Laserprinten van Flexibele Thermoelektrische Materialen: Een weg naar schaalbare productie voor wearables en het Internet of Things

Thermoelectric (TE) technology enables the direct, solid-state conversion of thermal gradients into electrical power via the Seebeck effect, offering a maintenance-free and silent energy solution for low-power applications. While TE devices typically exhibit lower thermodynamic efficiencies compared to conventional vapor-compression cycles, their high reliability and scalability make them ideal for the emerging Internet of Things (IoT) and wearables ecosystem. With billions of distributed sensor nodes and wearable medical devices requiring sub-milliwatt power, harvesting waste heat from industrial infrastructure or metabolic heat from the human body presents a sustainable alternative to the ecological and logistical burdens of battery dependency. However, the widespread adoption of TEGs is currently bottlenecked by traditional 'top-down' fabrication. Conventional manufacturing, involving ingot synthesis, wafer dicing, and manual pick-and-place assembly, produces rigid, expensive modules non conformable to curved surfaces. This thesis addresses these challenges by developing Laser Powder Bed Fusion as a digital, 'bottom-up' manufacturing platform for the fabrication of flexible thermoelectric generators directly onto polyimide substrates. The research first establishes a robust processing framework for p-type Bi0.5Sb1.5Te3. Given the high-dimensional and non-linear parameter space of laser-matter interaction, a Support Vector Regression Machine Learning model was implemented to optimize the power factor. This data-driven approach successfully decoupled the competing effects of laser energy density and stoichiometric preservation, yielding materials with a power factor of ~1300 μW m-1 K-2, matching the performance of benchmark materials produced via traditional metallurgical routes. Extending beyond material synthesis, the work demonstrates fully integrated, planar flexible modules. These devices incorporate both n-type and p-type printed legs and were engineered to overcome parasitic electrical contact resistances. The resulting modules exhibited significant mechanical resilience, maintaining performance over 500 bending cycles. In practical energy harvesting scenarios, the devices generated ~ 30 µW from a household hot water pipe. Furthermore, the modules demonstrated active cooling of ~ 3 K within seconds, providing a versatile platform for local thermal management. Collectively, these results establish laser-printed thermoelectrics as a scalable, high-performance solution for powering the next generation of autonomous, conformal, and battery-free electronic systems.