Cu2Se-based thermoelectric cellular architectures for efficient and durable power generation

Thermoelectric power generation offers a promising way to recover waste heat. The geometrical design of thermoelectric legs in modules is important to ensure sustainable power generation but cannot be easily achieved by traditional fabrication processes. Herein, we propose the design of cellular thermoelectric architectures for efficient and durable power generation, realized by the extrusion-based 3D printing process of Cu2Se thermoelectric materials. We design the optimum aspect ratio of a cuboid thermoelectric leg to maximize the power output and extend this design to the mechanically stiff cellular architectures of hollow hexagonal column- and honeycomb-based thermoelectric legs. Moreover, we develop organic binder-free Cu2Se-based 3D-printing inks with desirable viscoelasticity, tailored with an additive of inorganic Se-8(2-) polyanion, fabricating the designed topologies. The computational simulation and experimental measurement demonstrate the superior power output and mechanical stiffness of the proposed cellular thermoelectric architectures to other designs, unveiling the importance of topological designs of thermoelectric legs toward higher power and longer durability

Synthesis of soluble chalcogens and metal chalcogenides for thermoelectric and electronic applications

Department of Materials Science and Engineeringclos

High-performance Thermoelectric Inks for Power Generation Application

Output power of thermoelectric generators depends on device engineering minimizing heat loss as well as inherent material properties. However, the device engineering has been largely neglected due to the limited flat or angular shape of devices. Considering that the surface of most heat sources where these planar devices are attached is curved, a considerable amount of heat loss is inevitable. To address this issue, here, we present the shapeconformable thermoelectric materials geometrically to surfaces of any shape by securing the flexibility of thin films or painting and 3D printing processes. We synthesized the molecular Sb2Te3 chalcogenidometallate and utilize them as ink solution for fabricating flexible thin films. At the same time, we prepared Bi2Te3-based inorganic pastes by using Sb2Te3 chalcogenidometallate as an additive for Bi2Te3-based thermoelectric particles, with ZT values of 0.5~0.7 for n-type and 1.0~1.2 for p-type materials that compete the bulk values. Devices directly brush-painted onto curved surfaces produced the high output power of 4.0 mW cm-2 under the temperature difference of 50 oC. Also, the shapes of 3D blocks printed by dispensing process were controllably varied to cube, circle, and half ring. Half-ring shaped thermoelectric 3D blocks were used to fabricate the cylindrical power generating module with three n-type and p-type pairs, which exhibited mW-level power under the temperature difference of 30~40 oC. These approaches pave the way to designing materials and devices that can be easily transferred to other applications

High Performance Shape-Conformable Thermoelectric Materials and Devices to Heat Sources

Here, we present the shape-conformable thermoelectric materials geometrically to surfaces of any shape by securing the flexibility of thin films or painting and 3D printing processes. We synthesized the molecular Sb2Te3 chalcogenidometallate and utilize them as ink solution for fabricating flexible thin films. At the same time, we prepared Bi2Te3-based inorganic pastes by using Sb2Te3 chalcogenidometallate as an additive for Bi2Te3-based thermoelectric particles, with ZT values of 0.5~0.7 for n-type and 1.0~1.2 for p-type materials that compete the bulk values. Devices directly brush-painted onto curved surfaces produced the high output power of 4.0 mW cm-2 under the temperature difference of 50 oC. Also, the shapes of 3D blocks printed by dispensing process were controllably varied to cube, circle, and half ring

Ink Processing for Thermoelectric Materials and Power???Generating Devices

The growing concern over the depletion of hydrocarbon resources, and the adverse environmental effects associated with their use, has increased the demand for renewable energy sources. Thermoelectric (TE) power generation from waste heat has emerged as a renewable energy source that does not generate any pollutants. Recently, ink-based processing for the preparation of TE materials has attracted tremendous attention because of the simplicity in design of power generators and the possibility of cost-effective manufacturing. In this progress report, recent advances in the development of TE inks, processing techniques, and ink-fabricated devices are reviewed. A summary of typical formulations of TE materials as inks is included, as well as a discussion on various ink-based fabrication methods, with several examples of newly designed devices fabricated using these techniques. Finally, the prospects of this field with respect to the industrialization of TE power generation technology are presented