Abstract
Ammonia is a well-known toxic and colorless gas that is widely produced in various chemical and biological industries; thus, developing high-performance gas sensors for the detection of NH(3) is essential. Herein, we prepared a high-performance NH(3) gas sensor based on SnO(2) nanowires coated with Pt by the sputtering method and studied the effect of Pt coating on the gas-sensing performance. Single-crystal SnO(2) nanowires were grown by the CVD method, and sputtering was used to control the thickness of the Pt coating layer. We demonstrated that the NH(3) gas-sensing performance of Pt-SnO(2) nanowires was significantly enhanced compared to that of pristine SnO(2) nanowires. The 5 nm Pt-SnO(2) nanowire sensor exhibits a high response (R (a)/R (g)) of 19.98 toward 500 ppm NH(3) gas, which is a 19-fold enhancement compared with that of the bare SnO(2) nanowires. The sensor exhibited a fast response and recovery with excellent selectivity over the interfering species C(2)H(4), H(2), and acetone. We also proposed a mechanism for the enhanced sensitivity of Pt-SnO(2) nanowires toward NH(3).