The oldest, and most important, type of nanocomposite is that which has more or
less spherical nanoparticles. An example is the well-known “gold ruby glass,” which
consists of a glass matrix with gold nanoparticles as the second phase (see also
Section 9.5 and Figure 9.32). This material was first produced by the Assyrians in the
seventh century BC and reinvented by Kunkel in Leipzig in the seventeenth century.
It is interesting to note that the composition used by the Assyrians was virtually
identical to that used today. This well-known gold ruby glass needed a modification
of nanocomposites containing a second phase of spherical nanoparticles. In many
cases, as the matrix and the particles exhibit mutual solubility, a diffusion barrier is
required to stabilize the nanoparticles; such an arrangement is shown in Figure 2.5.
In the case of gold ruby glass, the diffusion barrier consists of tin oxide. In colloid
chemistry, this principle of stabilization is often referred to as a “colloid stabilizer.”
A typical electron micrograph of a near-ideal nanocomposite, a distribution of
zirconia nanoparticles within an alumina matrix, is shown in Figure 2.6. Here, the
Figure 2.5 Advanced zero-dimensional nanocomposite. Here, a diffusion barrier surrounds each
particle. This type of material is required if the nanoparticle and matrix are mutually soluble.
Figure 2.6 Transmission electron micrograph
of a zero-dimensional nanocomposite, showing
composite zirconia particles embedded in an
alumina matrix. The specimen was produced
from zirconia particles coated with alumina.
The image was taken from an ion beam-thinned
sample. There is a high probability that these
particles do not touch each other as they are in
different planes [3]. (Reproduced by permission
of Springer).
8j 2 Nanomaterials and Nanocomposites
less spherical nanoparticles. An example is the well-known “gold ruby glass,” which
consists of a glass matrix with gold nanoparticles as the second phase (see also
Section 9.5 and Figure 9.32). This material was first produced by the Assyrians in the
seventh century BC and reinvented by Kunkel in Leipzig in the seventeenth century.
It is interesting to note that the composition used by the Assyrians was virtually
identical to that used today. This well-known gold ruby glass needed a modification
of nanocomposites containing a second phase of spherical nanoparticles. In many
cases, as the matrix and the particles exhibit mutual solubility, a diffusion barrier is
required to stabilize the nanoparticles; such an arrangement is shown in Figure 2.5.
In the case of gold ruby glass, the diffusion barrier consists of tin oxide. In colloid
chemistry, this principle of stabilization is often referred to as a “colloid stabilizer.”
A typical electron micrograph of a near-ideal nanocomposite, a distribution of
zirconia nanoparticles within an alumina matrix, is shown in Figure 2.6. Here, the
Figure 2.5 Advanced zero-dimensional nanocomposite. Here, a diffusion barrier surrounds each
particle. This type of material is required if the nanoparticle and matrix are mutually soluble.
Figure 2.6 Transmission electron micrograph
of a zero-dimensional nanocomposite, showing
composite zirconia particles embedded in an
alumina matrix. The specimen was produced
from zirconia particles coated with alumina.
The image was taken from an ion beam-thinned
sample. There is a high probability that these
particles do not touch each other as they are in
different planes [3]. (Reproduced by permission
of Springer).
8j 2 Nanomaterials and Nanocomposites