Organic solvent-based thermo-electrochemical cells with an iron(ii/iii) triflate redox couple for use in harvesting low-grade waste heat at 100–200 °C

Abstract

The need to harvest low-grade waste heat at 100–200 °C has attracted much attention. In this paper, the performance of thermo-electrochemical cells (TECs) with an iron triflate (Fe(CF₃SO₃)₂/Fe(CF₃SO₃)₃) redox couple is investigated in various organic solvents at temperatures exceeding 100 °C. The TECs in dimethylformamide (DMF) showed the maximum Seebeck coefficient of 1.51 mV K⁻¹, and the maximum power density of 660 mW m⁻¹ was achieved using 0.5 M iron triflate in DMF at ΔT = 120 K (145 °C on the hot-side).