Advantages

- By dispersing insulating graphene oxide within the coating electrode material through a novel approach, the electromotive force of liquid thermoelectric devices increased by an order of magnitude compared to conventional methods.
- Temperature differences between electrodes generate an electromotive force due to changes in the ambient temperature.

Background and Technology

　Liquid thermoelectric devices are devices that convert environmental heat into electricity. The researcher had been generating a large thermoelectric voltage using a large-area, low-cost liquid thermoelectric device with a coated electrode containing dispersed graphite particles, but the thermoelectric voltage was only 30-40 mV at a temperature difference of 30 K.
　In this study, the researcher generated an electromotive force of approximately 300 mV with a temperature difference of 30 K between electrodes by dispersing insulating graphene oxide in the electrode material. Furthermore, this electromotive force persists even after electrode cooling (e.g., due to daytime heating persisting into nighttime).

Current Stage and Key Data

When a 30K temperature difference was applied between the electrodes, the open-circuit voltage (Voc) increased to 292mV (left figure). The maximum output reached 0.40W/m^2 (right figure).
*The area of the graphene oxide dispersion electrode is 42 mm^2, the electrode spacing is 10 mm, and the electrolyte is a 0.8 M aqueous solution of Fe(ClO₄)₂/Fe(ClO₄)₃.

Partnering Model

We are seeking companies interested in exploring patent licensing or joint research opportunities.

Principal Investigator

Yutaka MORITOMO
(University of Tsukuba, Institute of Pure and Applied Sciences, Professor）

Patents and Publications

- Patent pending
- The 86th JSAP (The Japan Society of Applied Physics) Autumn Meeting 2025 “Liquid thermoelectric converter with huge electromotive force” (Haruka Yamada et al.)