Alabama Center for Nanostructured Materials (ACNM)

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Alabama Center for Nanostructured
Materials (ACNM)


Mahesh V. Hosur, PI/Director

Center for Advanced Materials

Tuskegee University

Tuskegee, AL 36088

Annual EPSCoR Meeting, Feb. 13, 2007, Huntsville, AL

ACNM Mission/Goals


Synthesize

and

produce

bulk

nanocrystalline

materials

and

develop

new

materials

with

enhanced

thermal,

physical

and

mechanical

properties



Integrate

research

and

education

in

the

area

of

Nanotechnology


Initiate

new,

as

well

as

enhance

existing

partnerships

with

industry

and

academia

to

attract

new

funding

through

development

of

joint

proposals


Educate

and

graduate

underrepresented

students

with

expertise

in

the

area

of

Nanotechnology


Conduct

National

and

regional

workshops,

summer

high

school

and

undergraduate

student

internship

programs


Research, Education, Training and Outreach

Personnel

University

Faculty

Grad.
Students

Undergrad.
Students

High School
Students

Tuskegee

5

18

8

8

Alabama A& M

8

4

5

-

Auburn

1

1

-

-

UAH

3

5

1

-

USA

1

1

1

-

18

29

15

8

Out of 29 graduate students, 15 are PhD students with 8 of them being
African
-
Americans, 5PhD students are being supported by the alabama
State Graduate Student Research Program

It is anticipated that at least 5 PhD students will graduate by May 2008

GSRP Awardees


Ivy K. Jones Wanda D. Jones Merlin Theodore


Jean Michael Taguenang


Bopah Chhay

ACNM Outcomes


Journal/conference Publications: 64


Presentations at the national and international conferences


Organizing and chairing sessions at international conferences


M.S. Thesis (5), Undergraduate technical reports


Summer high school program


Graduate courses in Nanotechnology at TU and USA


Participation of students in oral and poster presentation
competitions


Increased number of proposals submitted and funded


Publicity


Visit to the center by President Bush, April 19, 2006


First article of TU EPSCoR program appeared in Montgomery
advertiser on July 25, 2005:
http://www.montgomeryadvertiser.com/NEWSV5/storyV5tuske
gee25w.htm


President Bush Visits Tuskegee University

Center for Advanced Materials (T
-
CAM)
-
April 19, 2006


“I met some students who knew lot about nanotechnology
-
PhD candidates who knew
lot about nanotechnology”
-

President Bush, April 19, 2006

Summer High School Program

Eric Rousell, Jr.

Selma Early College High School (10th grade)

Future Career: Aerospace or Marine
Engineering


While in this program, I learned about
Material Science and Engineering. We also
learned about nanotechnology and how it is
being applied in numerous applications in our
everyday lives. I learned a lot and would like
to come back next year.
-----
Eric Rousell, Jr.

Summer 2006 High School Students
with their mentors

Collaborations

National/Federal Labs: Oak Ridge National Laboratory,
National High Magnetic Filed Laboratory, ARL, AFRL,
Navy, NRL, ORNL, NASA
-
MSFC


Academia: Cornell, Purdue, Univ. of Delaware, Mississippi
State University, Carnegie Mellon Univ., University of
Alabama, Tuscaloosa, Florida State University


Industry: Raytheon, Boeing, IBM, USP


International: Japanese National Institute for Metals,
University of Liverpool

Course Development

Nanocomposite Materials (Dr. Rangari, TU with Dr.
Anter from FSU, 10 students)


Nanoscale material synthesis, properties and applications


Theory, modeling and simulation studies


Synthesis mechanisms and morphological changes in nanoscale
materials systems, as well as the properties of materials at the
nanoscale

Nanocomposites (Dr. Parker, USA, 16 students)


Dielectric, electric, magnetic, optical and mechanical properties of
nanocomposites


Research and analyze published work dealing with
applications


Research Themes


Synthesis,

Processing,

Modeling,

Characterization

of

nanophased

fibers,

matrices,

composites,

and

sandwich

constructions

(Tuskegee)


Nano
-
layered

nanoparticles,

Glassy

Polymeric

Composites

(Alabama

A

&

M,

Tuskegee)


Molecular

Dynamic

simulations

(Auburn)


Modeling

and

processing

of

nanoparticles

under

the

influence

of

magnetic

field

(Univ
.

of

South

Alabama,

Tuskegee)


LC

Based

Chemical

and

Biological

Sensor

Using

Capacitive

Transduction,

Integrated

Nanophotonics,

LC

Polar

Anchoring

Measurements

(Univ
.

of

Alabama,

Huntsville)

Thermal and Mechanical Properties of CNF/
Epoxy Nanocomposite

Matrix: SC
-
15 Epoxy

Reinforcement: Carbon Nano Fiber

0 wt. %, 1 wt. %, 2 wt. % and 3 wt. %

Storage

Modulus


70
%

improvement

Glass Transition Temp.


7
o
C

increase


Tensile Modulus


17.4%

improvement


Tensile Strength


19.4%

improvement


0
4
0
8
0
1
2
0
1
6
0
2
0
0
T
e
m
p
e
r
a
t
u
r
e

(


C
)
0
4
0
0
8
0
0
1
2
0
0
1
6
0
0
2
0
0
0
S
t
o
r
a
g
e

M
o
d
u
l
u
s

(
M
P
a
)
o
N
e
a
t

E
p
o
x
y
1

w
t
.

%

C
N
F
2

w
t
.

%

C
N
F
3

w
t
.

%

C
N
F
0
.
0
0
0
.
0
1
0
.
0
2
0
.
0
3
0
.
0
4
S
t
r
a
i
n
0
2
0
4
0
6
0
8
0
S
t
r
e
s
s

(
M
P
a
)
N
e
a
t

E
p
o
x
y
1

w
t
.

%

C
N
F
/
E
p
o
x
y
2

w
t
%

C
N
F
/
E
p
o
x
y
3

w
t
.

%

C
N
F
/
E
p
o
x
y
1
0
0
1
0
0
0
1
0
0
0
0
1
0
0
0
0
0
1
0
0
0
0
0
0
N
u
m
b
e
r

o
f

C
y
c
l
e
s
3
5
4
0
4
5
S
t
r
e
s
s

(
M
P
a
)
N
e
a
t

E
p
o
x
y
1
w
t
.
%

C
N
F
/
E
p
o
x
y
2
w
t
.
%

C
N
F
/
E
p
o
x
y
3
w
t
.
%

C
N
F
/
E
p
o
x
y
0
.
0
0
0
.
2
0
0
.
4
0
0
.
6
0
D
i
s
p
l
a
c
e
m
e
n
t

(
m
m
)
0
2
0
0
4
0
0
6
0
0
8
0
0
1
0
0
0
L
o
a
d

(
N
)
3
%

C
N
F
/
E
p
o
x
y
2
%

C
N
F
/
E
p
o
x
y
1
%

C
N
F
/
E
p
o
x
y
N
e
a
t

E
p
o
x
y
Fracture toughness


23% increase in fracture toughness


was observed in 2 wt% system

Fatigue

Performance

At the same fatigue stress level,

140% improvement

in fatigue life

was observed in 2 wt% system by
the bridging effect of CNF

Mechanical Properties of
Nanophased Nylon Fibers

0
5
10
15
20
25
0
200
400
600
800
Strai n in %
stress in MPa
With the use of 1% silica spherical
nanoparticles by weight,
an increase of
100 to 150%

in the tensile properties

was observed in nylon
-
6.

It was also observed that the fibers
infused with 1% by weight whisker form of
Si
3
N
4
exhibited
more than 300%
improvement in tensile strength
.

TEM picture of Nylon
-
Si
3
N
4

Aligned

Nano whisker

Experimental
-
Flexural Results

VARTM results


Hand
-
Layup results

Flexural stress
-
strain plot

Flexural
Strength,
MPa

% Gain/
Loss in
strength

Flexural
Modulus, GPa

% Gain/
Loss in
modulus

Neat

380
±

3. 3

-

37.57
±

0.77

-

1% Nanoclay


426
±

10.81

12.10

43.8
±

2. 13

16.58

2% Nanoclay

498
±

12. 81

31.05

46.2
±

0. 81

22.97

3% Nanoclay

446
±

8. 95

17.36

46.9
±

1. 22

24.8

0
1
0
0
2
0
0
3
0
0
4
0
0
5
0
0
0
0
.
0
0
3
0
.
0
0
6
0
.
0
0
9
0
.
0
1
2
1
%
n
a
n
o
c
l
a
y
2
%
n
a
n
o
c
l
a
y
3
%
n
a
n
o
c
l
a
y
N
e
a
t

c
o
m
p
o
s
i
t
e
S
t
r
a
i
n
,

m
/
m
F
l
e
x
u
r
a
l

s
t
r
e
s
s
,

M
P
a
Fabric: 8
-
layered plain weave
3k, Resin: SC
-
15 Epoxy,
Nanoclay: Nanocor
®

I
-
28E

Impact Response

VARTM results

Fabric: 8
-
layered plain weave 3k, Resin: SC
-
15 Epoxy, Nanoclay: Nanocor
®

I
-
28E


Neat 1%


2% 3%

Impact Energy: 30J

Sample Damage Area (mm
2
)

Neat 1144

1% 860

2% 660

3%



920

Different Methods of Functionalization




Oxidation








Fluorination









Amino
-
functionalization



HNO
3
/H
2
SO
4

F F F


F F F


C

O

OH

OH


C

O


NH
2


Flexural 3
-
point bend test

Material

Max. Strength

(MPa)

Modulus

(GPa)

Epon 862 neat

139.7
±

7.1

3.5
±

0.08

Nanocomposite/ MWCNT
-
UNMOD

152.1
±

20.2

4.1
±

0.2

Nanocomposite/ MWCNT
-
COOH

151.1
±

14.9

4.8
±

0.6

Nanocomposite/ MWCNT
-
F

136.1
±

12.2

3.6
±

0.0

Nanocomposite/MWCNT
-
NH
2

162.8
±

4.6

4.2
±

0.1


Conventional polymer foams

are produced, for example, by introducing gas
bubbles into liquid monomer



Syntactic Foams

are produced by embedding pre
-
formed hollow/solid
microspheres within a polymer matrix

PVC Foam (open cell)

PUR Foam (closed cell)

PVC Foam (closed cell)

Syntactic Foam



Microballoons act as cells of the conventional foam



They are very similar to the cellular, gas expanded solidified liquid



A tertiary system whereas conventional foams are binary system

Syntactic Foam (TU)

Matrix

SC
-
15 Epoxy

Part A: diglycidylether of bisphenol
-

A,

Part B: Diethelene tri amine (DETA)

Viscosity: 300 cps, Density: 1.09 g/cc

Microballons

K
-
15 (3M)

Size: 30
-
105
µ
m

Avg. Density: 0.15 g/cc

Avg. wall thickness: 0.7
µ
m

Nanoparticles

Nanoclay
-

K10 (Sigma Aldrich Inc.)

Shape: Plate type

Avg. surface area: 220
-
270 m
2
/g

Manufacturing of Nanophased Syntactic

Foam (TU)

0
1
0
2
0
3
0
0
0
.
5
1
.
0
1
.
5
2
.
0
N
e
a
t

s
a
m
p
l
e
1

w
t
%

N
a
n
o
c
l
a
y
2

w
t
%

N
a
n
o
c
l
a
y
3

w
t
%

N
a
n
o
c
l
a
y
S
t
r
a
i
n
,

%
S
t
r
e
s
s
,

M
P
a
Flexural
strength
(MPa)

Improvement
in strength
(%)

Flexural
modulus
(GPa)

Improvement
in modulus (%)

Neat
sample

17.7
±
0.21

-

1.33
±
0.039

-

1 wt%
Nanoclay

20.3
±
0.13

14.7

1.50
±
0.036

12.8

2 wt%
Nanoclay

25.1
±
0.15

41.8

1.57
±
0.043

18.0

3 wt%
Nanoclay

22.8
±
0.11

28.8

1.57
±
0.035

18.0

Mechanical Properties of Syntactic

Foam (TU)


Flexural test results of the samples indicate a maximum
improvement in strength and modulus of about 42%
and 18% respectively for 2 wt % nanoclay system

0
500
1000
1500
2000
Storage Modulus (MPa)
20
40
60
80
100
120
140
160
Temperature (°C)
–––––– Neat sample
– – – 1 wt% nanoclay
–––– · 2 wt% nanoclay
–– – – 3 wt% nanoclay
Universal V3.8B TA Instruments
0.0
0.1
0.2
0.3
0.4
Tan Delta
20
40
60
80
100
120
140
160
Temperature (°C)
–––––– Neat sample
– – – 1 wt% nanoclay
–––– · 2 wt% nanoclay
–– – – 3 wt% nanoclay
Universal V3.8B TA Instruments
Thermal Properties of Syntactic Foam (TU)


Storage modulus


(MPa)

% Change

Loss modulus
(MPa)

% Change

T
g

(
0
C)

Change
(
0
C)

Neat sample

1220
±
12

-

123.2
±
0.23

-

105
±
0.32

-

1 wt% Nanoclay

1497
±
26

22.7

145.6
±
0.41

18.2

109
±
0.43

4

2 wt% Nanoclay

1590
±
21

30.3

157.4
±
0.82

27.8

112
±
0.19

7

3 wt% Nanoclay

1292
±
18

5.9

128.8
±
0.11

4.5

109
±
0.22

4

Storage modulus increased by 30% and also 7
0
C increase in glass transition
temperature is observed for 2 wt % nanoclay system

Thermal Properties of Syntactic Foam (TU)


-20
0
20
40
60
80
Dimension Change (µm)
20
40
60
80
100
120
140
160
180
Temperature (°C)
–––––– Neat sample
– – – 1 wt% nanoclay
–––– · 2 wt% nanoclay
–– – – 3 wt% nanoclay
Universal V3.8B TA Instruments
Coefficient of thermal expansion was found
using the formula as follows:






The slope of the initial portion of the curves
give the value for dL/dT and L is the
thicknesses of the samples

CTE (
µ
m/m
0
C)

Change

(
0
C)

Neat sample

41.9
±

0.62

-

1 wt% Nanoclay

40.5
±

0.33

-
1.4

2 wt% Nanoclay

39.7
±

0.93

-
2.2

3 wt% Nanoclay

35.1
±

0.39

-
6.8

dT
dL
L
*
1


TMA results exhibited 70C decrease in
CTE value for 3 wt % nanoclay system









Objectives

Traditional Technology

BiTe/SbTe Semiconductors

21st Century Technology
---
Metal/Insulator




nano superlattice

Results






Higher Thermoelectric figure of merit

Approach



Zn
4
Sb
3

/ CeFe
(4
-
x)
Co
x
Sb
12

nano
-
layered superlattices



Si
1
-
x
Ge
x
/Si after

Bombardment by 5 MeV Si Ions


Au/SiO
2

Metal nano particle superlattice


Future Plans


Produce a prototype high temperature


metal/insulator thermoelectric generator


for direct energy conversion of waste heat



Thermoelectric Generator

(with superlattice nano particles): AAMU

Summary



50 to 1000 nanolayers were
produced in house.



Post Irradiation reduced thermal
conductivity, increased electrical
conductivity as well as increase
Seebeck Coefficient.



Thus Figure of Merit increased.

ZT=(S
2
σ
T)/



Figure of Merit (ZT)







+V

2



-

V



xB



+V

1



Neutral Return



Mass Selector



Pump



Acceleration

and focusing



Electric arc nano

Particle Source

Nano particle production and electro
magnetic mass separation:
AAMU

Approach

1 Produce 10
-
100 nm metal particles

2 Use ion beam techniques


for mass separation

3 Use optical techniques


to characterize size distribution

Future Plans



Continue student involvement in nano
scale technology research


(Nano particles for innovative solar
cells)


Work with Tuskegee University for tests
of carbon composites with nano
particle additives


Objective


Involve
undergraduate students


in significant nano technology


Results










Optical evidence of 2
-
5 nm

silver nano particle production

300
400
500
600
700
0.0
0.2
0.4
0.6
43.5 nm
03 November 2006
Test009 and 010 Cary 5000


Optical absorption spectrum of silver nanoparticles on glass
(Obtained by electric arc in normal atmosphere)
Sample 2
Sample 2 immersed in H
2
O
-Log ( 1/T )
Wavelength (nm)




Approach

1 CNT: Electrical and Mechanical

2 Al
2
O
3

and SiC, Electrical

3 Ion Beam Surface Modification


Controlled cell adhesion


Controlled porosity

Collaborate closely with carbon

composite pioneers at Tuskegee University

Objectives


To Enhance

1 Mechanical properties: Hardness, Stiffness, Strain to
fracture

2 Transport properties: Electrical, Thermal, Fluid diffusion

3 Biocompatibility

Future

Plans

Technology

Transfer

Aerospace

Medical

Consumer

Carbon Nano Tube

50
m
m

10
-
30 nm

Glassy Polymeric Carbon Composites

AAMU




0.00
0.05
0.10
0.15
0.20
0.25
0
5
10
15
20
25
30
35
40
45
50
55


Pure GPC
GPC/CNT 1 wt%
GPC/CNT 2 wt%
GPC/CNT 3 wt%
GPC/CNT 5 wt%
GPC/CNT 10 wt%
Stress (MPa)
Strain (%)
10%


5%

3%


2%

1%


Virgin

GPC CNT

Composite




Results

50%

Increased
strain to failure

300%

Increased
stiffness

High Temperature (3000
°
C), Low Density (1.45 /cm
3
)

Thermal expansion (zero), Inert (except oxygen)

Magnetic Field
-
Induced Nanoparticle
Dispersion (USA)


Good

dispersion

of

heavy

metallic

nanoparticles

(iron

oxide)

under

magnetic

field


Development

of

lab

scale

magnetic

field

device


Modeling

magnetic

field

dependence

of

nanoparticle

dispersion


Good

agreement

between

experimental

results

10
1
10
2
10
-1
10
0
10
1
10
2
Flocculation Rate vs. Magnetic Field Density
Vma
1/2
Flocculation Rate
Capture

efficiency

versus

(root)

magnetic

velocity

for

various

thicknesses

of

the

surfactant

layer

indicating

the

extent

to

which

the

surfactant

layer

thickness

frustrates

the

process

of

agglomeration

Capture Efficiency Vs Magnetic Velocity
for different surfactant layer thicknesses

Summary of Research Activities of
Auburn ACNM Team

(a)

(b)

Ab initio calculated (a) lattice thermal expansion and (b) elastic constants of Al
2
O
3
.



Study thermal and mechanical properties through molecular modeling and simulation



Model structure and properties of hard ceramic fillers and soft polymer matrix



Modeling of Si
3
N
4
, Al
2
O
3
, SiC, and TiO
2



Initiated simulation studies using LAMMPS code developed by Sandia National Lab.

Perfluorocyclobutyl (PFCB) optical waveguides with air trenches
(partial support for 2 PhD students)

Ring Resonator Design with
Air Trench Splitters

Measurement of AWG in
PFCB

ACNM
-
UAH Effort




Nanofabrication of air trenches in PFCB waveguides enables high efficient,
extremely compact planar optical components


Fabricated smallest arrayed waveguide (AWG) utilizing nano
-
patterned air
trench reflector


Fabricated a compact ring resonator utilizing nano
-
patterned air trench
splitters



Integrated Nanophotonics

Nanophotonic wave structure significantly reduces waveguide loss

New waveguide allows meter propagation distance propagation rather than mm

Proposal Submission

Funded Grants: ($3.985 M)


A Research and Educational Partnership in Nanomaterials between Tuskegee University and
Cornell University, 8/1/06
-
7/31/11,
($2.55 M with $2.1 M TU share)


Enhancement of Research Infrastructure in the Materials Science and Engineering Program
at Tuskegee University,
9/1/06
-
8/31/08,
($1.0 M)


Characterizations of Nanocomposites and Composite Laminates, Air Force/HBCU/MI
program
8/1/05
-
7/31/07 ($225 K, subcontract from Clarkson Aerospace, Inc.)


Modeling High
-
rate Material Responses for Impact Applications,
11/1/05
-
10/31/06
(subcontract from Mississippi State Univ. $100K)


SBIR Phase I: Advanced Composites Research to Reduce Costs, 6/15/2006,
Ondax Inc.

($105K)



STTR Phase I: Nanocluster characterization in Volume Holographic Glass
gratings,6/25/2006,
Ondax Inc. ($105K)


Other non funded proposals



$ 881 K (TU being prime)


$ 18.35 M (with Mississippi State and Florida Atlantic with TU share of $2.05 M)