Synthesis and H₂S sensing performance of MoO₃/Fe₂(MoO₄)₃ yolk/shell nanostructures

H₂S gas, even in a low concentration in the environment, is very harmful to the health of human beings. Thus, the design and fabrication of gas sensors for detecting trace H₂S gas are highly desirable. Herein we developed a facile method to fabricate MoO₃/Fe₂(MoO₄)₃ yolk/shell nanostructures with porous features. As the yolk/shell nanostructures were used to fabricate H₂S gas sensors, they exhibited high sensor response, relatively rapid recovery and response times, and good selectivity and long-term stability. The sensor response value of MoO₃/Fe₂(MoO₄)₃ yolk/shell nanostructures to 1 ppm H₂S gas was up to 1.7 even at a low working temperature (70 °C), significantly higher than those of MoO₃ nanorods and other types of MoO₃ based nanocomposites. Our results demonstrate that the yolk/shell nanostructures have very promising applications in high-performance H₂S sensors.