Fermi Level Dependence of a Working Electrode on the Open Circuit Voltage in a Sensitized Thermal Cell

Power Generation at Room Temperature

“…The VOC value is caused by the difference between the redox potential of the electrolyte ions and the Fermi level of the working electrode. 10 Comparing the discharge capacities of the 1st 200 nA discharge, that of Cell-342 was the smallest, thereby indicating that the sustainability of the power generation was influenced by ion convection inside the electrolyte.…”

“…We recently reported a sensitized thermal cell (STC) that is a new thermal energy conversion system [6][7][8][9][10][11] , which was inspired by the concept of a dye-sensitized thermal cell (DSSC). [12][13][14][15][16] Utilising STCs, electric power can be generated "directly" from heat via the redox reactions of electrolyte ions with thermally excited carriers in semiconductors (Fig.…”

“…In principle, VOC of STC is independent of the temperature and is the difference between the Fermi level of the working electrode and the redox level of the electrolyte ions. 10 Regarding Ge/(Cu ions in polyethylene glycol (PEG)) STC in this work, VOC was ~0.35 V. Assuming that the theoretical short-circuit current value was the number of reactive ions reaching the electrode interface per second, it would be estimated as ~60 and for the Ge/(Cu ion in PEG) STC combshaped electrode (5 m) based on the saturation concentration of the electrolyte, the ion mobility 24 and electric field that were applied to the electrolyte (SI 7). This indicated that the output powers were 0.2 and 40 mW/cm 2 at RT and 60 °C, respectively, which are comparable to that of solar cells (6 mW/cm 2 ) and are sufficient to employ STCs in IoT devices (sensor: W~, wireless power transmission: mW~) 25 .…”

Power Generation at Room Temperature -How to Design of the Sensitized Thermal Cell-

“…We recently reported a sensitized thermal cell (STC) that is a new thermal energy conversion system [6][7][8][9][10][11] , which was inspired by the concept of a dye-sensitized thermal cell (DSSC). [12][13][14][15][16] Utilising STCs, electric power can be generated "directly" from heat via the redox reactions of electrolyte ions with thermally excited carriers in semiconductors (Fig.…”

“…In principle, V OC of STC is independent of the temperature and is the difference between the Fermi level of the working electrode and the redox level of the electrolyte ions. 10 Regarding Ge/(Cu ions in polyethylene glycol (PEG)) STC in this work, V OC was ~0.35 V. Assuming that the theoretical short-circuit current value was the number of reactive ions reaching the electrode interface per second, it would be estimated as ~60 and 150 microA/cm 2 at RT and 80 °C, respectively, for the Ge/(Cu ion in PEG) STC comb-shaped electrode (5 micro m) based on the saturation concentration of the electrolyte, the ion mobility 21 and electric eld that were applied to the electrolyte (SI 7). This indicated that the output powers were 0.2 and 40 mW/cm 2 at RT and 60 °C, respectively, which are comparable to that of solar cells (6 mW/cm 2 ) and are su cient to employ STCs in IoT devices (sensor: micro W~, wireless power transmission: mW~) 22 .…”