Flower-like WO₃ Nanorod Structures Modified\nwith MoS₂ Quantum Dots for Low-Temperature Acetone Detection

Abstract

As a prevalent volatile organic compound (VOC), acetone\nplays a\nsignificant role in diverse domains, such as environmental protection,\nindustrial production, and medical diagnosis. However, if acetone\nis not adequately monitored and disposed of, it can result in immeasurable\nadverse effects on human health and the natural environment. Therefore,\nit is essential to realize the highly sensitive, convenient, and efficient\nreal-time detection of acetone. In this study, MoS₂ quantum\ndots (QDs) were modified on flower-like WO₃ nanorod structure\nthrough the hydrothermal approach to fabricate a WO₃/MoS₂ sensor. The sensing performance of the sensor for acetone\nwas investigated. The results showed that the sensor had a response\nvalue of 14.96 for 30 ppm of acetone gas at optimum operating temperature\n(132 °C), which was 3.2 times the performance of a pure WO₃ gas sensor. The response of the WO₃/MoS₂ sensor was reduced by only 20% under a relative humidity of 85%.\nBesides, the sensor still maintained a high response (11.25 for 30\nppm) under high curvature conditions (120°). Finally, the sensitization\neffects of MoS₂ QDs, including the formation of n-n heterojunction\nwith WO₃ and the catalytic overflow of oxygen species,\nwere discussed in detail. This study provides a valuable reference\nfor the construction of low-temperature and high-performance gas sensors\nbased on QD-sensitized metal oxide nanomaterials.