TY - JOUR
T1 - Highly Porous Magnesium Silicide Honeycombs Prepared by Magnesium Vapor Annealing of Silica-Coated Polymer Honeycomb Films toward Ultralightweight Thermoelectric Materials
AU - Yabu, Hiroshi
AU - Matsuo, Yasutaka
AU - Yamada, Takahiro
AU - Maeda, Hirotaka
AU - Matsui, Jun
N1 - Funding Information:
This research has been supported in part by KAKENHI, the Japan Society for the Promotion of Science (JSPS) (Nos. 18H05482, 19KK0357).
Funding Information:
H.Y. thanks Ms. Minori Suzuki, Mrs. Mayumi Sasaki, and Ms. Shizuka Miyamoto, WPI-AIMR, Tohoku University, for assisting with sample preparation and SEM observations. H.Y. also thanks the Cooperative Research Program of “NJRC Mater. & Dev”, MEXT, Japan, and Mrs. Ayano Yamazaki for assistance with XPS. This work was also supported in part by “Five-star Alliance”, MEXT, Japan.
Publisher Copyright:
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PY - 2020/12/8
Y1 - 2020/12/8
N2 - Magnesium silicide (Mg2Si) is one of the few thermoelectric materials that is composed of high Clark number elements and exhibits an optimum temperature near 700 K. The advantage of Mg2Si is that it is composed of universal elements and can be synthesized at low cost. However, it has the disadvantage of low efficiency in converting heat flow to electricity due to its high thermal conductivity. In this paper, Mg vapor annealing of silica-coated 1,2-polybutadiene honeycomb films enables the formation of a Mg2Si honeycomb supported by amorphous carbon. The annealing temperature should be greater than 998 K to obtain Mg2Si honeycombs, and we confirmed through detailed chemical analysis that a silica layer can be converted to a Mg2Si layer via formation of Si. Furthermore, the honeycomb structure eventually reduced the thermal diffusivity even though only a single layer of the honeycomb structure formed on the surface. The obtained Mg2Si honeycombs are good candidates for effective and low-cost thermoelectric materials for use in high-temperature applications.
AB - Magnesium silicide (Mg2Si) is one of the few thermoelectric materials that is composed of high Clark number elements and exhibits an optimum temperature near 700 K. The advantage of Mg2Si is that it is composed of universal elements and can be synthesized at low cost. However, it has the disadvantage of low efficiency in converting heat flow to electricity due to its high thermal conductivity. In this paper, Mg vapor annealing of silica-coated 1,2-polybutadiene honeycomb films enables the formation of a Mg2Si honeycomb supported by amorphous carbon. The annealing temperature should be greater than 998 K to obtain Mg2Si honeycombs, and we confirmed through detailed chemical analysis that a silica layer can be converted to a Mg2Si layer via formation of Si. Furthermore, the honeycomb structure eventually reduced the thermal diffusivity even though only a single layer of the honeycomb structure formed on the surface. The obtained Mg2Si honeycombs are good candidates for effective and low-cost thermoelectric materials for use in high-temperature applications.
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U2 - 10.1021/acs.chemmater.0c03696
DO - 10.1021/acs.chemmater.0c03696
M3 - Article
AN - SCOPUS:85097843310
SN - 0897-4756
VL - 32
SP - 10176
EP - 10183
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 23
ER -