Enhanced thermoelectric properties of flexible Cu2−xSe (x ≥ 0.25) NW/polyvinylidene fluoride composite films fabricated via simple mechanical pressing. Issue 3 (5th January 2017) - Pammi, S. V. N.
Abstract : Enhanced thermoelectric properties of flexible Cu2− x Se NW-PVDF composite films fabricated via vacuum filtration followed by mechanical pressing (VFMP) has been studied. Abstract : We report the fabrication of Cu2− x Se NW-polyvinylidene fluoride (PVDF) composite flexible thin films using various approaches such as simple drop casting (DC), vacuum filtration (VF), and vacuum filtration followed by mechanical pressing (VFMP). The highest power factor of Cu2− x Se NW-PVDF composite films reached 105.32 μW m −1 K −2 when mechanical pressing was performed following vacuum filtration at 303 K, and this was further enhanced to 253.49 μW m −1 K −2 at 393 K. Cu2− x Se NW-PVDF composite films fabricated via vacuum filtration without mechanical pressing showed a reasonable power factor (<40 μW m −1 K −2 at room temperature), whereas films fabricated via the drop casting method showed a poor power factor (<10μW m −1 K −2 at room temperature). VFMP-treated Cu2− x Se NW-PVDF thermoelectric films showed good mechanical durability until 1000 bending cycles without significant performance degradation. When all these results are considered, the fabricated composite films could be a feasible option for p-type thermoelectric materials in thermoelectric power generators.