Room temperature detection of low-concentration H2S based on CuO functionalized ZnFe2O4 porous spheres

Room temperature H 2 S gas sensor with low detection limit is necessary for practical application. In this work, ZnFe 2 O 4 was synthesized through a simple solvothermal method, and then CuO was decorated onto the surface of ZnFe 2 O 4 via a modified metal organic framework synthesis method. After a series of characterization methods, it was found that CuO/ZnFe 2 O 4 had porous nanosphere morphology. Gas sensing measurements indicating that the synthesized CuO/ZnFe 2 O 4 porous spheres exhibited excellent H 2 S sensing performance under room temperature, including high sensitivity under low concentration (less than 10 ppm), excellent selectivity, low limit of detection (0.1 ppm), good repeatability, and fast response/recovery time. The sensing mechanism was discussed in detail, which is mainly contributed to the sensitization effect of CuO. This work provides a new strategy for constructing room temperature H 2 S gas sensor based on ZnFe 2 O 4 . • Porous CuO/ZnFe 2 O 4 nanospheres were successfully synthesized via a simple two-step solvothermal method. • The porous CuO/ZnFe 2 O 4 nanospheres exhibited excellent H 2 S gas sensing property at room temperature. • The porous CuO/ZnFe 2 O 4 nanospheres possess a low detection limit of 0.1 ppm. • The improved gas sensing performance of ZnFe 2 O 4 was mainly due to the sensitizing effect of CuO.