Lewis-Acid Mediated Hierarchical Ce/P-WO₃ Microbeggarticks-Nanoneedles for High-Efficiency Listeria Monocytogenes...

Listeria monocytogenes, a common foodborne pathogen, poses significant risks to public health. The 3-hydroxy-2-butanone (3H-2B) produced during its metabolism serves as a biomarker for indirectly assessing microbial contamination in foods. Existing semiconductor gas sensors for 3H-2B often struggle to balance high stability and sensitivity due to the trade-off between the number of active sites and the stability of the sensing materials. This study synthesized polyoxomethoxide-derived Ce modified P-WO₃ hierarchical microbeggarticks nanoneedles by using a novel cluster-nuclei assembly strategy, where Ce doping synergistically amplifies Lewis acidity is enabled by W-O_v-Ce ternary active sites, which stabilize the W⁵⁺/W⁶⁺ mixed valence states, enhancing 3H-2B chemisorption and material durability. The 3H-2B micro-electromechanical system (MEMS) sensor exhibits both reliable repeatability and exceptional long-term stability over 30 weeks. The underlying mechanism is elucidated using in situ Fourier transform infrared spectroscopy and on-line mass spectrometry. Furthermore, the sensor exhibited high selectivity and sensitivity for detecting Listeria monocytogenes. Density functional theory calculations indicated that Ce⁴⁺ embedded in the P-WO₃ lattice resulted in higher adsorption energy for 3H-2B. Furthermore, the device integrates a wireless sensor module enabling remote, real-time detection of L. monocytogenes, providing an effective solution for global quality assessment of salmon during cold chain transportation.