講演情報
[22a-B203-4]Development of Cu2Se/Ag2(S,Se)-based monolithic thermoelectric generators for energy harvesting applications
〇Artoni Ang1, Itsuki Yamazaki1, Saurabh Singh2, Masaharu Matsunami1, Tsunehiro Takeuchi1 (1.Toyota Tech. Inst., 2.Inst. Sci. Tech. Austria)
キーワード：
Thermoelectric generator、Chalcogenides
Thermoelectric generators (TEGs) have recently emerged as an alternative energy source, particularly for small wireless sensors used in the internet-of-things (IoT). TEGs are able recover waste heat and directly covert it to useful electricity. Commercial TEGs designed for room temperature (RT) operation are composed of state-of-the-art p- and n-type Bi2Te3 based thermoelectric (TE) materials arranged in a π-type structure, where the TE legs are bridged by metal interconnects. However, these materials consist of toxic and rare elements, and the π-type structure requires a complicated and energy intensive fabrication process.
In this work, we develop an alternative TEG device architecture that can be fabricated using a simple and low energy cost method. Monolithic TEGs consist of thin p- and n- type layers stacked together with an insulating spacer partially separating them. Using Cu- and Ag- chalcogenides possessing excellent RT TE properties, we were able to assemble monolithic TEGs using a simple and low energy cost process by co-sintering stacks of p-type Cu2+xSe, insulating Ag2S, and n-type Ag2SxSe1-x at low temperatures.
Previously, our TEGs suffered from high contact resistances, limiting the maximum power output of the devices. Using finite element method (FEM) simulations, the TEG device structure was optimized to increase the device voltage and decrease the contact resistance.
Our new TEG design replaced the pn-junction with a metal interconnect as the electrical contact between the p- and n-type TE layers and increased the maximum power density from 0.27 mW/cm2 to 0.68 mW/cm2 at a ΔT=30K. This was achieved by a small increase in the open circuit voltage and a ~40% decrease in the contact resistance. The results from our new monolithic TEG show the potential of this TEG device architecture as a renewable power source for small sensors in various IoT applications.
In this work, we develop an alternative TEG device architecture that can be fabricated using a simple and low energy cost method. Monolithic TEGs consist of thin p- and n- type layers stacked together with an insulating spacer partially separating them. Using Cu- and Ag- chalcogenides possessing excellent RT TE properties, we were able to assemble monolithic TEGs using a simple and low energy cost process by co-sintering stacks of p-type Cu2+xSe, insulating Ag2S, and n-type Ag2SxSe1-x at low temperatures.
Previously, our TEGs suffered from high contact resistances, limiting the maximum power output of the devices. Using finite element method (FEM) simulations, the TEG device structure was optimized to increase the device voltage and decrease the contact resistance.
Our new TEG design replaced the pn-junction with a metal interconnect as the electrical contact between the p- and n-type TE layers and increased the maximum power density from 0.27 mW/cm2 to 0.68 mW/cm2 at a ΔT=30K. This was achieved by a small increase in the open circuit voltage and a ~40% decrease in the contact resistance. The results from our new monolithic TEG show the potential of this TEG device architecture as a renewable power source for small sensors in various IoT applications.