Optimization of thermoelectric parameters in Ag/MnO₂ nanocomposite-based flexible thermoelectric generators

The fabrication of flexible thermoelectric generators (FTEGs) using MnO₂ and the screen-printing method represents a novel approach in the field of thermoelectric applications. MnO₂ and Ag/MnO₂ were utilized as key thermoelectric materials, fabricated using a scalable and cost-effective screen-printing technique. The incorporation of Ag as a composite with MnO₂ significantly enhanced the thermoelectric properties by modulating electrical resistivity, band gap, carrier concentration, and microstructural features such as crystallite size and porosity. Among the five fabricated MnO₂-based FTEGs, the 3 wt% Ag-composite MnO₂ sample demonstrated the highest power output of 292 nW at a temperature gradient (ΔT) of 100 °C, exceeding the power output of pure MnO₂ by a threefold margin. This improvement is attributed to the decoupling of thermal and electrical transport properties, resulting in ultra-low internal resistance and enhanced flexibility. The Ag/MnO₂ FTEGs exhibit superior thermoelectric performance and mechanical flexibility compared to conventional materials like PANI, PEDOT, Cu₂Se, and Bi₂Te₃, underscoring their potential for thermoelectric applications.