SILICON BULK THERMOELECTRIC CONVERSION MATERIAL
|Posted date||Jul 29, 2019|
|International application number||2018JP047940|
|International publication number||WO 2019131795|
|Date of international filing||Dec 26, 2018|
|Date of international publication||Jul 4, 2019|
|Title||SILICON BULK THERMOELECTRIC CONVERSION MATERIAL|
|Abstract||Provided is a silicon bulk thermoelectric conversion material for which thermoelectric performance is improved over the prior art by reducing the thermal conductivity of silicon. In the silicon bulk thermoelectric conversion material, the ZT exceeds 0.2 at room temperature with silicon alone. The silicon bulk thermoelectric conversion material has a plurality of silicon grains measuring 1-300 nm, first voids measuring 1-30 nm on average that are present in the plurality of silicon grains and on the surfaces of the silicon grains, and second voids measuring 100-300 nm on average that are present between the plurality of silicon grains. The silicon grains have an aspect ratio of less than 10.|
|Outline of related art and contending technology||
In recent years, aiming at improvement of the performance of the thermoelectric conversion material has been research. The thermoelectric conversion is, mutual conversion between heat and electricity and a device capable of directly, this makes it possible to use waste heat from a cold heat source of such is difficult to generate electricity from the can, including a power source such as IoT of sensing device has attracted attention as an energy harvesting device. The performance of the thermoelectric conversion material, represented by the dimensionless performance index ZT.
In this case, S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature, κ is thermal conductivity. As is clear from this equation, the performance of the thermoelectric conversion material, (1) Seebeck coefficient or electrical conductivity or to improve the σ S, (2) which reduces the thermal conductivity κ, can be improved by any of the.
The group of research in recent years, the ZT is significantly greater than the 1 reported research. On the other hand, when considering the use as energy harvesting device, a significant improvement in ZT is not absolutely necessary, the manufacturing cost can be reduced if high ZT is not necessarily required. However, reported so far most of the study, is highly toxic environmental adaptability of the expensive material or a material having a low used. Therefore, the cost-effectiveness of the above it is not possible to solve such a problem, with the popularization of thermoelectric conversion device, has not been put into practical use. In this case, when viewed from the viewpoint of production cost, the amount of silicon is buried in the high, non-toxicity, a material having a high stability, and currently in widespread use can be can be applied to the silicon processing technology, a promising material as a thermoelectric conversion material. However, silicon has a thermal conductivity of 100 W/m/K or higher, the thermoelectric conversion material may be a simple and practical at all about ZT value is 0.005 at present is not suitable. Therefore, Patent Document 1 is' an aspect ratio greater than 10' and having a thermal conductivity of the nanowires so as to reduce by (claim 1, such as paragraph 0009). In addition, Patent Document 2 is' magnesium, silicon alloy, magnesium, silicon, tin, silicon, or silicon, and germanium alloy as a main component, having a large number of minute holes can be made of a porous body and the thermoelectric material ' are means for solving, this is because, a single small silicon or doped silicon is not practical from the obtained ZT value, based on the alloy material (such as germanium) thermoelectric material means that the seeking.
|Scope of claims||
|IPC(International Patent Classification)||
National States: AE AG AL AM AO AT AU AZ BA BB BG BH BN BR BW BY BZ CA CH CL CN CO CR CU CZ DE DJ DK DM DO DZ EC EE EG ES FI GB GD GE GH GM GT HN HR HU ID IL IN IR IS JO JP KE KG KH KN KP KR KW KZ LA LC LK LR LS LU LY MA MD ME MG MK MN MW MX MY MZ NA NG NI NO NZ OM PA PE PG PH PL PT QA RO RS RU RW SA SC SD SE SG SK SL SM ST SV SY TH TJ TM TN TR TT TZ UA UG US UZ VC VN ZA ZM ZW
ARIPO: BW GH GM KE LR LS MW MZ NA RW SD SL SZ TZ UG ZM ZW
EAPO: AM AZ BY KG KZ RU TJ TM
EPO: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
OAPI: BF BJ CF CG CI CM GA GN GQ GW KM ML MR NE SN ST TD TG
|Reference ( R and D project )||CREST Scientific Innovation for Energy Harvesting Technology AREA|
Contact Information for " SILICON BULK THERMOELECTRIC CONVERSION MATERIAL "
- Japan Science and Technology Agency Department of Intellectual Property Management
- URL: http://www.jst.go.jp/chizai/
- Address: 5-3, Yonbancho, Chiyoda-ku, Tokyo, Japan , 102-8666
- Fax: 81-3-5214-8476