ZnO-SnO2 nanocomposites modified by PdO nanoparticles named PdO-ZSO as gas sensing material for hydrogen and butane with the excellent response time and recovery time

This paper reports the synthesis of ZnO-SnO2 nanocomposites modified by PdO nanoparticles named PdO-ZSO which are prepared by the one-step hydrothermal method at 160 °C for 12 h and gas sensing test to H2 and C4H10 inflammable gas. Meanwhile, PdO-ZSO nanoparticles are XRD, SEM, TEM, EDS, XPS and other characterization methods to further explain its morphological formation process. As the sensing materials, PdO-ZSO exhibits extraordinary gas sensing behaviors for hydrogen (H2) and butane (C4H10) and the response reaches 98 and 58 to H2 and C4H10 at operating temperature of 370 °C, respectively. And the response time and recovery time are both less than 2 s and 4 s respectively, with good repeatability and outstanding long-term stability. The existence of PdO is able to increase the resistance modulation range of heterostructure. And the enhanced gas sensing performances can be ascribed to the catalysis of noble metal doping and the formation of ternary heterostructure between PdO and ZnO-SnO2 nanocomposites.