Flexible and Shape‐Morphing Plant Sensors Designed for Microenvironment Temperature Monitoring of Irregular Surfaces

Abstract

Flexible plant sensors play a critical role in smart agriculture due to their advantages in real‐time monitoring physiological signals of plants, and are experiencing growth in recent years. Such devices are expected to be directly placed on surfaces of plant organs for better detection. However, most existing sensors based on the planar substrate are not able to adapt to nondevelopable surfaces of plants, and are unsatisfactory in biocompatibility. Herein, considering the complexity of the plant surface, flexible temperature sensors for leaves and fruits are developed. The leaf temperature sensor is based on the porous substrate, which is designed to minimize its effect on plant respiration, and is demonstrated to measure temperature changes accurately after long‐time integration with a leaf. By mechanical design, the fruit temperature sensor realizes the transformation from a planar shape to a tridimensional shape, and is demonstrated to work on a variety of complex curved surfaces without loss of performance. The proposed shape‐morphing structure expands the capabilities of current planar electronics, and links thin‐film technology to spatial deformable devices. Results of the in vitro experiments show that these two proposed sensors hold promise to monitor microenvironment temperature in plant biology.

Tailoring the supramolecular interaction of ionic liquids for high-sensitivity temperature monitoring under high pressure

“…1e, the sensitivity increases with the higher concentration of iron ions, and the sensitivity also significantly improves with temperature elevation. The ionic liquid containing 400 mg mL −1 FeCl 3 exhibits an impressive sensitivity of up to 30.65%/°C, surpassing the reported values of traditional temperature-sensitive materials 16–36 (Fig. 1f) and much higher than that of PT100 (0.278%/°C), which is commonly used for high-precision temperature monitoring.…”

“…1 Therefore, developing temperature sensors with high precision and environmental adaptability remains a signicant challenge. A variety of inorganic and organic temperature-sensitive conductive materials have been developed for resistive temperature sensors, including metals (gold, 16 silver, 17 and chromium 18 ), MXenes, 19 carbon materials (carbon nanotubes, 20 graphene, 21,23 graphite, 22 and carbon black nanoparticles 24 ), conductive polymers, 25,26 ionic hydrogels, [27][28][29][30] ionogels, [31][32][33][34][35] ionic liquids, 36 and commercial PT100. Among these materials, ionic liquids exhibit excellent potential for temperatureresponsive applications.…”

Advanced biosensing technologies for monitoring of agriculture pests and diseases: A review

“…Wearable biosensors, developed to assess the status of plant health, have been exploited to measure the physiological and biochemical variations continuously by profiling relevant trait and microclimate parameters. The nanomaterialsbased biosensors feature high flexibility and excellent mechanical strength, improving accessibility of miniaturized and portable devices in the fields of wearable bioelectronic devices, which might meet the demands for on-site monitoring and early detection [43,56] . For example, flexible, stretchable and wearable carbon nanotube/graphite sensors were worn on the fruits of Solanum melongena and Cucurbita pepo, connecting with a readout circuit to make the real-time measurement of plant growth.…”

A Roadmap from Functional Materials to Plant Health Monitoring (PHM)

“…Furthermore, biometric measurements, such as transpiration and respiration, can be used to determine how well a plant communicates with its surroundings and how much moisture it retains. [ 121,122 ]…”