Thermoelectric material with improved in figure of merit and method of producing same

1. A nanocomposite comprising:

a thermoelectric material nanoplatelet having a ratio of a largest diameter to a thickness of about 33 to about 125; and

a metal nanoparticle disposed on a surface of the thermoelectric material nanoplatelet, wherein the metal nanoparticle comprises a metal selected from Pt, Pd, and Au.

2. The nanocomposite of claim 1 , wherein the thermoelectric material nanoplatelet has a chemical formula of Bi 2 Te 3-x Se x wherein 0≦x≦3.

3. The nanocomposite of claim 2 , wherein the thermoelectric material nanoplatelet is selected from Bi 2 Te 3 , Bi 2 Se 3 , and a combination of Bi 2 Te 3 and Bi 2 Se 3 .

4. The nanocomposite of claim 2 , wherein the nanoplatelet has a thickness of about 4 to about 6 nanometers and a largest diameter of about 200 to about 500 nanometers.

5. The nanocomposite of claim 2 , consisting of the thermoelectric material nanoplatelet and the metal nanoparticle.

6. The nanocomposite of claim 1 , wherein the metal nanoparticle is present in an amount of about 0.1 to about 10 parts by weight, based on 100 parts by weight of the thermoelectric material nanoplatelet.

7. The nanocomposite of claim 1 , wherein the metal nanoparticle has a particle diameter of less than or equal to about 50 nanometers.

8. A bulk thermoelectric material comprising the nanocomposite of claim 1 .

9. The thermoelectric material of claim 8 , wherein the thermoelectric material comprises a metal nanoparticle disposed on a surface of the thermoelectric material nanoplatelet after treatment with spark plasma sintering.