Cellulose–titanium dioxide–multiwalled carbon nanotube hybrid nanocomposite and its ammonia gas sensing properties at room temperature

A titanium dioxide (TiO2)–multiwall carbon nanotube (MWCNT) nanocomposite was synthesized by hydrothermal process. X-ray diffractometry, transmittance electron microscopy observation revealed that the nanocomposite has high nanocrystal structure. After blended with cellulose, a cellulose–TiO2–MWCNT hybrid nanocomposite was made and applied to a room temperature ammonia (NH3) gas sensor. The cellulose–TiO2–MWCNT hybrid nanocomposite exhibited much higher response and faster recovery for NH3 gas when the gas concentration changed from 50 ppm to 500 ppm. The gas sensing mechanism of the hybrid nanocomposite gas sensor is also discussed. This hybrid gas sensor is flexible and cheap with good sensitivity and repeatability.