Page 143 - Book Hosokawa Nanoparticle Technology Handbook

3.2 SINGLE NANOPARTICLE MOTION IN FLUID FUNDAMENTALS
modification process including reactions in reversed [9] S.O’Brien, L. Brus and C.B. Murray, J. Am. Chem.
micelles [8], sol-gel reactions of metal alkoxides with Soc., 123, 12085 (2001).
existence of capping agents [9], non-hydrolytic sol-gel [10] T.J. Trentler, T.E. Denler, J.F. Bertone, A. Agrawal and
reactions of metal halides with capping agents [10], V.K. Colvin, J. Am. Chem. Soc., 121, 1613 (1999).
and thermal decomposition of metal complexes [11]. [11] J. Rockenberger, E.C. Scher and A.P. Alivisatos,
Since these processes prepared nanoparticle in a J. Am. Chem. Soc., 121, 11595 (1999).
nanoscaled liquid poor using organic compound the [12] H. Kamiya, K. Gomi, Y. Iida, K. Tanaka, T. Yoshiyasu
organic surfactant groups remained on particle surface
and well dispersed particles were obtained. However, and T. Kakiuchi, J. Am. Ceram. Soc., 86(12),
since most studies of the above process such as modi- 2011–2018 (2003).
fied reverse micelle method have been made under [13] J. Park, K. Au, Y. Hawang, J.-G. Park, H.-J. Noh, J.-Y.
extremely dilute conditions, it is difficult to apply the Kim, J.-H. Park, N.-M. Hwang, T. Hypon, Nat. Mat.,
prepared nanoparticles for new material and compos- 3, 891–895 (2005).
ite except expensive products such as quantum dot.
Recently, new preparation processes [12, 13],
where the complex of surfactant and metal ions were 3.2 Single nanoparticle motion in fluid
used for raw materials in aqueous and oil phase, have
been developed. Since nucleation and growth of 3.2.1 Single particle motion
nanoparticles occur from the complex and it does not
require the special nanopool structure such as reverse (1) Dynamic equation
micelle, it is possible to prepare dispersed nanoparti- The motion of a single particle is classified into two
cles with relatively high solid concentration. categories; one is a motion determined by the inertia,
Large-scale and low-cost synthesis method of the other is a random motion induced by the brown
nanoparticles is developing recently, however, the motion of fluid or medium. In this section, the deter-
aggregation, dispersion design and uniform packing ministic motion is described.
and arrangement of nanoparticles based on the sur- The motion of spherical particle having a diameter
face interaction control are at the initial stage for of D is described by the motion equation [1]
development. In this chapter, based on the above p
background, the basic theory, characterization and
control as well as analytical simulation method will dv ⎛ f v ⎞ du
2
r
D ⎜
be introduced to elucidate various aspects of nanopar- m p dt CA ⎝ 2 ⎠ ⎟ 6 f D 3 p dt
ticles including motion, surface structure and proper-
ties, interaction, dispersion/aggregation. ⎛ dv du⎞
3
f D p ⎜ ⎟ ⎟
12 ⎝ dt dt ⎠
References 3 t ⎛ dv du ⎞ d
D p 2 f ⎜ ∫ ⎟ F e (3.2.1)
[1] E. Verwey, J.Th.G. Overbeek: Theory of the Stability 2 ⎝ d d ⎠ t
0
of Lyophobic Colloids, Elsevier, Amsterdam,
Netherlands, (1948).
v, velocity vector of particle;
[2] L.V. Woodcock, Proceedings of a Workshop held at
u, velocity vector of fluid;
Zentrum für Interdisziplinäre Forschung University
v , relative velocity ( v u);
Bielefield, November 11–13, 1985, Edited by Th. r
, particle density;
p
Dorfmüller and G. Williams (Lect. Notes Phys., 277, , fluid density;
f
2
113–124 (1987)). A, project area of particle ( D /4).
p
[3] H. Kamiya, M. Mitsui, S. Miyazawa and H. Takano,
J. Am. Ceram. Soc., 83(2), 287–293 (2000). The first term on the right-hand side of equation (3.2.1)
[4] E. Garrone, V.B. Kaznsky, L.M. Kustov, J. Sauer, is the fluid resistance. The second term is the force
I.N. Senchenya and P. Ugliengo, J. Phys. Chem., 96, induced by the pressure gradient of fluid surrounding
1040–1045 (1992). the particle. The third term is the force for accelerating
the virtual added mass of the particles relative to the
[5] M. Iijima, M. Tsukada and H. Kamiya, J. Colloid
fluid. The fourth term is called as the Basset term. This
Interf. Sci., 301 (2), 418–424 (2007).
term describes the change of total fluid momentum
[6] H. Kamiya, H. Suzuki, D. Kato and G. Jimbo, J. Am.
due to the change of particle velocity during the time
Ceram. Soc., 76(1), 54–64 (1993).
0 to t [2]. The last term F is an external force.
e
[7] J. Karch, R. Birringer and H. Gleiter., Nature, 330, The second, third and fourth terms on the right-side
556–558 (1987). of equation (3.2.1) can be neglected, except for an
[8] M.A. Lopez-Quintela, Curr. Opin. Colloid Interf. Sci. extremely unsteady particle motion induced by
8, 137 (2003). extremely strong external force. In most cases of
119