The development of autonomous or self-powered IoT sensors represents a key challenge and energy harvesting technologies are attractive to convert mechanical, thermal, radiofrequency, solar, magnetic or fluid flow energy into electrical energy. A next-generation of functional materials and low cost devices with a better balance between environmental footprints, materials / processing costs and technical performances is required for a large-scale deployment of energy harvesters. In this context, IMTNE & IMTA are involved for several years into PhD Position – Fabrication of 3D antennas for radio-frequency energy harvesting various research projects (for example, BIOHARV & THERMOHARV INTERREG projects & GENEPI ANR project, OPAL, SAFIRS) dealing with sustainable vibrational and thermal gradients energy harvesters.
Following these initiatives, a collaboration between IMT NE and IMTA has been initiated to develop radiofrequency harvesters based on three-dimensional (3D) shaped rectennas. However, the limitations of current technologies hinder the development of 3D antennas that offer higher gain and improved omnidirectionality compared to flat antennas. To address this challenge, the project proposes an innovative combination of additive manufacturing and screen printing. A shape-memory polymer substrate will be printed in a flattened form, screen-printed with conductive inks, and then redeployed to regain its initial 3D shape. The objective is to produce high-performance, cost-effective devices with complex geometries. Preliminary studies have demonstrated the feasibility of this concept, yielding promising results while also highlighting areas for improvement, such as dimensional control, ink adhesion, and 3D device performance.
