Enhancement of thermoelectric power factor by modulation doping of bulk polycrystalline SnS / thin film PEDOT:PSS bilayer

Modulation doping occurs in a heterojunction where charge carrier-rich material transfers to carrier-deficient material. The modulation-doped is intentionally selected have higher carrier mobility than the modulation dopant material, so that overall electrical conductivity can be boosted. Although this strategy has proven effective enhancing power factor thermoelectrics, selection criteria for such semiconductor couples not been explicitly clarified, resulting only few discovered available doping-driven thermoelectric systems [1-4]. Here, we (i) report an electronic band structure-based guideline actualize doping, (ii) reveal hole-rich PEDOT:PSS dope otherwise undoped tin monosulfide (SnS) their bilayered structure, (iii) prove responsible enhancement by comparing computational and experimental Seebeck coefficient values. optimized thin film / SnS pellet structure had 134.7 fold improvement 93.6 over those of SnS, with ~ 20 % decrease coefficient. effect result further when becomes nanoscale or nanoparticles future.