Highly sensitive 3-hydroxy-2-butanone gas sensor based on p-Cr2O3/n-SnO2 binary heterojunction nanofibers

Listeria monocytogenes (LM) in food can release the 3-hydroxy-2-butanone (3H-2B) biomarker. Herein, a new proposal is presented to develop a highly sensitive 3H-2B gas sensor for the real-time monitoring of LM. This sensor is based on p-Cr2O3/n-SnO2 binary heterojunction nanofibers, which are obtained via a controllable process including electrospinning and calcination. The maximum response of as-built sensors to 5 ppm 3H-2B reaches 50 at 240?, and the detection limit can be as low as 20 ppb. Moreover, the Cr2O3/SnO(2 )sensor also exhibits a short response/recovery time (9 s/4 s), remarkable selectivity, and superb long-term stability. The excellent 3H-2B sensing performance is mainly ascribed to the p-n heterojunctions between Cr2O3 and SnO2 in nanofibers, providing a promising route to design high-efficient 3H-2B gas sensors for food safety.

Automated summary

A new proposal for developing a highly sensitive 3H-2B gas sensor for real-time monitoring of Listeria monocytogenes (LM) in food is presented. The sensor, based on p-Cr2O3/n-SnO2 binary heterojunction nanofibers, shows excellent 3H-2B sensing performance with high selectivity and stability.