Mingyue Zhou, Bolong Xu, Dong Wang, Zhaofeng Wu, Lu Zhang, Sheng Cai
Acetone, a key biomarker for metabolic processes, and its excessive levels can cause ketosis or even ketoacidosis, posing significant risks to human health. Therefore, real-time acetone detection is crucial for noninvasive health monitoring. Ti 3 C 2 T x -based sensors demonstrated considerable potential for detecting VOC gases but often face issues with sensitivity and environmental stability. In this work, a flower-like Ti 3 C 2 T x anchored with MoS 2 quantum dots (F–Ti 3 C 2 T x /MoS 2 ) was proposed for the first time to achieve accurate acetone detection even under high humidity conditions. The unique flower-like morphology significantly increased the surface area of Ti 3 C 2 T x and amplified its electron scattering effects. MoS 2 modification not only reduced the content of Ti defects but also formed a passivation layer, providing a novel approach to address the inherent oxidation issue of Ti 3 C 2 T x . Moreover, the p–n heterojunction between F–Ti 3 C 2 T x and MoS 2 promoted charge separation, enabling high-performance acetone detection. Compared with intrinsic Ti 3 C 2 T x, a 4.83-fold enhancement in response to 25 ppm of acetone was achieved by using a F–Ti 3 C 2 T x /MoS 2 sensor with an ultralow detection limit of 163.2 ppb and a rapid response/recovery time (26.0 s/33.7 s). When integrated into a portable breath analyzer, the sensor demonstrated accurate acetone monitoring under atmospheric conditions, underscoring its potential for real-time and noninvasive health diagnostics.