An in situ “detector/conductor” strategy to construct hollow MoO3/MoO2 nanoreactor for aniline detection

Abstract It is still a challenge to develop sensing materials towards rapidly and sensitively detecting aniline at 5 ppm. Herein, an in situ “detector/conductor” strategy is reported to design of double-layered MoO3/MoO2 nanoreactors for superior aniline detection. Hollow MoO2 microspheres were prepared and subsequently applied to produce MoO3/MoO2 via an in situ oxidation procedure. The dynamic transformation was monitored by operando XRD device. Metallic MoO2 substrates act as the “conductor” to improve the electroconductivity, and the semiconductive MoO3 play the role of the “detector” to sense the toxic gas. As a result, the response of the optimized MoO3/MoO2-3 sensor was 14.7 to 5 ppm aniline at 200 °C, and the recover and recover time were only 16 and 21 s. The response was much higher than other results reported by far. Density functional theory results revealed that the band structures and adsorption energies of MoO3 to aniline molecules can be modulated via introducing MoO2.