Reduced graphene oxide (rGO) decorated TiO2 microspheres for selective room-temperature gas sensors

Reduced graphene oxide (rGO) decorated TiO 2 microspheres are prepared by using the hydrothermal method . The as-synthesized sample shows that TiO 2 particles are connected by the rGO nanosheets while some TiO 2 particles are found to be partly covered by rGO sheets. The rGO-decorated TiO 2 based chemoresistive-type sensor shows good sensitivity and excellent selectivity to different concentrations of ammonia from 5   ppm to 50   ppm at room temperature . However, the response and recovery speeds of the sensor to ammonia are sluggish and need further optimization.