TY - JOUR
T1 - Fabrication of room temperature-stable 12CaO · 7Al 2 O 3 electride
T2 - A review
AU - Kim, Sung Wng
AU - Matsuishi, Satoru
AU - Miyakawa, Masashi
AU - Hayashi, Katsuro
AU - Hirano, Masahiro
AU - Hosono, Hideo
N1 - Funding Information:
Fig. 11 (a) Optical absorption spectra of as-grown C12A7 and Ca-treated C12A7 single crystals. The Ca treatment induces absorption bands peaking at 2.8 and 0.4 eV. With an increase in the Ca treatment duration, the peak intensities increase. (b) Diffuse reflectance spectra Fig. 12 X-band EPR spectrum of polycrystalline C12A7:e– with electron concentration of ~3 · 1019 cm–3 prepared by melt-solidification process. The carrier electron concentration was determined by electron paramagnetic spin resonance (EPR) using a Bruker E580 X-band (~9.7 GHz) spectrometer at RT. To avoid the skin depth effect due to carrier electrons, the samples were crushed into fine powders (~1 µm in diameter). The spin concentration was estimated by comparing the second integral of the spectrum with that of CuSO4 · 5H2O standard Acknowledgements This work was supported by a Grant-in-Aid for Creative Scientific Research (No. 16GS0205) from the Japanese Ministry of Education, Culture, Sports, Science and Technology
PY - 2007/10
Y1 - 2007/10
N2 - 12CaO · 7Al 2O 3 (C12A7) electride, which is synthesized by replacing free oxygen ions in cages with electron anions, has distinct advantages over electrides reported so far in respect of thermal and chemical stability and flexible preparation of various sample forms including single crystal, thin film, polycrystalline bulk and powder. These advantages, together with the fact that the concentration of the electron anions is controlled in a wide range according to a synthetic process, make the C12A7 electride attract growing attentions from both scientific and practical points of views. This paper reviews several chemical and physical synthetic processes of the C12A7 electride including thermal treatment of C12A7 under metal vapor and reducing gas atmospheres, hot Ar + ion implantation, solidification of the strongly reduced C12A7 melt, and crystallization of the reduced glass in vacuum. Each process, having its own suitability for a specific form of the electride, has unique advantages such as a completeness of anion replacement, mass production capability and controllability of the electron-doped area. Electronic and optical properties of the resulting electrides prepared by the different process are briefly discussed in terms of the feature of the processes.
AB - 12CaO · 7Al 2O 3 (C12A7) electride, which is synthesized by replacing free oxygen ions in cages with electron anions, has distinct advantages over electrides reported so far in respect of thermal and chemical stability and flexible preparation of various sample forms including single crystal, thin film, polycrystalline bulk and powder. These advantages, together with the fact that the concentration of the electron anions is controlled in a wide range according to a synthetic process, make the C12A7 electride attract growing attentions from both scientific and practical points of views. This paper reviews several chemical and physical synthetic processes of the C12A7 electride including thermal treatment of C12A7 under metal vapor and reducing gas atmospheres, hot Ar + ion implantation, solidification of the strongly reduced C12A7 melt, and crystallization of the reduced glass in vacuum. Each process, having its own suitability for a specific form of the electride, has unique advantages such as a completeness of anion replacement, mass production capability and controllability of the electron-doped area. Electronic and optical properties of the resulting electrides prepared by the different process are briefly discussed in terms of the feature of the processes.
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U2 - 10.1007/s10854-007-9183-y
DO - 10.1007/s10854-007-9183-y
M3 - Article
AN - SCOPUS:34547570012
SN - 0957-4522
VL - 18
SP - 5
EP - 14
JO - Journal of Materials Science: Materials in Electronics
JF - Journal of Materials Science: Materials in Electronics
IS - SUPPL. 1
ER -