Organic/Inorganic n-type PVDF/Cu0.6Ni0.4 hybrid composites for thermoelectric application: A thermoelectric generator made of 8 pairs of p-leg ZnSb/Sb and n-leg β-PVDF/Cu0.6Ni0.4

Organic polymers have attracted attention because of their low thermal conductivity, low cost, ease processing, low processing temperature, and flexibility. A series of beta-PVDF/Cu0.6Ni0.4 composites was fabricated. Conductive atomic force microscopy (C-AFM) indicates that the conductive path is significantly increased with increasing content of Cu0.6Ni0.4 in the composite. The thermal conductivity of Cu0.6Ni0.4 is significantly reduced by compositing with beta-PVDF. The highest zT = 0.14 is attained at 400 K for the composite with the weight ratio of PVDF/Cu0.6Ni0.4 = 1/6 having the electrical conductivity of 760.5 S/cm, Seebeek coefficient of -49.9 mu V/K, and thermal conductivity of 0.53 W/m-K at 400 K. A thermoelectric generator (TEG) consisting of 8 pairs of p-leg ZnSb/Sb and n-leg beta-PVDF/Cu0.6Ni0.4 was fabricated. The maximum power output of 456.44 nW is attained with the output voltage of 9.35 mV and output current of 155.833 mu A at Delta T = 27 K. The maximum power density is 766.376 mu W/cm(2) at Delta T = 27 K. This work provides an effective way for making a thermoelectric generator by hybridizing n-type organic polymers containing PVDF with inorganic thermoelectric alloys at a relatively low temperature.

Automated summary

Organic polymers have attracted attention due to their low cost, ease of processing, flexibility, and low thermal conductivity. By hybridizing PVDF with Cu0.6Ni0.4, a composite material with significantly increased conductive path and reduced thermal conductivity has been fabricated. The composite material with a specific weight ratio achieves a high zT value at 400 K. Additionally, the fabricated thermoelectric generator exhibits high power output and power density at ΔT = 27 K.