Fabrication and thermoelectric power of π-shaped Ca_3Co_4O_9/CaMnO_3 modules for renewable energy conversion

摘要

The thermoelectric modules of it-shaped 1-, 2-, and 4-pairs are constructed using p-type Ca_(2.76)Cu_(0.24) Co_4O_9 and n-type Ca_(0.8)Dy_(0.2)MnO_3 oxide materials. The reacted phases at the interfaces of the Ca_(2.76)Cu_(0.24)Co_4O_9/Ag electrode and Ca_(0.8)Dy_(0.2)MnO_3/Ag electrode are not observed. The output powers of the fabricated it-shaped modules are measured, depending on the operating parameters and number of thermoelectric module pairs. The output powers of single thermoelectric modules increase with an increase in temperature difference AT between the hot- and cold-side temperatures of the modules, i.e., 2.42, 3.65, 4.26, 5.70, 7.13, and 8.42 mW for AT = 250, 269, 293. 305, 324, and 346 ℃, respectively. The maximum output powers of 1-, 2-, and 4-pair thermoelectric modules are roughly proportional to the number of p-n pairs. Oxide-based thermoelectric devices can be considered useful tools for green energy generation.