Thermoelectric devices with polymer/zeolite hybrid composite films for conversion of heat to electricity

Here we report that organic/inorganic hybrid composite films, consisting of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and zeolite Y (Zy), can efficiently convert heat to electricity in the horizontal device geometry. The PEDOT:PSS/Zy (PPZy) hybrid composite films were prepared from corresponding aqueous solutions at various Zy contents (up to 50 wt%). The PPZy solutions exhibited an increased viscous state with a maximum at Zy = 30 wt%, indicating strong interactions between PEDOT:PSS and Zy components. All devices with the PPZy composite films could convert heat to electricity and showed higher thermoelectric (TE) performances than those with the pristine PEDOT:PSS films. The TE devices with the PPZy films (Zy = 30 wt%) delivered an output power of 8.8 pW with a power factor of 0.76 μW/mK², which is ca. 20 times higher than those with the pristine PEDOT:PSS films. The flexible TE devices, which were fabricated on poly(ethylene naphthalate) (PEN) film substrates, exhibited robust TE performances even after 5000 bending cycles. The present approach of hybrid composite films based on zeolite particles may contribute to further TE performance improvement for flexible and wearable TE devices.