Fabrication of PbTe porous thermoelectric materials by KCl-mixing

A novel sintering process has been developed for porous thermoelectric devi ces such as gas-combustion-type and heat-exchange-type devices. Mixture of PbTe and KCl particles with a certain particle diameter and volume fraction of KCl was sintered at 973 K, 7.2 ks. 35 MPa. The KCl particles were remov ed by water and porous PbTe was obtained. Porosity ratio, specific surface area and permeability of gas were controlled by changing volume fraction of KCl and diameter of PbTe particles. Addition of KCl during sintering did n ot affect the Seebeck coefficient of PbTe. Therefore, this process can be a pplied to production of porous PbTe thermoelectric devices.