In this paper, we investigated the effect of single and multi-dopants on thermoelectrical properties of host ZnO films.
Incorporation of the single dopant Ga in the ZnO films improved the conductivity and mobility but lowered the Seebeck coefficient.
Dual Ga- and In-doped ZnO thin films show slightly decreased electrical conductivity but improved Seebeck coefficient.
The variation of thermoelectric properties is discussedin terms of film crystallinity, which is subjected to the dopants’ radius.
Small amounts of In dopants with a large radius may introduce localized regions in the host film, affecting the thermoelectric properties.
Consequently, a 1.5 times increase in power factor, three times reduction in thermal conductivity, and five-fold enhancement in the figure of merit ZT have been achieved at 110°C.
The results also indicate that the balanced control of both electron and lattice thermal conductivities through dopant selection are necessary to attain low total thermal conductivity.
Nhận xét
Đăng nhận xét