Characterization of commercial thermoelectric organic composite thin films

A series traditional thermoelectric films, including n-type Bi, Bi₂Te₃, and p-type Sb, Sb₂Te₃, were synthesized with CH₃NH₃I by combining magnetron sputtering and thermal evaporation method. It is found that the Seebeck coefficients for all the composite films have enhanced although the electrical conductivities reduced due to the decreased carrier concentration. This leads to an obvious improvement of the power factor, especially for p-type Sb₂Te₃-based organic–inorganic hybrid films. As expected, a maximum power factor value around 2.3 mWm⁻¹K⁻² has been achieved for the composition of Sb₂Te₃/CH₃NH₃I in range of the whole measured temperature, which is nearly seven times higher than that of pristine Sb₂Te₃ film. By combination with the reduced thermal conductivity, a ZT value nearly 1.0 has been obtained at 380 K for the composition of Sb₂Te₃/CH₃NH₃I.