The effect of 3d-electron configuration entropy on the temperature coefficient of redox potential in Co1−zMnz Prussian blue analogues

Abstract

Recently, it was reported that a thermocell can convert temperature into electrical energy by using the difference in the thermal coefficient (α ≡ dV/dT) of the redox potential (V) between the cathode and anode materials. Here, we systematically investigated α of Na_xCo_1−zMn_z[Fe(CN)₆]_y (Co_1−zMn_z-PBA) against Mn concentration (z). The z-dependence of α is interpreted in terms of the 3d-electron configuration entropy (ΔS_3d) of the redox site. Utilization of S_3d is a strategy effective for the design of high-|α| materials for energy harvesting thermocells.