Hsu, Ching ChiehChing ChiehHsuLin, Yen-TingYen-TingLinHong, Shao HuanShao HuanHongJeng, U. SerU. SerJengChen, Hsin LungHsin LungChenJIASHING YUCHENG-LIANG LIU2024-04-092024-04-092024-01-012366-74862366-7486https://scholars.lib.ntu.edu.tw/handle/123456789/641814The present study focuses on the utilization of a hydrogel consisting of gelatin methacrylate (GelMA) and polyvinyl alcohol (PVA) as a matrix for hosting the redox couple Fe(CN)63−/4−. The hydrogel exhibits a discernable thermopower (Src) of 3 mV K−1. The beneficial effect of the hydrogel microstructure on the mechanical robustness is demonstrated by small-angle X-ray scattering (SAXS). Moreover, the hydrogel is used to construct a 3D printed thermoelectric generator (TEG) consisting of eight p-type thermoelectric legs, which exhibits commendable thermoelectric properties, including an open-circuit voltage of 64 mV and a power density of 4.0 mW m−2 under a temperature gradient (ΔT) of 2.5 K. These findings demonstrate that 3D printing both enhances the quality of the interface between the hydrogel and electrode and provides a promising method for a more facile TEG fabrication process with the potential for further applications in low-grade waste heat harvesting.3D printing | hydrogel | microstructure | SAXS | thermo-electrochemical cellsjournal article10.1002/adsu.2024000392-s2.0-85188083524https://api.elsevier.com/content/abstract/scopus_id/85188083524