High-performance μ-thermoelectric device based on Bi2Te3/Sb2Te3 p-n junctions

A flexible and ultralight planar thermoelectric generator based on 15 thermocouples composed of n-type bismuth telluride (Bi2Te3) and p-type antimony telluride (Sb2Te3) legs (each with 400 nm thick) connected in series, on 25 μm thick Kapton substrate, was fabricated with impressive power factor val...

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Detalhes bibliográficos
Autor principal: Vieira, Eliana Maria Fernandes (author)
Outros Autores: Pires, A. L. (author), Silva, José Pedro Basto (author), Magalhães, V. H. (author), Grilo, J. (author), Brito, F.P. (author), Silva, M. F. (author), Pereira, A. M. (author), Gonçalves, L. M. (author)
Formato: article
Idioma:eng
Publicado em: 2019
Assuntos:
Texto completo:http://hdl.handle.net/1822/62678
País:Portugal
Oai:oai:repositorium.sdum.uminho.pt:1822/62678
Descrição
Resumo:A flexible and ultralight planar thermoelectric generator based on 15 thermocouples composed of n-type bismuth telluride (Bi2Te3) and p-type antimony telluride (Sb2Te3) legs (each with 400 nm thick) connected in series, on 25 μm thick Kapton substrate, was fabricated with impressive power factor values of 2.7 and 0.8 mW K-2 m-1 (at 298 K) for Bi2Te3 and Sb2Te3 films, respectively. The p-n junction thermoelectric device can generate a maximum open-circuit voltage and output power of 210 mV and 0.7 μW (3.3 mW cm-2), respectively, for a temperature difference of 35 K, which is higher than the one observed for a conventional thermoelectric device with metallic contacts for p-n junctions. The results were combined with numerical simulations, showing a good match between the experimental and the numerical results. The current density versus voltage (J-V) characteristics of the fabricated p-n junctions revealed a diode behavior with a turn-on voltage of ≈0.3 V and an impressive rectifying ratio (I+1V/I-1V) of ≈2 × 104.