Quantum Dots‐Engineered Flexible Hydrogel as Plant‐Wearable Sensor for on‐Site Profiling Dynamic Pesticide Degradation

Abstract Engineering wearable devices for in situ and on‐site monitoring of pesticide residues from plants in a non‐destructive manner is of great research value but remains a huge challenge. In this study, a plant‐wearable fluorescence sensor CdTe CDs@PVA@AG, is designed and constructed by embedding CdTe QDs in polyvinyl alcohol (PVA) and agarose (AG)‐co‐assembled double‐network hydrogel to transmit on‐the‐scene pesticides residues messages. Harnessing red emission and stimuli‐responsive performance of CdTe QDs, as well as hydrogel's excellent flexibility, high adhesion, and porous network, CdTe CDs@PVA@AG is endowed with quantitative response to thiram at ≈µ m level within 2 min through promoting fluorescence silence in conjunction with the transformation of images into primary colors as digital signals. More interestingly, CdTe CDs@PVA@AG is capable of being tightly pasted onto various crops’ surfaces and then is not only explored to appraise pesticide residue levels but also to profile the dynamic pesticide degradation, in a non‐destructive manner. This work opens up a new avenue to engineer plant‐wearable devices for in situ, on‐site, and non‐destructive capturing of the pesticide residue information from crops, favoring the accurate monitoring of the health status of crops, and rapid and healthy development of smart agriculture.