Thermogalvanic organohydrogel-based non-contact self-powered electronics for advancing smart agriculture

Non-contact sensors avoid physical contact with the external environment, ensuring long-term reliability and offering a broad spectrum of sensing applications. However, the requirement for an external power supply, poor mechanical properties, low output performance, and high costs limits their application. Herein, non-contact self-powered electronics are proposed based on a thermoelectric organohydrogel prepared using a rapid freeze–thaw method where Cu/Cu2+ serves as a redox couple in the binary solvent of DMSO/water. The organohydrogel exhibits favorable mechanical, anti-freezing, and anti-drying properties and maintains stable thermoelectric performance at temperatures ranging from 253 K to 333 K. By assembling with PDMS/CuO/Cu electrodes, the gel generates a maximum temperature difference of approximately 14.8 K and produces an open-circuit voltage of 15.2 mV under one sun via photothermal conversion. Successful applications of non-contact self-powered electronics based on photo-thermal-electric (PTE) conversion include remote-controlled small electronics, wireless information interaction, and solar intensity monitoring in greenhouses. In the long run, this work has the potential to achieve efficient management and intelligent control of agricultural production, presenting vast application prospects in the field of smart agriculture.