Selective detection of trace carbon monoxide at room temperature based on CuO nanosheets exposed to (111) crystal facets

In recent years, carbon monoxide (CO) intoxication incidents occur frequently, and the sensitive detection of CO is particularly significant. At present, most reported carbon monoxide (CO) sensors meet the disadvantage of high working temperature. It is always a challenge to realize the sensitive detection of carbon monoxide at room temperature. In this study, CuO nanosheets exposed more (111) active crystal facets and oxygen vacancy defects were synthesized by a simple and environmentally friendly one-step hydrothermal method. The sensor has good comprehensive gas sensing performance, compared with other sensors that can detect CO at room temperature. The response value to 100 ppm CO at room temperature is as high as 39.6. In addition, it also has excellent selectivity, low detection limit (100 ppb), good reproducibility, moisture resistance and long-term stability (60 days). This excellent gas sensing performance is attributed to the special structural characteristics of 2D materials and the synergistic effect of more active crystal facets exposed on the crystal surface and oxygen vacancy defects. Therefore, it is expected to become a promising sensitive material for rapid and accurate detection of trace CO gas under low energy consumption, reduce the risk of poisoning, and then effectively protect human life safety.

Automated summary

Carbon monoxide (CO) intoxication incidents have been occurring frequently in recent years, highlighting the importance of sensitive CO detection. Most currently reported CO sensors have the disadvantage of requiring high working temperatures, making it a challenge to achieve sensitive detection at room temperature. In this study, CuO nanosheets with exposed active crystal facets and oxygen vacancy defects were successfully synthesized using a simple and environmentally friendly hydrothermal method. The sensor exhibited excellent comprehensive gas sensing performance, surpassing other sensors in detecting CO at room temperature. The response value to 100 ppm CO at room temperature reached as high as 39.6. Additionally, the sensor demonstrated excellent selectivity, low detection limit (100 ppb), good reproducibility, moisture resistance, and long-term stability (60 days). These outstanding gas sensing capabilities can be attributed to the unique structural characteristics of the 2D materials and the synergistic effect of the exposed active crystal facets and oxygen vacancy defects. Therefore, this sensor is expected to become a promising sensitive material for rapid and accurate detection of trace CO gas with low energy consumption, reducing the risk of poisoning and effectively protecting human life safety.