CuCr_1−xMg_xO₂ (x = 0 and 0.02) epitaxial thin films were prepared on 5°/10° vicinal cut α-Al₂O₃ (000l) substrates using pulsed laser deposition. The laser-induced thermoelectric voltage (LITV) effect in these inclined delafossite thin films was observed for the first time. The thin films were characterized by resistivity temperature measurement and atomic force microscopy. Because of the enhanced resistivity anisotropy and high carrier concentration in the ab-plane owing to Mg doping, the 10°-tilted CuCr_0.98Mg_0.02O₂ film exhibits an evident LITV signal with a maximum transverse thermoelectric voltage of 156 mV. Thermal conductivity results indicate that CuCr_1−xMg_xO₂ (x = 0 and 0.02) films have a dominant phonon thermal conductivity, which may contribute to a long decay time for the LITV signal. These results indicate potential for future transverse thermoelectric applications based on transparent conductive oxides.

High-temperature thin film heat flux sensors have been fabricated by growing c-axis tilted epitaxial Ca3Co4O9 (CCO) thin films on 5° vicinal cut LaAlO3 (001) single crystal substrates. The layered structure of Ca3Co4O9 yields the significant Seebeck coefficient anisotropy between the ab-plane and c-axis, which could generate a voltage of the heat flux sensor via the transverse thermoelectric (TTE) effect of thin films. A sensitivity of 27.7 μV/(kW/m2) has been determined in such 5° tilted Ca3Co4O9 thin films, which is much larger than other reported ones based on the TTE effect from various materials. After a thermal treatment at 900 °C in air for 10 min, the sensitivity of such heat flux sensors is almost non-variable, which indicates that the temperature resistance of the CCO-based TTE heat flux sensor is as high as 900 °C. In addition, a fast response time of 45 μs has been identified in such CCO-based TTE heat flux sensors. These results demonstrate that the CCO is a promising candidate to manufacture the TTE heat flux sensors with the superiorly comprehensive performance, including the high temperature resistance, high sensitivity, and fast response.

Graphenylene has an unusually higher ZT at low temperature (0.5 at 300 K) than at high temperature (0.3 at 800 K) for n-type doping along the x-axis, contrary to the conventional view that higher ZT values exist in the high temperature range.