Thermoelectric properties of Si-NiSi2 Nanocomposite with coherent grain boundaries

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K18233
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Structural/Functional materials
• Research Institution: Osaka University
• Principal Investigator: Ohishi Yuji 大阪大学, 工学研究科, 助教 (20571558)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 熱電材料 / ナノ構造化 / シリコン / 液体急冷法

Outline of Final Research Achievements

Si-CoSi2 composite material was synthesized by meltspinning Si, B and Co. B was added as a donar. The size of CoSi2 was found to be 100-500 nm. Since the lattice parameter of CoSi2 is close to that of Si, less effect on the electrical property is expected. The thermoelectric properties of this composite was measured and compared to those of the sample containing the same amount of CoSi2 with micro size. The measurement revealed that although there was no significant change in the electrical conductivity and Seebeck coefficient, reduction in the lattice thermal conductivity was observed in the sample with nano-sized precipitation of CoSi2. As a result, 16% improvement in the thermoelectric figure of merit, ZT was achieved. This result suggest that finer CoSi2 precipitates may lead to the higher ZT.

Free Research Field

エネルギー材料