Temperature Sensor Fabricated via Direct Laser Writing on Copper Nanoparticles Coated Paper Substrates

Abstract

Measuring temperature is crucial, as it affects biological, chemical, and physical processes, impacting climate control, healthcare, and industrial operations. This work introduces a novel flexible and fully printed temperature sensor, based on copper nanoparticle electrodes direct laser written and coated with a screen-printed film of Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on a paper substrate. The sensor shows a linear response with a sensitivity of -0.15%/°C in the 30-50°C temperature range. Hysteresis evaluation at different humidity levels (30% RH, 50% RH, and 80% RH) reveals the lowest average hysteresis at 50% RH, indicating the most stable and reliable performance at these conditions. Our sensor platform combines the advantages of biocompatible nanomaterials and paper substrates, offering a scalable and ecofriendly solution for temperature sensing, potentially applicable in plant wearable scenarios in precision agriculture.