PET Functional Upcycling through Surface-Assisted Growth of Ni-BDC MOFs and Laser-Induced Carbonization towards Bend Resistive Sensor

The growing accumulation of waste polyethylene terephthalate (PET) presents a significant environmental challenge requiring the development of sustainable recycling methods. In this study, we propose a novel approach for upcycling PET waste into bend resistive sensors through laser-assisted carbonization of surface-grown Ni-BDC (BDC = 1,4-benzenedicarboxylate). The fabrication process involves the solvothermal formation of a homogeneous Ni-BDC layer, followed by treatment with a 405 nm laser system to create a graphene-like layer with enhanced conductivity (sheet resistance 6.2 ± 3.4 Ω per square). The developed sensor demonstrates remarkable robustness, a linear response in a wide bending angle range (6 to 44º), as well as excellent mechanical stability and stiffness. This contribution paves the way for the development of cost-effective and eco-friendly devices based on low-cost polymer waste as a resource for applications in the Internet of Things.