Thermoelectric properties of unoxidized graphene/Bi2Te2.7Se0.3 composites synthesized by exfoliation/re-assembly method

초록

Nanocomposites of n-type thermoelectric Bi2Te2.7Se0.3 (BTS) and unoxidized graphene (UG) were prepared from the exfoliated BTS and UG nanoplatelets. Polycrystalline BTS ingots were exfoliated into nanoscoll-type crystals by chemical exfoliation, and were re-assembled with UG nanoplatelets. The composites were chemically reduced by hydrazine hydrate and sintered by a spark-plasma-sintering method. The thermoelectric properties of the sintered composites were evaluated and exhibited decreased carrier concentration and increased thermal conductivity due to the embedded graphene. The peak ZT values for the UG/BTS-US and UG/BTS-EX composites were approximate to 0.8 at the UG concentration of 0.05 wt%. ((c) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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