Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Perform an audio check by going to
Tools > Audio > Audio Setup Wizard
The webinar will begin at 1pm Eastern Time
Electrospinning Polymer Fibers: A Simple Technique of Introducing Nanoscience to Undergraduates
May 15, 2014
Chat Box
Chat Box
Send Questions
and Message
Here
Begin Recording
The webinar will begin at 1pm Eastern Time
Electrospinning Polymer Fibers: A Simple Technique of Introducing Nanoscience to Undergraduates
May 15, 2014
Hosted by MATEC NetWorks www.matecnetworks.org
Brought to You By:
The NACK Network, established at the Pennsylvania State
College of Engineering, and funded in part by a grant from
the National Science Foundation (DUE 1205105).
Brought to you by:
Dr. Nicholas Pinto Professor in the Department of Physics and
Electronics at the University of Puerto Rico, Humacao
Campus.
• His research is in the field of conducting polymers
for use as gas sensors, devices and in organic
electronics at the nanoscale.
• He is also engaged in efforts to integrate
undergraduate research into the Senior Lab course
Moderator: Mike Lesiecki
MATEC
Today’s Presenter
Electrospinning polymer fibers: A simple technique of introducing nanoscience to undergraduates
Nicholas J. Pinto
Dept. of Physics and Electronics
University of Puerto Rico-Humacao
http://www.freeworldmaps.net/centralamerica/puertorico/location.html
Bonding p 2 eV
10 eV
En
erg
y
D.L. Smith, MRS Bull 29, 647 (2004).
Polyaniline Electronic structure
Conducting polymers/Metal oxides
Figure 1: Chemical structure of 4-polyethylenedioxythiophene (PEDOT)
doped with poly(styrene sulfonic acid) (PSS) PEDOT-PSS blend (Baytron P).
PSS
PEDOT
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
Figure 1: Chemical structure of 4-polyethylenedioxythiophene (PEDOT)
doped with poly(styrene sulfonic acid) (PSS) PEDOT-PSS blend (Baytron P).
PSS
PEDOT
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
Poly(3-hexylthiophene)
[P(ND12OD-T2)]n - ActivInkTM
SnO2
ZnO
Antibonding s
Antibonding p
Bonding p
Bonding s
Conductivity of Electronic Polymers
106
104
102
100
10-2
10-4
10-6
10-8
10-10
10-12
10-14
10-16
Ag, CuFeMg
In, Sn
Ge
Si
AgBr
Glass
Diamond
Nylon
Quartz
INS
UL
AT
OR
SS
EM
ICO
ND
UC
TO
RS
ME
TA
LS
INC
RE
AS
ING
DO
PIN
G L
EV
EL
S
Conductivity increases with increased doping
S/cm
Doped trans-(CH)x
[105 S/cm]
Doped polyaniline
[103 S/cm]
trans-(CH)x
[10-5 S/cm]
Polyaniline
[10-10 S/cm]
Electrospinning
High Voltage
Supply
Polymer
solution
Cathode
Fibers
Polystyrene in THF (MW 212,000) – 20kV/ 20cm Average diameter 60 nm
MacDiarmid, Johnson, Pinto, Synth. Metals 119, 27 (2001)
(a) (b)
(c) (d)
H H
FF F
H
n
F
F
m
Figure 1: Chemical structure of 4-polyethylenedioxythiophene (PEDOT)
doped with poly(styrene sulfonic acid) (PSS) PEDOT-PSS blend (Baytron P).
PSS
PEDOT
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
Figure 1: Chemical structure of 4-polyethylenedioxythiophene (PEDOT)
doped with poly(styrene sulfonic acid) (PSS) PEDOT-PSS blend (Baytron P).
PSS
PEDOT
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
SO3 -
SO3
SO3SO
3SO3 -
SO3 -SO
3
H
SO3 H
SO3
H
H H
H
SSS S
O O
S
O O O O
S
O O
S
O O
O O
S
O O
O O
S
O O
+++
(b)
(a)
PVDF-TrFE/PEDOT-PSSA
(a) (b)
(c) (d)
(e) (f)
PVDF-TrFE/PEDOT-PSSA
Pinto, Macromolecules 42, 7924 (2009).
Diameter comparison between human hair and e-spun fiber
N.J. Pinto (ACS Book Chapter 2010)
Substrates
SiO2
Isolated polymer nanofibers
5mm
50 mm
0 5 10 15 mm
250
0
-250
nm
I V
(b)
(a)
VB (V)
0 1 2 3 4 5
I (n
A)
0
10
20
30
s = 0.08 S/cm
Simple resistor (PANi-HCSA)
Pinto, Am. J. Phys. 76, 1163 (2008).
0 500 1000 1500 2000
R/R
N
0
1
2
3
N2
methanol
T(s)
0 500 1000 1500 2000
R/R
N
0
1
2
3
methanol
N2
Gas sensor (PANi-HCSA)
Pinto, Johnson, MacDiarmid, Sens. Actuator B 129 , 621 (2008).
EF EF
EC
EV
EF
EC
EV
EF
EC
EV
EF
EC
EV
EF
EF
EF
Metal semiconductor
before contact
Metal semiconductor
after contact
Metal semiconductor
junction under reverse
bias
Metal semiconductor
junction under forward
bias
Metal
n-doped Si
Schottky Diode
Schottky nano-diode (contd.) n-doped Si/SiO2 (r=0.1-1.0 W-m)
Vbias
I SiO2n-doped Si
Au electrode
Electrospun fiber
cleaved surface
Schottky diode using PANi nanofibers
Au contact
Si-- contact
fiber
Device characteristics at 300 K
• Ifor/Irev = 30
• Ideality factor n 4
• 0.4 V < Von < 0.6 V
• b = 0.49 V
Vbias (V)
-1.0 -0.5 0.0 0.5 1.0
I (n
A)
-2
-1
0
1
2
Diode / Sensor
Vbias (V)
-2 -1 0 1 2
I (n
A)
0.0
0.4
0.8
1.2
1.6
vac
vac
NH3
Pinto, Johnson, MacDiarmid, Appl. Phys. Lett. 89, 033505 (2006).
Field effect transistor ([P(ND12OD-T2]n*)
* poly[N,N-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyll-alt-5,5-(2,2-bithiophene)]
Rosado, Pinto, IJCE 6, 175 (2013).
VDS (V)
0 10 20 30 40I D
S (
nA
)
0.0
0.1
0.2
0.3
0.4
0.5
0 V
40 V
60 V
80 V
100 V
VDS
(V)
0 20 40 60 80 100
I DS (
nA
)
0
50
100
150
200
70V
30V0V
Effect of UV radiation ([P(ND12OD-T2]n*)
Rosado, Pinto, PMSE Preprints 109, 1 (2013).
t (s)
0 100 200 300 400
R (
GW
)
4
8
UVOFF
UVON
50mm
P3HT SnO2
Crossed nanofibers: n-SnO2 and p-P3HT
0 1 2 3 4 5
I DS
(nA
)
0.00
0.04
0.08
0.12
VDS (V)
-5 -4 -3 -2 -1 0
I DS
(nA
)
-0.6
-0.4
-0.2
0.0
5V
5V
0V0V
-5V
-5V
Crossed nanofibers: n-SnO2 and p-P3HT
VG VDS
VGS IDS
Si++
V (V)-4 -2 0 2 4
I (p
A)
0
100
200
300
400
LUMO
HOMO
EC
EV
EF
EG=2.2V
EG=3.6V
Crossed nanofibers: n-SnO2 and p-P3HT
Pinto, Agarwal, Appl. Phys. Lett. 94, 083504 (2009).
V (V)-4 -2 0 2 4
I (p
A)
-60
-40
-20
0
20
40
60
80
Crossed nanofibers: n-SnO2 and PEDOT-PSSA
75 mm
SnO2
PEDOT-PSSA
VG VDS
VGS IDS
Si++
V (V)
-1.0 -0.5 0.0 0.5 1.0
I ( m
A)
-6
-4
-2
0
2
4
6
I ( m
A)
-0.2
-0.1
0.0
0.1
0.2
-40V
0V
+40V
V (V)
-1.0 -0.5 0.0 0.5 1.0
I ( m
A)
0.0
0.5
1.0
1.5
T (s)
0.0 0.1 0.2 0.3
V (
V)
-2
0
2
Carrasquillo, Pinto, Mat. Sci. Engg. B 177, 805 (2012).
Crossed nanofibers: n-SnO2 and PEDOT-PSSA
P3HT
PEDOT
Crossed nanofibers: p-P3HT and PEDOT-PSSA
VDS
(V)
-4 -2 0
I DS (
nA
)
-0.4
-0.2
0.0
VGS
(V)-40 -20 0
I DS (
pA
)
-40
-20
0
0V, -10V
-20V
-30V
-40V
-50V
Crossed nanofibers: p-P3HT and PEDOT-PSSA
VDS
VGS IDS
Si++
VTS
+1V
0V
-1V
-2V
-3V
-4V
-5V
-50 -40 -30 -20 -10 0
I T (
nA
)
-1.2
-0.8
-0.4
0.0
VGS
(V)
-50 -40 -30 -20 -10 0
I DS (
nA
)
-0.6
-0.4
-0.2
0.0
VTS
(V)
-4 -2 0
m (
cm2
/Vs)
10-3
10-2
-4.9 eV
-5.0 eV
-5.1 eV
Au(D) P3HT PEDOT P3HT Au(S)
-5.1 eV E
VTS = 0
VTS < 0
E
Crossed nanofibers: p-P3HT and PEDOT-PSSA
VDS
IDS
VGS VTS 1 2
3
4
Conclusions
Electrospinning is a simple technique to make fibers
Diodes, FET’s, Sensors
Some of these devices are multifunctional
All of the work presented was done by High School students and Undergraduates
Acknowledgements
National Science Foundation
DoD
Final Questions
Please type all questions into the Chat Box
Whether you are joining us live or watching the recorded version of this webinar, please take 1 minute to provide your feedback and
suggestions.
How Can We Better Serve You?
http://questionpro.com/t/ABkVkZQFNq
To access this recording, slides, and handout visit
nano4me.org/webinars.php
Webinar Recordings
If you attended the live version of this
1.5 hour webinar and would like a
certificate of participation, please email:
Certificate of Participation
Aug 11 – 14: Nanotechnology Course Resources II: Patterning,
Workshop Characterization, and Applications
June 4 – 6: MNT Conference, Albuquerque, NM
July 21 – 24: HI-TEC Conference, Chicago, IL
Want more events? Visit www.nano4me.org/webinars for more
details about these and other upcoming workshops and webinars in
2014.
2014 Events Calendar
Thank you for attending the NACK Network webinar:
Electrospinning Polymer Fibers:
A Simple Technique of Introducing
Nanoscience to Undergraduates
Thank you!