ChemInform Abstract: Synthesis, Crystal Structure and Thermoelectric Properties of a New Carbide Zr₂[Al_3.56Si_0.44]C₅.

Abstract

0.44 ]C 5 . -The title compound is synthesized from a pressed pellet of a mixture of ZrC, Al, SiC, and graphite embedded in Al4C3 powder (vacuum,1973 K, 1 h followed by sintering at about 40 MPa, 1973 K, 5 min) and characterized by powder XRD, TEM, and thermopower and electrical conductivity measurements. The compound crystallizes in the trigonal space group R3m with Z = 3. The structure is composed of electroconductive NaCl-type ZrC slabs separated by [Al 3.56 Si 0.44 ]C 3 layers. The thermoelectric properties of the title material are superior to those of Zr2Al3C4 and Zr3Al3C5, with the power factor reaching 7.6·10 -5 Wm -1 K -2 . -(FUKUDA*, K.; HISAMURA, M.; IWATA, T.; TERA, N.; SATO, K.; J. Solid State