Irrigation-friendly sensor to manage drought in crops through carbon-based signature volatile sensing

Water scarcity is a global challenge in agriculture, which is growing unprecedentedly. Hence, a metal oxide decorated graphene oxide (GO) particles coated interdigitated chemo-resistive volatile sensor has been developed here to sense beta-caryophyllene, an important signature terpene molecule released by the plant during water stress. The interface between the ZnO and GO composite has been found to show outstanding complementary behavior, through selective permittivity and optimum working temperature, which cause oxidization at multiple sites that take the sensitivity to -27 ppb concentration. The sensor has been validated in the crop that experiences water stress equivalent to 3 wet units in the soil moisture tensiometer, which is the critical value to irrigate the crop.