One way for thermoelectric performance enhancement of group IIIB monochalcogenides

Exploring the thermoelectric materials of high performance is one way to satisfy the drastic energy demand and overcome the environmental issue. "Phonon-glass electron-crystal" might be a final target for searching the thermoelectric materials. In this paper, we present one mechanism to approach "phonon-glass electron-crystal": if we make the arrangement of the nuclei with the elements of the same group as the original atoms in the wellknown good thermoelectric materials as disorderly as possible, the lattice thermal conductivity could be drastically decreased, keeping their high thermoelectric power. We set group IIIB monochalcogenides as an example for confirming the above presentation. We show that substituting the atoms of the same family for some of the atoms does not affect the thermoelectric power too much by theoretically investigating the thermoelectric properties for the possible 20 systems composed of boron, aluminium, gallium, indium, selenium and tellurium. We think it necessary to investigate whether this mechanism is applicable to other thermoelectric materials or not. This might be helpful for researchers to design "phonon-glass electron-crystal".