Figures.

Polyaniline (PANI) and PANI-MnO2 composites were synthesized via a chemical route with varying manganese dioxide (MnO2) content, specifically 5wt% and 15wt%. X-ray diffraction (XRD) confirmed the structural formation of both PANI and PANI-MnO2 composites. The direct current conductivity was measured, showing an increase with temperature: at 393K, pure PANI had a conductivity of 2.25 × 10-4 S/cm, which increased significantly in the composites, reaching 9.03 × 10-4 S/cm for the 15wt% MnO2 composite. The Seebeck coefficient also increased with temperature and MnO2 concentration, achieving a maximum value of 52 mV K-1 at 373K for the 15wt% MnO2 composite. These results indicate that the synthesized PANI- MnO2 composites exhibit semiconducting behavior with improved thermoelectric properties, making them promising candidates for applications in thermoelectric devices such as generators and thermopiles. The study highlights the potential of these materials in enhancing the efficiency of thermoelectric energy conversion.