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7/27/2019 Lab Projects Listr

1/25

Experiments

Synthesis of Nano Particles and

Encapsulation

Synthesis of Hexagonal Mesoporous

Silica & Carbon

Synthesis of Organic and Carbon

Xerogels

Synthesis of Silver NanoWires


2/25

Demostration Experiments

Sol-Gel Synthesis via TMOS

Sol-Gel Synthysis using Sodium silicate

better known as furnace cement.

Ultrasonic synthesis of TMOS


3/25

SOL-GEL SCIENCE

Gelification

Aging

Soaking

Mix the reactives

Sol

Gel

Gel Aerogel

Hydrolysis and Condesation

reactions take place

Gelification

Aging Drying


4/25

Gelification

Mix reactives

Sol

Gel

Gel

Gelification

Aging

SiOR

OR

OR

OR

OH2+ ROH+SiOH

OROR

OR

+ + ROHSiOR

OROR

OR

SiO

Si

OR OR

OR OR

OR OR

SiOH

OROR

OR

+ OH2SiOR

OR

OH

OR

SiOH

OR

OR

OR

+ SiO

Si

OR OR

OR OR

OR OR

Hydrolysis and Condesation

reactions take place


5/25

Designing Nanomaterials

First Step

Silica Solution

Precursor: Tetraetilortosilicate

Si(OCH2CH3)4Solvent: Ethanol

Catalyst: OxalicAcid

ModificationspH (final product)Temperature (crystal phase)Precursor (Type of material)

Time (Strength)

etc


6/25

(I) SOL-GEL SYNTHESIS OF AEROGELS

Aerogels are a unique, nanostrutured material derived from gels. Gels are a novel class

of material exhibiting solid-like behavior although consisting predominantly of a liquid phase.Their solidity derives from a continuous interpenetrating framework that, in essence, acts like a

molecular scaffold extending throughout the liquid. This perspective of a gel as a molecular

web in a liquid has found many industrial applications.

Figure 1: A silicon oxide low density aerogel


7/25


8/25

Synthesis of Nano Particles and

Encapsulation Synthsis of Tiatnium and silica

nanoparticles

Sol-Gel Encapsulation

Jorge Arias


9/25


10/25

Encapsulated Dendrimer

The following figure shows mono dispersed

Starburst PAMAM polyamidoamine dendrimersencapsulated in a sol-gel matrix of silica at 25 wt.

%. Surface area analysis shows the material

surface area was 617 m2/g. The dark spheres in

Figure 1 dispersed throughout the silica matrixshow diameters similar to their hydrodynamic

values for this dendrimer in solution.


11/25

PAMMA Dendrimer


12/25

Sol-Gel Encapsulated Dendrimer


13/25


14/25

Synthesis of Hexagonal

Mesoporous Silica & Carbon

This lab couples the hydrolysis andcondensation of TEOS or other silica

sources with Structure directing agents suchas surfactants or polymers .

It also uses the final silica mesoporousmaterial as a template to synthesize a high

surface area, hexagonal pure carbonmaterial.

Phong Nugyen, instructor


15/25

The uniqueness of surfactant templated materials allows a variety of metal oxides to be

formed with uniform honeycomb structure and surface area approaching 1000 m2/g.

Surfactant templated materials have already been synthesized by the authors Thesematerials were synthesized with Mg, Cr, Ru, Pt, and Co doped in the MCM-41 silica

oxide.

MESOPOROUS ZEOLITE-TYPE MATERIALS

FIGURE 7. TEM of MCM-41 synthesized by the author


16/25

FIGURE 8: TEM of mesoporous silica with different average poressizes

Synthesis of large Scale Mesoporous Substrates

(A) 60, (B) 89 , (C) 200 , (D)260 .


17/25


18/25


19/25

Synthesis of Organic and

Carbon Xerogels Resorcinol is a molecule that much like TEOS can

undergo hydrolysis and condensation reaction to

form a gel structure that can be dry as a xerogel oraerogel.

This gel can be further transformed in to a high

surface area carbon material. It gives the highest

capacitance per unit volume .

Laurent Moch will demonstrate.


20/25


Particles are templated into a cylindrical

shape using a polymer.

Martina Dreyer.


21/25



22/25

Figure 5: Anodized Alunminum

NANOSTRUCTURED ANODIZED ALUMINUM

Anodized aluminum is an ideal substrate in that it possesses verticalpores perpendicular to its surface.These nanopores are formed byelectrochemical etching and pore diameter can be precisely controlledfrom 300 nm down to 2nm.


23/25

Figure 6: Diagram for using anodized aluminum to synthesize carbon nanotubes


24/25

FIGURE 4: Nanotube Reactor for CVD Synthesis of Carbon Nanobes in Our

Laboratory

Reactors CVD Synthesis of SWNTs

Two parallel thermal reactors capable have already been constructed and tested,

These carbon nanotube reactors can operate from 100 torr to above atmosphericThe reactors temperature is computer controlled and may be ramped.

The reactors are set up to run either in parallel or separately

One of the reactors can handle large substrates such as silicon wafers up to 6

inches.


25/25

(II) CARBON NANOTUBES

Below is pictured a diagram of the unique geometry of a carbon nanotube as well as a transmission electronmicrograph of a single wall nanotube produced in our department.

FIGURE 2: Open Nanotube (Newman)

At 100-150 times the strength of steel yet only 1/60th of its weight, nanotubes are being recognized as thepenultimate fiber with a promise for material technology far surpassing all previous fibers yet created. This promise,as noted, is far beyond just the properties obtained with carbon fibers, now used in the highest performancecomposites. Potentially, future airplanes formed from

CARBON NANOTUBE TEM OF NANOTUBE

FIGURE 3: Nanostructure and TEM of single wall nanotube as synthisized