Photothermoelectric (PTE) characterization of CuCrO2 and Cu4Sn7S16 thermoelectric materials

Abstract

The recently developed photothermoelectric (PTE) calorimetry was applied to measure the thermal parameters of CuCrO2 and Cu4Sn7S16 thermoelectric materials. Both back and front PTE detection configurations were combined to directly measure the thermal diffusivity and effusivity of the above-mentioned solid thermoelectrics. In the back configuration, CuCrO2 (Seebeck coefficient approximately + 1200 µV K−1) was used as a thermoelectric sensor and CuCrO2 and Cu4Sn7S16 as samples. In the front detection, both CuCrO2 and Cu4Sn7S16 (Seebeck coefficient approximately − 600 µV K−1) materials were alternatively used as sensors, the sample being in this case a thermally thick layer of silicone grease. The proposed combination of configurations eliminates any possible results degeneracy because each fitting procedure involves only one fitting parameter. The results obtained by PTE investigations α CuCrO2 = 1.19 × 10−6 m2 s−1, α Cu4Sn7S16 = 0.33 × 10−6 m2 s−1 and e CuCrO2 = 780 W s1/2 m−2 K−1, e Cu4Sn7S16 = 1358 W s1/2 m−2 K−1 were validated by photopyroelectric (PPE) measurements.