simply by dissolving filters, and then annealed in air at a low temperature for 8 hrs to create Fe
₂
O
₃
NPs. The effect of annealing temperature ranging from 150 to 550°C on the morphology and structures of the Fe
₂
O
₃
/CNTs films was investigated by field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Fe
₂
O
₃
/CNTs film-based sensors were tested against LPG gas under room temperature. LPG sensing-performance (sensor response and response/recovery time) of the Fe
₂
O
₃
/CNTs films-based sensor varied depending on the annealing temperature. The results of this study reinforce the potential of hybrid Fe
₂
O
₃
/CNTs films as a sensing material for LPG detection at low operating temperature.