2013 Fiscal Year Final Research Report
Study on synthesis method for core-shell type cluster and novel functions by the surface and interface effects
Project/Area Number |
23560785
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Physical properties of metals
|
Research Institution | Nagoya Institute of Technology |
Principal Investigator |
HIHARA Takehiko 名古屋工業大学, 工学(系)研究科(研究院), 教授 (60324480)
|
Project Period (FY) |
2011 – 2013
|
Keywords | 複合ナノ粒子 / 超伝導 / 燃料電池 / 触媒 / パーコレーション |
Research Abstract |
Sn/Si and Ag/Si composite nanoparticle assembled films were prepared by a plasma-gas-condensation cluster beam deposition apparatus. Transmission electron microscope images indicated that individual nanoparticles have composite morphologies. Their electrical resistivity exhibits the onset of superconducting transition below 6.1 K (for 12at%Si). The increased TC is attributable to exciton-type superconductivity. The superconducting critical magnetic fields, Hc, were also measured and found to be higher than the critical magnetic field of the bulk Sn. The electrical conductivity of Ag/Si nanoparticle assembled films obeys a power law of the Ag concentration pAg. The dramatic change at around pAg = pc, indicates that the percolation of Ag nanoparticles takes place at the threshold value pc. Moreover, we found that the Hall-coefficient |RH| at T = 5 K of Ag/Si nanoparticle assembled film with the closest pAg to p¬c is 20 times higher than that of the bulk Ag.
|