Presentation Information
[22p-C501-6]Absence of High On-to-Off Thermal Conductivity Ratio in the LaxSr1−xCoOy-based Thermal Transistors
〇(D)Zhiping Bian1, Mitsuki Yoshimura1, Ahrong Jeong2, Hiromichi Ohta2 (1.IST-Hokudai, 2.RIES-Hokudai2)
Keywords:
Thermal transistors,On-to-Off Thermal Conductivity Ratio
Thermal transistors that electrochemically switch the thermal conductivity (κ) of an active material have attracted growing attention as a device that controls heat flow. Recently, we realized the first solid-state thermal transistors using SrCoOx(2≤x≤3) as the active material and YSZ as the solid electrolyte. The on-to-off κ ratio was ~4, comparable to that of liquid electrolyte-based thermal transistors ever reported. We then clarified the way to improve the on-to-off κ ratio through an investigation of SrCo1−xFexOy solid solutions. We found that electron κ of SrCoO3 significantly contributes to the high κ, whereas the lattice κ of SrCoO2 is extremely low due to its defect structure. Consequently, SrCoOx (2≤x≤3) shows a rather large on-to-off κ ratio.
Very recently, Zhang et al. reported that La0.5Sr0.5CoOx (2.5≤x≤3) exhibits very high on-to-off κ ratio of ~5.4. Thus, La0.5Sr0.5CoO3 is promising for the active layer material of solid-state thermal transistors.
In order to clarify the overall trend of the κ and σ of LaxSr1−xCoOy solid solutions, we fabricated several thermal transistors using LaxSr1−xCoOy (0≤x≤0.6) solid solutions as the active layers and measured the κ and σ at room temperature.
Very recently, Zhang et al. reported that La0.5Sr0.5CoOx (2.5≤x≤3) exhibits very high on-to-off κ ratio of ~5.4. Thus, La0.5Sr0.5CoO3 is promising for the active layer material of solid-state thermal transistors.
In order to clarify the overall trend of the κ and σ of LaxSr1−xCoOy solid solutions, we fabricated several thermal transistors using LaxSr1−xCoOy (0≤x≤0.6) solid solutions as the active layers and measured the κ and σ at room temperature.