TY - JOUR
T1 - Large-area implementation and critical evaluation of the material and fabrication aspects of a thin-film thermoelectric generator based on aluminum-doped zinc oxide
AU - Tappura, Kirsi
AU - Juntunen, Taneli
AU - Jaakkola, Kaarle
AU - Ruoho, Mikko
AU - Tittonen, Ilkka
AU - Ritasalo, Riina
AU - Pudas, Marko
N1 - | openaire: EC/H2020/645241/EU//TransFlexTeg
PY - 2020/3
Y1 - 2020/3
N2 - A large-area thermoelectric generator (TEG) utilizing a folded thin-film concept is implemented and the performance evaluated for near room temperature applications having modest temperature gradients (<50 K). The TEGs with the area of ∼0.33 m2 are shown capable of powering a wireless sensor node of multiple sensors suitable e.g. for monitoring environmental variables in buildings. The TEGs are based on a transparent, non-toxic and abundant thermoelectric material, i.e. aluminium-doped zinc oxide (AZO), deposited on flexible substrates. After folding, both the electrical current and heat flux are in the plane of the thermoelectric thin-film. Heat leakage in the folded TEG is shown to be minimal (close to that of air), enabling sufficient temperature gradients without efficient heat sinks, contrary to the conventional TEGs having the thermal flux and electrical current perpendicular to the plane of the thermoelectric films. The long-term stability studies reveal that there are no significant changes in the electrical or thermoelectric properties of AZO over several months, while the contact resistance between AZO and silver ink is an issue exhibiting a continuous increase over time. The performance of the TEGs and technological implications in relation to a state-of-the-art thermoelectric material are further assessed via a computational study.
AB - A large-area thermoelectric generator (TEG) utilizing a folded thin-film concept is implemented and the performance evaluated for near room temperature applications having modest temperature gradients (<50 K). The TEGs with the area of ∼0.33 m2 are shown capable of powering a wireless sensor node of multiple sensors suitable e.g. for monitoring environmental variables in buildings. The TEGs are based on a transparent, non-toxic and abundant thermoelectric material, i.e. aluminium-doped zinc oxide (AZO), deposited on flexible substrates. After folding, both the electrical current and heat flux are in the plane of the thermoelectric thin-film. Heat leakage in the folded TEG is shown to be minimal (close to that of air), enabling sufficient temperature gradients without efficient heat sinks, contrary to the conventional TEGs having the thermal flux and electrical current perpendicular to the plane of the thermoelectric films. The long-term stability studies reveal that there are no significant changes in the electrical or thermoelectric properties of AZO over several months, while the contact resistance between AZO and silver ink is an issue exhibiting a continuous increase over time. The performance of the TEGs and technological implications in relation to a state-of-the-art thermoelectric material are further assessed via a computational study.
KW - large-area thermoelectric generator
KW - thin-film TEG
KW - aluminum-doped zinc oxide
KW - finite element method
KW - atomic layer deposition
UR - http://www.scopus.com/inward/record.url?scp=85072577550&partnerID=8YFLogxK
U2 - 10.1016/j.renene.2019.09.093
DO - 10.1016/j.renene.2019.09.093
M3 - Article
SN - 0960-1481
VL - 147
SP - 1292
EP - 1298
JO - Renewable Energy
JF - Renewable Energy
ER -