Metallic and Ionic Nanoparticles Extendable Structures: Melting Point, Color, Conductivity.

Metallic and Ionic Nanoparticles

Extendable Structures: Melting Point, Color, Conductivity

Extendable Structures: Melting Point, Color, Conductivity© McREL 2009

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Why is the cleansing ability estimate such a wide range?

How many grams of iron powder would it take to present a surface area equal to that of 1 gram of nanoparticles? ______

_____ liters of water can be cleaned by one gram of iron nanoparticles.

How would iron nanoparticles affect the rate of TCE cleanup?

Iron Nanoparticles


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http://www.phschool.com/science/science_news/articles/special_treatment.html

Iron Nanoparticles in Your Backyard


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Date of Test

12/01/02 1/06/03 2/03/03

Distance from Injection Well 1

TCE Concentration

ppb

pH TCEConcentration

ppb

pH TCE Concentration

ppb

pH

8 ft (2.4 m)

41,000 6.92 100 7.87 160 8.51

10 ft (3.6 m)

5,100 6.77 47 8.18 79 8.61

20 ft (7.1 m)

7,400 6.91 690 7.08 610 7.17

Distance from Injection Well 2

0 ft (0 m)

88,000 7.32 11 8.24 78 8.27

6 ft (1.8 m)

76,000 6.9 420 8.52 730 7.91

Iron Nanoparticles in Your Backyard


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Philosophical Chairs


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What physical properties are affected by the size of the nanoparticles?

Physical Properties


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Nanoparticles


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What do these graphs tell us?

Metallic Nanoparticles


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Gold Nanoparticles


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5 nm diameter gold nanoparticles

The image represents nanoparticles in suspension.

All of them are the same size. Those that appear smaller are further away. The image represents nanoparticles in suspension.

All of them are the same size. Those that appear smaller are further away.

Gold Nanoparticles


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Adapted from F. G. Shi, J. Mater. Res., 1994, 9(5), 1307-1313,reproduced in Nanoscale Materials in Chemistry, edited by Kenneth J. Klabunde, 2001, John Wiley & Sons, Inc, New York, NYAdapted from F. G. Shi, J. Mater. Res., 1994, 9(5), 1307-1313,reproduced in Nanoscale Materials in Chemistry, edited by Kenneth J. Klabunde, 2001, John Wiley & Sons, Inc, New York, NY

Ionic Nanoparticles


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Increased rates of some chemical reactions

Decreased melting points

Increased surface area to volume ratios of nanoparticles

Metallic and Ionic Nanoparticles


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Bulk Gold Nano Gold

2-3 mm diametergold beads in toluene

4-5 nm diameter gold nanoparticles in toluene

Courtesy of Kansas State University

Gold Particles


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All colors of light are reflected from a

smooth silver surface

Some blue light is absorbed by a smooth

gold surface

Metallic Macroparticles


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As the size of the nanoparticles decrease and

shapes change to include more edge and corner sites,

the ENERGY and MOTION of valence electrons change.



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light interacts with surface electrons

electrons move in unison, forming waves

electron waves behave as if they were a single, charged particle, interacting with only specific wavelengths of light

At the nano level



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As particle size decreases, electromagnetic radiation interacts with free electrons to absorb, reflect, or transmit different colors of light.

Color transmitted through stained glass windows

Gold

Silver

Color of lustrousmacro samples

Larger Smaller



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“sea of electrons”

s, p, d, and f atomic orbitals

random motion

electrons can be elevated to higher energy levels

Electrons in Atomic Orbitals

Electrons in Metals


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As particle size decreases, conductivity decreases



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How and why do the chemical and physical properties

of nanosamples differ from those of macrosamples

of the same substance?

Extendable Nanoparticles


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1. Name three physical properties that are affected by surface energy?

2. How were the physical properties affected by surface energy?

3. What do you think is the difference between extendable and discrete nanoparticles?

Making Connections


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Lesson 1.2 What Makes Nanoscience so Different?

What makes Nanoscience so different?Compare Newtonian and Quantum Chemistry Regimes as they relate to nanoscale science

Lesson 1.3 What Makes Nanoscience so Important?

Interdisciplinary science The development of new technologies and instrumentation applications whose risk and benefits have yet to be determined

Lesson 3.1Carbon Chemistry

Lesson 1.1 What is Nanoscience?

What is Nanoscience? Examine and Compare size: macro, micro, sub-micro (nano)SI prefixes

Lesson 2.2 Extendable Solids: Reactivity, Catalysis, Adsorption

The difference between the energy at the surface atoms and energy of the interior atoms results in increased surface energy at the nanoscale

Higher surface energy allowing for increased reactivity, adsorption and catalysis at the nanoscale

Lesson 2.3Extendable Structures: Melting Point, Color Conductivity

In Extendable Structures:Melting point decreases because surface energy increases

Color changes because electron orbital changes with decreased particle size

Electrical conductivity decreases because electron orbital changes with decreased particle size

Lesson 3.2Fullerenes and Nanotubes

Lesson 2.1 Extendable Solids

As the size of the sample decreases the ratio of surface particles to interior particles increases in ionic and metallic solids

Poster Assessment

Students will further investigate the essential question that they have considered throughout the module: How and why do the chemical and physical properties of nanosamples differ from those of macrosamples?

Module Flow Chart

Metallic and Ionic Nanoparticles Extendable Structures: Melting Point, Color, Conductivity.

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Transcript of Metallic and Ionic Nanoparticles Extendable Structures: Melting Point, Color, Conductivity.