Thermoelectric Properties of n-type Poly (nickel 1,1,2,2-ethenetetrathiolate) Prepared by a New One-step Solvothermal Method

Abstract

Poly(nickel 1,1,2,2-ethenetetrathiolate) (poly[Na _x(Ni-ett)]) is one of the most promising n-type organic thermoelectric materials which can be used in wearable devices. However, the conventional solution method is time-consuming and the prepared poly[Na _x(Ni-ett)] usually has poor crystallinity, which does not benefit for achieving high thermoelectric performance. Here, a new one-step solvothermal method under the high reaction temperature and high vapor pressure was developed to prepare poly[Na _x(Ni-ett)] with a quite short period. The experimental results show crystallinity and electrical conductivity are greatly enhanced as compared with those prepared by conventional solution method. As a result, a maximum ZT value of 0.04 was achieved at 440 K, which is about four times of the polymer prepared by the conventional solution method. This study may provide a new route to enhance the TE properties of n-type organic thermoelectric materials.

Keywords

thermoelectric / organic materials / n-type poly[Na _x(Ni-ett) / solvothermal method

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