Unveiling the Remarkable Potential of Geopolymer-Based Materials by Harnessing Manganese Dioxide Incorporation

Thermoelectric (TE) building materials have the potential to revolutionize sustainable architecture by converting temperature differences into electrical energy. This study introduces geopolymeric TE materials enhanced with manganese dioxide (MnO₂) as a modifying agent. Calorimetric experiments examine the impact of MnO₂ on geopolymerization. Mechanical tests show that adding MnO₂ (up to 5% by weight) improves the geopolymer composite's strength, achieving a peak compressive strength of 36.8 MPa. The Seebeck effect of the MnO₂-modified geopolymeric composite is also studied. The inclusion of MnO₂ boosts the Seebeck coefficient of the geopolymer, reaching a notable 4273 µV C⁻¹ at a 5% MnO₂ dosage. This enhancement is attributed to an increase in the density of states (DOS) and a reduction in relaxation time. However, excessive MnO₂ or high alkali levels may adversely affect the Seebeck coefficient by lengthening the relaxation time.