Alkaloid Precipitant Reaction Inspired Controllable Synthesis of Mesoporous Tungsten Oxide Spheres for Biomarker Sensing
Keyu Chen, Wenhe Xie, Yu Deng, Yu Deng, Jingting Han, Yongheng Zhu, Jianguo Sun, Kaiping Yuan, Limin Wu, Yonghui Deng, Yonghui Deng
Abstract
Highly porous sensitive materials with well-defined structures and morphologies are extremely desirable for developing high-performance chemiresistive gas sensors. Herein, inspired by the classical alkaloid precipitant reaction, a robust and reliable active mesoporous nitrogen polymer sphere-directed synthesis method was demonstrated for the controllable construction of heteroatom-doped mesoporous tungsten oxide spheres. In the typical synthesis, P-doped mesoporous WO 3 monodisperse spheres with radially oriented channels (P-mWO 3 -R) were obtained with a diameter of ∼180 nm, high specific surface area, and crystalline skeleton. The in situ-introduced P atoms could effectively adjust the coordination environment of W atoms (W δ+ -O v ), giving rise to dramatically enhanced active surface-adsorbed oxygen species and unusual metastable ε-WO 3 crystallites. The P-mWO 3 -R spheres were applied for the sensing of 3-hydroxy-2-butanone (3H2B), a biomarker of foodborne pathogenic bacteria Listeria monocytogenes ( LM ). The sensor exhibited high sensitivity ( R a / R g = 29 to 3 ppm), fast response dynamics (26/7 s), outstanding selectivity, and good long-term stability. Furthermore, the device was integrated into a wireless sensing module to realize remote real-time and precise detection of LM in practical applications, making it possible to evaluate food quality using gas sensors conveniently.