Serrano-Claumarchirant José F, Hamawandi Bejan, Ergül Adem B, Cantarero Andrés, Gómez Clara M, Priyadarshi Pankaj, Neophytou Neophytos, Toprak Muhammet S
Department of Applied Physics, KTH Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
School of Engineering, University of Warwick, Coventry CV4 7AL, U.K.
ACS Appl Mater Interfaces. 2022 May 4;14(17):19295-19303. doi: 10.1021/acsami.1c24392. Epub 2022 Apr 22.
Thermoelectric (TE) materials can have a strong benefit to harvest thermal energy if they can be applied to large areas without losing their performance over time. One way of achieving large-area films is through hybrid materials, where a blend of TE materials with polymers can be applied as coating. Here, we present the development of all solution-processed TE ink and hybrid films with varying contents of TE SbTe and BiTe nanomaterials, along with their characterization. Using (1-methoxy-2-propyl) acetate (MPA) as the solvent and poly (methyl methacrylate) as the durable polymer, large-area homogeneous hybrid TE films have been fabricated. The conductivity and TE power factor improve with nanoparticle volume fraction, peaking around 60-70% solid material fill factor. For larger fill factors, the conductivity drops, possibly because of an increase in the interface resistance through interface defects and reduced connectivity between the platelets in the medium. The use of dodecanethiol (DDT) as an additive in the ink formulation enabled an improvement in the electrical conductivity through modification of interfaces and the compactness of the resultant films, leading to a 4-5 times increase in the power factor for both p- and n-type hybrid TE films, respectively. The observed trends were captured by combining percolation theory with analytical resistive theory, with the above assumption of increasing interface resistance and connectivity with polymer volume reduction. The results obtained on these hybrid films open a new low-cost route to produce and implement TE coatings on a large scale, which can be ideal for driving flexible, large-area energy scavenging technologies such as personal medical devices and the IoT.
如果热电（TE）材料能够大面积应用且性能不会随时间衰减，那么它们在收集热能方面将具有显著优势。实现大面积薄膜的一种方法是通过混合材料，即将TE材料与聚合物混合后作为涂层应用。在此，我们展示了全溶液处理的TE墨水以及含有不同含量TE SbTe和BiTe纳米材料的混合薄膜的开发及其表征。使用乙酸（1-甲氧基-2-丙基）酯（MPA）作为溶剂，聚（甲基丙烯酸甲酯）作为耐用聚合物，制备出了大面积均匀的混合TE薄膜。电导率和TE功率因数随纳米颗粒体积分数的增加而提高，在固体材料填充率约为60 - 70%时达到峰值。对于更大的填充率，电导率下降，这可能是由于界面缺陷导致界面电阻增加以及介质中薄片之间的连通性降低所致。在墨水配方中使用十二烷硫醇（DDT）作为添加剂，通过修饰界面和提高所得薄膜的致密性，使电导率得到改善，分别导致p型和n型混合TE薄膜的功率因数提高了4 - 5倍。通过将渗流理论与解析电阻理论相结合，并基于上述随着聚合物体积减小界面电阻和连通性增加的假设，捕捉到了观察到的趋势。这些混合薄膜的研究结果为大规模生产和应用TE涂层开辟了一条新的低成本途径，这对于推动诸如个人医疗设备和物联网等灵活的大面积能量收集技术而言可能是理想之选。
