| Abstract Scope |
Thermal switches, which electrically control heat flow in a manner similar to how semiconductor field-effect transistors control drain current, have attracted significant attention for their potential to enable efficient thermal management in applications such as thermal displays.
However, previous thermal transistors contained liquid electrolytes, posing challenges for practical applications. Recently, we developed solid-state electrochemical thermal transistors using SrCoOx[1], LaNiO3[2], and CeO2[3] as active materials, with YSZ as the solid electrolyte. Especially, CeO2-based devices exhibit a high thermal conductivity (κ) of 12.5 W/mK in on-state and a low κ of 2.2 W/mK in off-state, achieving an on/off κ ratio of 5.8 and a κ-switching width of 10.3 W/mK over 100 cycles. This marks a significant step toward practical applications such as thermal displays.
[1] Q. Yang et al., Adv. Funct. Mater. 2023.
[2] Z. Bian et al., Adv. Sci. 2024.
[3] A. Jeong, M. Yoshimura et al., Science Adv. 2025. |