Room-Temperature High-Performance H2S Sensor Based on Porous CuO Nanosheets Prepared by Hydrothermal Method

Porous CuO nanosheets were prepared on alumina tubes using a facile hydrothermal method, and their morphology, microstructure and gas sensing properties were investigated.The monoclinic CuO nanosheets had an average thickness of 62.5 nm and were embedded with numerous holes with diameters ranging 5 nm to 17 nm.The porous CuO nanosheets were used to fabricate gas sensors to detect hydrogen sulfide (H 2 S) operated at room temperature.The sensor showed a good response sensitivity of 1.25 with the respond/recovery time of 234 s and 76 s, respectively, when tested with the H 2 S concentrations as low as 10 ppb.It also showed a remarkably high selectivity to the H 2 S, but only minor responses to other gases such as SO 2 , NO, NO 2 , H 2 , CO and C 2 H 5 OH.The working principle of the porous CuO nanosheets based sensor to detect the H 2 S was identified to be the phase transition from semiconducting CuO to a metallic conducting CuS.