More Like this

1. Stencil-Printed Scalable Radial Thermoelectric Device Using Sustainable Manufacturing Methods

   https://doi.org/10.3390/su16093560  

   Jang, Eunhwa; Ambade, Rohan B; Banerjee, Priyanshu; Topoleski, LD Timmie; Madan, Deepa (May 2024, Sustainability)

   In this study, we used n-chitosan-Bi2Te2.7Se0.3 and p-chitosan-Bi0.5Sb1.5Te3 composite inks to print a circular thermoelectric generator (TEG) device using a low-energy-input curing method. Thermoelectric (TE) composite films were fabricated using varying sizes of thermoelectric particles and a small chitosan binder (0.05 wt. %). The particles and binder were hot pressed at an applied pressure of 200 MPa and cured at 200 °C for 30 min. We achieved ZT of 0.35 for the n-type and 0.7 for the p-type TE composite films measured at room temperature. A radial TEG was fabricated using the best-performing n-type and p-type composite inks and achieved a power output of 87 µW and a power density of 727 µW/cm2 at a temperature difference of 35 K; these are among the best-reported values for printed TEG devices. Using a low-energy-input fabrication method, we eliminated the need for high-temperature and long-duration curing processes to fabricate printing devices. Thus, we envisage that the low-energy-input curing process and cost-effective printable strategy presented in this work pave the way for sustainable manufacturing of large-scale energy harvesting TEG devices. 

   more » « less
2. Recent advances in printable thermoelectric devices: materials, printing techniques, and applications

   https://doi.org/10.1039/C9RA09801A  

   Hossain, Md Sharafat; Li, Tianzhi; Yu, Yang; Yong, Jason; Bahk, Je-Hyeong; Skafidas, Efstratios (February 2020, RSC Advances)

   Thermoelectric devices have great potential as a sustainable energy conversion technology to harvest waste heat and perform spot cooling with high reliability. However, most of the thermoelectric devices use toxic and expensive materials, which limits their application. These materials also require high-temperature fabrication processes, limiting their compatibility with flexible, bio-compatible substrate. Printing electronics is an exciting new technique for fabrication that has enabled a wide array of biocompatible and conformable systems. Being able to print thermoelectric devices allows them to be custom made with much lower cost for their specific application. Significant effort has been directed toward utilizing polymers and other bio-friendly materials for low-cost, lightweight, and flexible thermoelectric devices. Fortunately, many of these materials can be printed using low-temperature printing processes, enabling their fabrication on biocompatible substrates. This review aims to report the recent progress in developing high performance thermoelectric inks for various printing techniques. In addition to the usual thermoelectric performance measures, we also consider the attributes of flexibility and the processing temperatures. Finally, recent advancement of printed device structures is discussed which aims to maximize the temperature difference across the junctions. 

   more » « less
3. 3D Conformal Printing and Photonic Sintering of High‐Performance Flexible Thermoelectric Films Using 2D Nanoplates

   https://doi.org/10.1002/adfm.201901930  

   Saeidi‐Javash, Mortaza; Kuang, Wenzheng; Dun, Chaochao; Zhang, Yanliang (July 2019, Advanced Functional Materials)

   Abstract Flexible thermoelectric (TE) devices hold great promise for energy harvesting and cooling applications, with increasing significance to serve as perpetual power sources for flexible electronics and wearable devices. Despite unique and superior TE properties widely reported in nanocrystals, transforming these nanocrystals into flexible and functional forms remains a major challenge. Herein, demonstrated is a transformative 3D conformal aerosol jet printing and rapid photonic sintering process to print and sinter solution‐processed Bi₂Te_2.7Se_0.3nanoplate inks onto virtually any flexible substrates. Within seconds of photonic sintering, the electrical conductivity of the printed film is dramatically improved from nonconductive to 2.7 × 10⁴S m⁻¹. The films demonstrate a room temperature power factor of 730 µW m⁻¹K⁻², which is among the highest values reported in flexible TE films. Additionally, the film shows negligible performance changes after 500 bending cycles. The highly scalable and low‐cost fabrication process paves the way for large‐scale manufacturing of flexible devices using a variety of high‐performing nanoparticle inks. 

   more » « less
4. Additive Manufacturing of Polymer Matrix Composite Materials with Aligned or Organized Filler Material: A Review

   https://doi.org/10.1002/adem.202001002  

   Niendorf, Karl; Raeymaekers, Bart (January 2021, Advanced Engineering Materials)

   The ability to fabricate polymer matrix composite materials with continuous or discontinuous filler material, oriented in a user‐specified direction, enables implementing designer material properties, such as anisotropic mechanical, thermal, and electrical properties. Conventional fabrication methods rely on a mold, which limits specimen geometry and is difficult to implement. In contrast, additive manufacturing, including fused filament fabrication or fused deposition modeling, direct ink writing, or stereolithography, combined with a method to align filler material such as a mechanical force or an electric, magnetic, shear force, or ultrasound wave field, enables 3D printing polymer matrix composite material specimens with complex geometry and aligned filler material, without the need for a mold. Herein, we review the combinations of fabrication and filler material alignment methods used to fabricate polymer matrix composite materials, in terms of operating and design parameters including size, resolution, print speed, filler material alignment time, polymer matrix and filler material requirements, and filler manipulation requirements. The operating envelope of each fabrication method is described and their advantages, disadvantages, and limitations are discussed. Finally, different combinations of 3D printing and filler material alignment methods in the context of important engineering applications, such as structural materials, flexible electronics, and shape‐changing materials, are illustrated. 

   more » « less
5. Printing thermoelectric inks toward next-generation energy and thermal devices

   https://doi.org/10.1039/d1cs00490e  

   Zeng, Minxiang; Zavanelli, Duncan; Chen, Jiahao; Saeidi-Javash, Mortaza; Du, Yipu; LeBlanc, Saniya; Snyder, G. Jeffrey; Zhang, Yanliang (January 2022, Chemical Society Reviews)

   The ability of thermoelectric (TE) materials to convert thermal energy to electricity and vice versa highlights them as a promising candidate for sustainable energy applications. Despite considerable increases in the figure of merit zT of thermoelectric materials in the past two decades, there is still a prominent need to develop scalable synthesis and flexible manufacturing processes to convert high-efficiency materials into high-performance devices. Scalable printing techniques provide a versatile solution to not only fabricate both inorganic and organic TE materials with fine control over the compositions and microstructures, but also manufacture thermoelectric devices with optimized geometric and structural designs that lead to improved efficiency and system-level performances. In this review, we aim to provide a comprehensive framework of printing thermoelectric materials and devices by including recent breakthroughs and relevant discussions on TE materials chemistry, ink formulation, flexible or conformable device design, and processing strategies, with an emphasis on additive manufacturing techniques. In addition, we review recent innovations in the flexible, conformal, and stretchable device architectures and highlight state-of-the-art applications of these TE devices in energy harvesting and thermal management. Perspectives of emerging research opportunities and future directions are also discussed. While this review centers on thermoelectrics, the fundamental ink chemistry and printing processes possess the potential for applications to a broad range of energy, thermal and electronic devices. 

   more » « less