Experiment 3
Synthesis of Silver Nanoprisms with Variable
Size and Investigation of their Optical
Properties
WINTER 2021
, Abstract
The purpose of this experiment is to determine the size of silver nano-prisms originating from
the theory that when materials change their size drastically to a nano scale, they act different
from the bulk materials due to the dependency on the electron behavior and thus their properties,
physical and chemical, change. Further investigation involves in determining the change of
optical properties. With the different volume of KBr solution adding (it affects the size of the
silver nano prisms), the color of silver solutions will show different color, after they are
illuminated by ultraviolet light. Then, using UV-Vis Spectrophotometer to get the volume of the
absorbance.
Theory
Quantum size effect describes the physics of electron properties in solids with great reductions in
particle size. This impact doesn't become possibly the most important factor by going from full
scale to miniature measurements. Notwithstanding, it becomes predominant when the nanometer
size range is reached. Materials can be produced that are nanoscale in one dimension (for
example, very thin surface coatings), in two dimensions (for example, nanowires and nanotubes)
or in all three dimensions (for example, nanoparticles and quantum dots).[2]
One of the most direct effects of reducing the size of materials to the nanometer range is the
appearance of quantization effects due to the confinement of the movement of electrons.[1]
Actual properties of nanoscale materials contrast from that of mass materials because of the
mathematically confined electrons on nanoparticles bringing about quantum size impacts.
Surface Plasmon Resonance is a phenomenon that occurs when polarized light hits a metal film
at the interface of media with different refractive indices.[3]
When the light is absorbed by the surface, it generates an electron cloud. When this electron
group of the nanoparticle associates with light it results in surface plasmon resonance, this is the
result of quantum size effect.
This experiment helps determine the effect of nanoparticle size on the surface plasmon band.
In order to synthesize silver nano-prisms, sodium borohydride was used to reduce silver nitrate
and initiate nano-prism formation.
NaBH4 (aq) + 8AgNO3 (aq) + 4H2O (l) → Na [B(OH)4] (aq) + 8Ag (s) + 8HNO3 (aq)
Synthesis of Silver Nanoprisms with Variable
Size and Investigation of their Optical
Properties
WINTER 2021
, Abstract
The purpose of this experiment is to determine the size of silver nano-prisms originating from
the theory that when materials change their size drastically to a nano scale, they act different
from the bulk materials due to the dependency on the electron behavior and thus their properties,
physical and chemical, change. Further investigation involves in determining the change of
optical properties. With the different volume of KBr solution adding (it affects the size of the
silver nano prisms), the color of silver solutions will show different color, after they are
illuminated by ultraviolet light. Then, using UV-Vis Spectrophotometer to get the volume of the
absorbance.
Theory
Quantum size effect describes the physics of electron properties in solids with great reductions in
particle size. This impact doesn't become possibly the most important factor by going from full
scale to miniature measurements. Notwithstanding, it becomes predominant when the nanometer
size range is reached. Materials can be produced that are nanoscale in one dimension (for
example, very thin surface coatings), in two dimensions (for example, nanowires and nanotubes)
or in all three dimensions (for example, nanoparticles and quantum dots).[2]
One of the most direct effects of reducing the size of materials to the nanometer range is the
appearance of quantization effects due to the confinement of the movement of electrons.[1]
Actual properties of nanoscale materials contrast from that of mass materials because of the
mathematically confined electrons on nanoparticles bringing about quantum size impacts.
Surface Plasmon Resonance is a phenomenon that occurs when polarized light hits a metal film
at the interface of media with different refractive indices.[3]
When the light is absorbed by the surface, it generates an electron cloud. When this electron
group of the nanoparticle associates with light it results in surface plasmon resonance, this is the
result of quantum size effect.
This experiment helps determine the effect of nanoparticle size on the surface plasmon band.
In order to synthesize silver nano-prisms, sodium borohydride was used to reduce silver nitrate
and initiate nano-prism formation.
NaBH4 (aq) + 8AgNO3 (aq) + 4H2O (l) → Na [B(OH)4] (aq) + 8Ag (s) + 8HNO3 (aq)
