cm034185v_si_002.cif (32.99 kB)
Download fileThermoelectric Properties and Site-Selective Rb+/K+ Distribution in the K2-xRbxBi8Se13 Series
dataset
posted on 2003-06-25, 00:00 authored by Theodora Kyratsi, Duck-Young Chung, John R. Ireland, Carl R. Kannewurf, Mercouri G. Kanatzidisβ-K2Bi8Se13 possesses promising thermoelectric properties whereas Rb2Bi8Se13 does not.
The formation of solid solutions between these two compounds was attempted to study the
alkali metal distribution in the structure and its influence in the electronic properties. The
structure of the K2-xRbxBi8Se13 series of solid solutions was studied and the members with
0 < x ≤ 1 were found to adopt the β-K2Bi8Se13 structure. Detailed crystallographic studies
were performed for the x = 1.0 composition to examine in detail the K/Rb distribution in
the lattice and the effect on the K/Bi disorder that exists in the β-K2Bi8Se13 structure. The
Rb+ ions occupy exclusively one crystallographic site replacing K+. This defines RbKBi8Se13
as a new quaternary compound. Lattice parameters and band gaps are reported for the
different compositions. Charge transport measurements including electrical conductivity,
thermoelectric power, and Hall effect show that the materials are n-type semiconductors
with increasing carrier concentration as a function of composition x.