Thermoelectric properties of layered antiferromagnetic CuCrSe2

Here we study thermoelectric and magnetic properties of CuCrSe2 samples sintered at various temperatures. Structural analysis with XRD shows an order-disorder transition for Cr atoms when the sintering temperature is increased above 1273 K. Metal-like electrical resistivity and anomalously large Seebeck coefficient are found about room temperature. Analysis of electrical conductivity and Seebeck coefficient of the partially-disordered phase suggests hopping conduction of charge carriers. For both the ordered and disordered phases magnetic susceptibility follows Curie-Weiss temperature dependence at high temperatures above 150 K and shows an antiferromagnetic transition around 55 K. For the disordered phase, the effective magnetic moment is determined at 3.62 μB; this low value in comparison to the spin only value for Cr3+ of 3.89 μB indicates spin fluctuations in the paramagnetic state. The thermal conductivity in these phases is low and dominated by the lattice contribution. Values for the thermoelectric figure of merit (ZT) at room temperature are estimated to be 0.17 and 0.05 for the ordered and disordered phases, respectively.