Enhanced sensitivity of Au@Bi2WO6 flower-like materials to formaldehyde

Bi₂WO₆ flower-like materials (FMs) were prepared by a hydrothermal method, followed by an in-situ reduction method to prepare Au@Bi₂WO₆ FMs. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy were employed to characterize the samples. It was discovered that the calculated O_V content of Au@Bi₂WO₆ FMs is 25.16% whereas that of Bi₂WO₆ FMs is 20.81%, offering appropriate active sites for the absorption of gases and thus enhancing outstanding sensing property. Moreover, the detection of volatile and hazardous substances such as formaldehyde, methanol, acetone, benzene, toluene, and xylene was carried out to assess the efficacy of the Au@Bi₂WO₆ FMs sensors. The optimal operating temperatures for the Bi₂WO₆ FMs and Au@Bi₂WO₆ FMs sensors were 290 and 260 °C, respectively. Compared with Au@Bi₂WO₆ FMs sensor and Bi₂WO₆ FMs one, the best response of the front was 250 (900)–100 (800) ppm formaldehyde whereas that of the latter was 90 (230). Therefore, Au@ Bi₂WO₆ FMs have good response and selectivity, which are promising candidates for formaldehyde detection.