Selective, sensitive, and reversible detection of H2S using Mo-doped ZnO nanowire network sensors

Abstract

Mo-doped ZnO nanowire (NW) networks were prepared by coating the MoS₂ layer through successive ionic layer adsorption and reaction and subsequent heat treatment at 600 °C for 2 h. The resulting Mo-doped ZnO NW network sensor demonstrated a high gas response of 14.11 to 5 ppm H₂S at 300 °C, which is 7.66–11.47 times higher than those of 5 ppm C₂H₅OH, NH₃, HCHO, CO, H₂, o-xylene, benzene, toluene, and trimethylamine. The reversibility of the sensor signal, as well as the response and selectivity to H₂S, is significantly improved by Mo doping into the ZnO NW networks, which can open various applications to monitor H₂S in an indoor atmosphere, industrial petroleum/gas, and automobile exhaust gas.