The 66th JSAP Spring Meeting, 2019

Presentation information

Oral presentation

13 Semiconductors » 13.2 Exploratory Materials, Physical Properties, Devices

[11p-W834-1~18] 13.2 Exploratory Materials, Physical Properties, Devices

Mon. Mar 11, 2019 1:15 PM - 6:30 PM W834 (W834)

Takashi Suemasu(Univ. of Tsukuba), Hirokazu Tatsuoka(Shizuoka Univ.), Kenji Yamaguchi(QST), Kosuke Hara(Univ. of Yamanashi)

5:00 PM - 5:15 PM

[11p-W834-14] Synthesis of Si-based Nanosheet Bundles using Metal Chlorides in Solutions

〇(D)Yalei Huang1, Vimal Saxena2, Kaito Tanaka3, Yasuhiro Hayakawa4, Hirokazu Tatsuoka2, Naohisa Takahashi5 (1.GSST Shizuoka Univ., 2.GSIST Shizuoka Univ., 3.Dpt. Eng. Shiz. Uni., 4.RIE Shizuoka Univ., 5.Yamaha Ad. Ma. Re. G)

Keywords:Si-based nanosheet, metal chlorides, chemical reaction

Introduction: A nanosheet bundle is one of the important structures for technological applications, such as thermoelectricity, and use in solar cells and Li-ion batteries. In this paper, the nanosheet bundle is defined as an aggregate of long nanosheets that are highly oriented, well-aligned, dense and tied together in higher densities. It has been demonstrated that Si-based nanosheet bundles can be prepared. The synthesis of Si nanosheet bundles by extraction of the Ca atoms from CaSi2 crystals using Inositol hexakisphosphate (IP6) has been reported [1]. The structural property of the resultant Si-based nanosheet bundles depends on reactant agents with CaSi2 and solutions, and it is affected by the exfoliation mechanism of the Ca atoms from the CaSi2 crystals. In this paper, synthesis of Si-based nanosheet bundles from CaSi2 using selected chloride compounds is reported.
Experiments: Commercially-available CaSi2 crystal powders were used as the source material. The Si-based nanosheet bundles were formed by Ca-atom extraction from the CaSi2 crystals by chemical reactions with CuCl2, TiCl3, RuCl3, H2PtCl6 and their related compounds in aqueous, dilute HCl acid and propylene carbonate (PC) solutions. The structural properties of these nanostructure bundles were characterized and compared to each other.
Results and Discussion: Figure 1 shows TEM images of Si-based nanosheets bundles synthesized with TiCl3, RuCl3 and H2PtCl6 in aqueous solution and CuCl2 in PC solution. For the case of TiCl3, the formation of the bundle structures is observed by the exfoliation of the sheets each other. In addition, stripped pattern along the sheet surface is also observed. For RuCl3, and H2PtCl6, metallic precipitation is additionally observed. Metallic precipitation with large size distribution is also observed for CuCl2 in PC solution. The atomic scale structural modifications from CaSi2 crystals will be also presented.