P1GS.8 - UV assisted NH3 Gas Sensor based on Ternary Reduced Graphene Oxide/TiO2/Au composites at Room Temperature

17th International Meeting on Chemical Sensors - IMCS 2018
2018-07-15 - 2018-07-19
Vienna, Austria
P-1 - Gas Sensors
Y. Zhou, C. Gao, Y. Guo - Key Laboratory of Optoelectronic Technology and System of Ministry of Education, College of Optoelectronic Engineering, Chongqing University, Chongqing (China)
535 - 535


Ammonia gas is a hazardous gas species, which will impose great threat on human health and ecological environment. Thus, it is of great importance to selectively and sensitively detect NH3 gas at low level. In this report, we adopt hydrothermal method to prepare tenary composites of reduced graphene oxide nanosheets (rGO), TiO2 nanotubes and Au nanoparticles, and then probe NH3 gas spanning from 1 ppm to 10 ppm under UV illumination (365 nm) at room temperature (25 oC). Within the composites, rGO nanosheets serve as a template to provide attachment sites of TiO2 and Au, and supress their aggragation via the steric hindrance effect. TiO2 nanotubes as a typical UV light-sensitive material contribute a mass of photogenerated electron-hole pairs, which will well react with exposed NH3 molecules. Meanwhile, incorporation of Au nanoparticles could significantly increase the sorption sites due to the spillover effect. As expected, the as-prepared sensors enable a room-temperature detection response of 10% toward 1 ppm NH3 under UV illumination as well as an excellent selectivity, repeatability and long-term stability, which is far incapable for other prepared ones based on random binary composites or individual component. In brief, the ternary sensors have exhibited huge superiority in trace-level NH3 detection in terms of low-power consumption and high sensitivity.