Traditional thermoelectric (TE) building materials are limited in both performance and durability, requiring enhancements for effective energy solutions. This research investigates strain‐hardening geopolymeric composites (SHGC) for TE sensing applications. The influence of metal oxides on mechanical strength and TE characteristics is evaluated using isothermal calorimetry, computed tomography scanning, and focused ion beam (FIB)–transmission electron microscopy analysis. At ambient temperature, SHGC samples with MnO₂ exhibit the highest Seebeck coefficient of 5470 μV K⁻¹ with a measured power density of 29 μW m⁻². Despite the presence of small strain cracks, the SHGC maintains about 69% of its original ZT value even after long‐term use. This discovery underlines the durability and efficiency of SHGC, demonstrating their potential for future infrastructure applications. The cost‐effectiveness, temperature‐sensing abilities, and environmental advantages of SHGC make them well suited for large‐scale smart applications.
