ABSTRACT

An improvement in the thermoelectric properties of calcium cobaltite ceramics (Ca₃Co₄O₉) was demonstrated through a modified co-precipitation method and lanthanum doping. With highly reactive precursors derived from the modified method, the energy consumption was conserved due to an apparent decrease in calcination duration. The conventional sintering produced a layer structure with the interconnected grains and the pores, which simultaneously optimised the thermal and electrical conductivity. The thermoelectric property was improved by the combination of the special morphology and ion substitution. The figure of merit ZT reached 0.205 (600°C) which was a competitive value for polycrystalline Ca₃Co₄O₉ ceramics. The study provided a potential route for scalable production of Ca₃Co₄O₉ ceramics with low energy use and excellent performance.

摘要

通过改进的共沉淀法和镧掺杂证明了钴酸钙陶瓷（Ca ₃ Co ₄ O ₉）的热电性能的改善。使用衍生自改良方法的高反应性前体，由于煅烧时间明显缩短，因此可以节省能量。常规烧结产生具有相互连接的晶粒和孔的层结构，这同时优化了热导率和电导率。通过特殊的形貌和离子取代相结合提高了热电性能。ZT的品质因数达到0.205（600°C），是多晶Ca ₃ Co ₄ O的竞争价值₉陶瓷。该研究为低能耗和优异性能的Ca ₃ Co ₄ O ₉陶瓷的规模化生产提供了一条可能的途径。