Radial ZnO nanorods decorating CoO nanoparticles for highly selective and sensitive detection of the 3-hydroxy-2-butanone biomarker

• Published in: Nanoscale 2022-01, Vol.14 (2), p.482-491
• Main Authors: Wang, Chen, Du, Lingling, Xing, Xiaxia, Feng, Dongliang, Tian, Yingying, Li, Zhenxu, Zhao, Xinhua, Yang, Dachi
• Format: Article
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/d1nr06729j

Indirect monitoring of Listeria monocytogenes (LM) via a gas sensor that can detect the bacterial metabolite 3-hydroxy-2-butanone (3H-2B) is a newly emerged strategy. However, such sensors are required simultaneously endow with outstanding selectivity, high sensitivity, and ppb-level detection limit, which remains technologically challenging. Herein, we have developed highly selective and sensitive 3H-2B sensors that consist of zinc oxide nanorods decorated with cobaltosic oxide nanoparticles (ZnO NRs/Co 3 O 4 NPs), which have been synthesized by combined optimized hydrothermal and annealing process. Specifically, the ZnO NRs/Co 3 O 4 NPs exhibit ultrahigh sensitivity to 5 ppm 3H-2B ( R a / R g = 550 at 260 °C). The sensor prototypes enable detection as low as 10 ppb 3H-2B, show excellent long-term stability, and present remarkable selectivity through interfering selectivity survey and principal component analysis (PCA). Such outstanding sensing performance is attributed to the modulated electron depletion layer by n-p heterojunctions and abundant gas diffusion pathways via the radial architecture, which was verified via electrochemical impedance spectroscopy test, Mott-Schottky measurement, and ultraviolet-visible absorption analysis. Our highly selective and sensitive ZnO NRs/Co 3 O 4 NPs have the potential in the real-time detection of 3H-2B biomarker. Radial-architecture ZnO nanorods/Co 3 O 4 nanoparticles have been developed for detecting 3-hydroxy-2-butanone biomarker, presenting ultrahigh response ( R a / R g = 550, 5 ppm), low detection limit (10 ppb), preeminent selectivity and outstanding stability.