http://www.tagen.tohoku.ac.jp/labo/muramatsu/mura/main.html E-mail: mura@tagen.tohoku.ac.jp 1
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3 1m 10cm 1cm 1mm 100 m 10 m 1 m 100nm 10nm 1nm 1 100 m 10 m 1 m 1nm 100nm 10nm
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10 9 m = 1 nm m 8
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A S 4 = 4πr 2, V = πr 3 3 = A S = 3 Vd rd ( d ) 11
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ゲルーゾル法で合成した粒子 α-fe2o3 α-fe2o3 CdS 2μm 2μm 2μm 10μm Cu2O CdS 0.5μm α-fe2o3 α-fe2o3 1μm 0.5μm 15
-Fe 2 O 3 m 16
Stöber 17
1. 2. 3. (T. Sugimoto, Adv. Colloid Interface Sci. 28, 65 (1987).) 18
LaMer 19
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O 22
Si(-O-C 2 H 5 ) 4 + 2H 2 O SiO 2 + 4C 2 H 5 OH 23
Stöber TEOS=Tetraethylorthosilica te, Si(-O-C 2 H 5 ) 4 0.1 0.5 mol/l = NH 3 =1 10 mol/l H2O= 0.5 2.0 mol/l = 0 30 24
TiO 2, ZrO 2 SiO2: W. Stöber, A. Fink, and E. Bohn: J. Colloid Interface Sci. 26, (1968) 62. TiO2: E.A. Barringer and H.K. Bowen: J. Am. Ceram. Soc. 67 (1984) C-113. E. A. Barringer, N. Jubb, B. Fegley, Jr., R. L. Pober, and H. K. Bowen: in "Ultrastructure Processing of Ceramics, Glasses, and Composites," (L. L. Hench and D. R. Ulrich, Eds.), pp. 315-333. Wiley, New York, 1984. B. Fegley, Jr., E. A. Barringer, and H. K. Bowen: J. Am. Ceram. Soc. 67, (1984) C-113. ZrO2: K. Uchiyama, T. Ogihara, T. Ikemoto, N. Mizutani, and M. Kato: J. Mater. Sci. 22, (1987) 4343. T. Ogihara, N. Mizutani, and M. Kato: Ceram. Intern. 13, (1987) 35. PZT: T. Ogihara, H. Kaneko, N. Mizutani, and M. Kato: J. Mater. Sci. Lett. 7, (1988) 867. H. Hirashima, E. Onishi, and M. Nakagawa: J. Non- Cryst. Solids 121, (1990) 404. 25
Matijevic 26
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α-fe2o3 -FeOOH α-fe 2 O 3 28
1 mol/l 1/100 mol/l 29
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100 Fe(OH)3 β-feooh 3 hours 6 days α-fe2o3 32
2μm 33
Ni(OH)2 With PEG 50,, 12 hours NaH2PO2 0.1 M Ni(OH) 2 + 4 M NaH 2 PO 2 0.5 wt% PEG 400,000 34
- : 0.5 M : 1.0 M 2M 35
Reservoir of M 2+ Reservoir of S 2- Cd(OH)2 or Metal chelates M(NH3)n 2+ 2+ 2- M + S Gelatin TAA M=Cd, Zn, Pb etc. 36
BaTiO 3, SrTiO 3 37
Synthesis method of BaTiO 3 /SrTiO 3 fine particles H) 3 gel-sol method Schematic drawing of reaction vessel (autoclave) 38
TEM micrograph of BaTiO 3 BT01 BT02 (High Purity Chemicals) 200 nm BT03 (Wako Pure Chemicals) 39
XRD patterns of starting materials a. BT01 Intensity/a.u. b. BT02 c. BT03 BaTiO 3 (cub., JCPDS 31-174) BaTiO 3 (tet., JCPDS 5-0626) 10 20 30 40 50 60 2θ/degree 40
TG curves for starting materials in Ar 0-0.6 BT03 BT02-0.05 Weight change/% -1-2 -3 BT01 Samples: BaTiO 3 Heating rate: 5 ºC/min, in argon atmosphere -1.7-4 0 100 200 300 400 500 600 700 800 900 1000 Temperature/ºC 41
TEM microphotographs of initial materials 50 nm 200 nm 200 nm SR-01 SR-02 SR-03 The particle size of SR-01 is smaller than 40 nm. 42
XRD patterns for initial materials a. SR-01 Intensity/a.u. b. SR-02 c. SR-03 SrTiO 3 (Cub., JCPDS 35-734) 10 20 30 40 50 60 2θ/degree A cubic SrTiO 3 phase was founded in initial materials. 43
TG curves of initial materials in Ar atmosphere Weight change/% 0-2 -4-6 -8-10 -3.9 SR-01 SR-02 Samples: SrTiO 3 Heating rate: 5 ºC/min, in argon atmosphere 0 250 500 750 1000 Temperature/ºC SR-03-0.90-6.73 Carbonates SR-01 only contents 3.9 % of adsorbed water and 2.83 % of OH groups. 44
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CeO 2 1.0x10-3 mol/l Ce(SO 4 ) 2 4.0x10-2 mol/l H 2 SO 4 90 A B,C B 46
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2.0x10-2 mol dm -3 FeCl 3 and 4.5x10-4 KH 2 PO 4 at 100 o C M. Ocana, M. Morales, and C.J. Serna: J. Colloid Interface Sci. 171 (1995) 85. M. Ocana, R. Rodriguez-Clemente, C.J. Serna: Adv. Mater. 7 (1995) 212. 49
0 hour 8 hours 2 day 4 day 7 day β-feooh α-fe 2 O 3 50