Synergistic Enhancement of Ionic Thermoelectric Properties in Cementitious Composites via Dual-Mechanism Coupling for Building Energy Harvesting

Driven by the global energy transition and carbon neutrality goals, cement-based ionic thermoelectrics─as a “structure–function integrated” power generation technology─are driving a significant advancement in the building and energy sectors. This study establishes a dual-mechanism framework for thermoelectric phenomena in cementitious composites, involving both thermally driven ion migration (Soret effect) and redox-potential-driven thermogalvanic coupling. Under thermal gradient, the [Fe(CN)6]3–/[Fe(CN)6]4– redox couple and cations in cement exhibit enhanced diffusion, ultimately yielding cementitious materials with superior thermoelectric properties. Notably, a Seebeck coefficient of 11.25 mV·K–1 and a power factor of 17.2 μW·m–1·K–2 have been achieved. These results provide innovative insights for the diversified functional development of cementitious composites and offer a perspective on energy conversion functionalization in building materials.