Advanced Glass Fiber Polymer Composite Laminate Operating as a Thermoelectric Generator: A Structural Device for Micropower Generation and Potential Large-Scale Thermal Energy Harvesting
George Karalis, Lazaros Tzounis, Kyriaki Tsirka, Christos K. Mytafides, Angelos Voudouris Itskaras, Marco Liebscher, Eleftherios Lambrou, Leonidas N. Gergidis, N.‐M. Barkoula, Alkiviadis S. Paipetis
Abstract
This study demonstrates for the first time a structural glass fiber-reinforced polymer (GFRP) composite laminate with efficient thermal energy harvesting properties as a thermoelectric generator (TEG). This TEG laminate was fabricated by stacking unidirectional glass fiber (GF) laminae coated with p- and n-type single-wall carbon nanotube (SWCNT) inks via a blade coating technique. According to their thermoelectric (TE) response, the p- and n-type GF-SWCNT fabrics exhibited Seebeck coefficients of +23 and −29 μV/K with 60 and 118 μW/m·K2 power factor values, respectively. The in-series p–n interconnection of the TE-enabled GF-SWCNT fabrics and their subsequent impregnation with epoxy resin effectively generated an electrical power output of 2.2 μW directly from a 16-ply GFRP TEG laminate exposed to a temperature difference (ΔT) of 100 K. Both experimental and modeling work validated the TE performance. The structural integrity of the multifunctional GFRP was tested by three-point bending coupled with online monitoring of the steady-state TE current (Isc) at a ΔΤ of 80 K. Isc was found to closely follow all transitions and discontinuities related to structural damage in the stress/strain curve, thus showing its potential to serve the functions of power generation and damage monitoring.