Enhanced thermoelectric properties of poly(3,4‐ethylenedioxythiophene): Poly(styrenesulfonate)/copper phthalocyanine disulfonic acid composite films

Abstract A series of poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonate)/copper phthalocyanine disulfonic acid (PEDOT: PSS/CuPc‐[SO3H]2) composite films were prepared by using CuPc‐(SO3H)2 as the dopant. EG treatment was applied to further improve the thermoelectric properties of PEDOT: PSS/CuPc‐(SO3H)2 composites. Structural analyses indicated the strong π − π interactions existed between PEDOT: PSS and CuPc‐(SO3H)2, and led to more ordered regions in the composite films, and benefit the conductivity. CuPc‐(SO3H)2 can greatly improve the thermoelectric properties of PEDOT: PSS/CuPc‐(SO3H)2 composite films, which have a Seebeck coefficient of 13.2 μV K−1 and a conductivity of 2.8 × 105 S/m with 20 wt% CuPc‐(SO3H)2 at room temperature, and the corresponding power factor is 48.8 μW m−1 K−2, which is almost 6.83 times higher than the PEDOT: PSS films without CuPc‐(SO3H)2.