A smart sponge with pressure–temperature dual-mode sensing for packaging and transportation

Conventional sponges are limited to providing mechanical protection and lack the capability to monitor the real-time status of transported object. Consequently, there is an urgent need to develop smart sponges that can simultaneously protect and monitor the status of objects during transportation. In this study, we have developed a poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) melamine sponge (PEDOT:PSS@MS) using a dip coating-centrifugation method. The PEDOT:PSS@MS functions as a dual-mode sensor for pressure and temperature. The sensor has a maximum linear pressure sensitivity of 0.411 kPa⁻¹ within 42.7 kPa, and a fast recovery time of 46 ms. On the other hand, the sensor exhibits a linear temperature sensitivity of 9.42 μV/K via the Seebeck effect in the range of 30 to 80 °C. By integrating multiple PEDOT:PSS@MS units into a 3D-printed packing box, the pressure and temperature orientation distribution of the transported objects can be monitored in real-time. The development of these smart sponges enhances multimodal sensors for linear response performance, holding great potential in intelligent logistics security and advanced packaging solutions.