Metal organic framework sensors on flexible substrate for ammonia sensing application at room temperature

Abstract

The application of sensitive gas sensors manufactured in high volume at low cost is of great interest due to an extensive array of potential applications. Such areas include industrial processing, biotechnology and intelligent food packaging. This work reports a straightforward and versatile technique using screen-printing and drop-casting processes, to produce gas sensors on a flexible plastic substrate, based on a combination of metal organic framework and graphene-carbon materials. We demonstrate a sensitive and stable ammonia sensor (4.6% maximal response) over a range from 20 to 100 ppm. The sensitivity of the optimized formulation is 36 times higher than a carbon–graphene only sensor and makes the developed devices suitable for intelligent packaging. The sensor production process is fast, reliable and low-cost and so there is a strong potential for the process principles to be adapted industrially for a different gas target or application.