Wearable NO2 sensing and wireless application based on ZnS nanoparticles/nitrogen-doped reduced graphene oxide

Wearable electronics consists of mechanically flexible sensor networks and the corresponding circuit system can provide real-time monitoring and recording of toxic gases. In this work, we present a convenient watch-type wearable nitrogen dioxide (NO2) sensor based on ZnS nanoparticles/nitrogen-doped reduced graphene oxide (ZnS NPs/N-rGO) as a flexible device. The power consumption of the flexible sensor is as low as 0.52 mu W. The response value of the device for 10 ppm NO2 is 2.2; while the recovery time is 724 s, with a low theoretical limit of detection at 69 ppb, with the device maintaining stable mechanical durability. By reading and analyzing the signal data through wireless bluetooth transmission, the device can provide timely monitoring and early warning for NO2 leakage. Furthermore, the impressive room-temperature sensing performance of ZnS NPs/N-rGO is attributed to factors of geometrical and electronic effects. More specifically, ZnS NP uniformly dispersed on rGO greatly expands the effective contact area with the target gas molecules, and the built-in electric field formed by the strong charge interaction between them also effectively improves the detection sensitivity. The successful development of this type of wireless wearable sensor provides an effective reference for the future application and development of high-performance, low-power, and lightweight sensing equipment.

Automated summary

This study presents a convenient watch-type wearable NO2 sensor with low power consumption and stable mechanical durability, allowing for real-time monitoring and early warning of toxic gases through wireless bluetooth transmission. The impressive sensing performance of ZnS NPs/N-rGO is attributed to geometrical and electronic effects, which is significant for the future development of low-power, high-performance sensing equipment.