The Effect of Surface Functionalization of Graphene … Effect of Surface Functionalization of...
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The Effect of Surface Functionalization of Graphene on the Electrical Conductivity of Epoxy-based Conductive Nanocomposites by Behnam Meschi Amoli, PhD Institute for Polymer Research, Waterloo Institute of Nanotechnology, Department of Chemical Engineering, University of Waterloo, Waterloo, ON, Canada May 6, 2015 1
Transcript of The Effect of Surface Functionalization of Graphene … Effect of Surface Functionalization of...
The Effect of Surface Functionalization of Graphene on the Electrical Conductivity
of Epoxy-based Conductive Nanocomposites
by
Behnam Meschi Amoli, PhD
Institute for Polymer Research, Waterloo Institute of Nanotechnology, Department of Chemical Engineering, University of Waterloo, Waterloo, ON, Canada
May 6, 20151
OUTLINE
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Introduction
Hybrid Filler System using Graphene
Ag NP-decoration
SDS-stabilization
Concluding remarks
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Introduction
INTRODUCTION
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Interconnection Materials for Electronic Packaging Technologies
Electrically Conductive Pathways Between Different Elements
Li et al., Science, 2005
Lead-based solders
Lead-free materials
Electrical Conductive Adhesives (ECAs)
INTRODUCTION
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Polymeric Matrix Conductive Fillers
Epoxy Micron-sized silver flakes
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INTRODUCTION
Commercial ECAs
Environmental friendliness
Mild processing conditions
Low stress on substrate
Fine pitch interconnect capability
Advantages Disadvantages
Poor mechanical strength
Conductivity fatigue in harsh
conditions (reliability)
Low electrical conductivity
Addition of more silver flakes
Decreases the adhesive strength
Increases the final cost
Not effective after percolation threshold
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Adding nano-sized fillers to the conventional formulation of ECAs to generate hybrid (micro-nano) filler system
INTRODUCTION
Objective:
Improving the quality of interactions between conductive fillers to
facilitate the electron transportation
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NP
Adding nano-sized fillers to the conventional formulation of ECAs to generate hybrid (micro-nano) filler system
INTRODUCTION
Spherical Ag NPsHigh aspect-ratio Ag NBsGraphene
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Hybrid Filler System
Using
Graphene
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GRAPHENE
Flat monolayer of carbon atoms
Densely packed into a 2D honeycomb lattice structure
The thinnest and stiffest 2D nanostructure
Extremely high aspect-ratio and electrical conductivity
Surfactants (SDS)
Two functionalization approaches
Surface decoration with Ag NPs
Acid treatment
COOH
COOHCOOH
COOH
COOH
COOH
COOHCOOH
COOH
COOH
HOOC
COOH
COOH
COOH
COOH
OH
OH
OH
OHOH
OH
OH
OH
+
+
+
+
+
+
+
+ +
+
+
+
++
+
+ +
+
+
++
+
+
+
++
+
+
+
+
(1)
(4)(3)
(2)
Silv
er n
itrate
MPA+
NaBH4
S
O
OH
Ag NPs+
Ag nucleation sites
Ag ions
Covalent approachNon-covalent approach
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Ag NP-DECORATED GRAPHENE
o Surface decoration of graphene with Ag NPs functionalized with MPA
Preparation of GO Initial nucleation
Formation and functionalization of NPs
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015
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AG NP-DECORATED GRAPHENE
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015
The Average Size9.1 ± 3.1 nm
𝟒. 𝟔 × 𝟏𝟎−𝟓 𝜴. 𝒄𝒎
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AG NP-DECORATED GRAPHENE
o Hybrid ECAs using the Ag NP-decorated graphene
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015
Hybrid ECAs have1 wt% graphene
Bulk resistivity of lead-based solders ≈
2 × 𝟏𝟎−𝟓 𝜴. 𝒄𝒎
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SDS-STABILIZED GRAPHENE
o The stabilization of graphene using SDS
B. Meschi Amoli et al., Carbon, accepted, 2015
Sonication
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SDS-STABILIZED GRAPHENE
o Hybrid ECAs using the SDS-stabilized graphene
B. Meschi Amoli et al., Carbon, accepted, 2015
Small Gr≤ 1µm
Large Gr≤ 5µm
1. 𝟔 × 𝟏𝟎−𝟓 𝜴. 𝒄𝒎7 × 𝟏𝟎−𝟓 𝜴. 𝒄𝒎
Compared to 1.8 × 𝟏𝟎−𝟒 𝜴. 𝒄𝒎
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Concluding remarks
o Both functionalization approaches improved the electrical conductivity of ECAs
o SDS-stabilization of graphene is more effective method for electrical conductivity improvement compared to Ag NP-decoration
o A relatively low electrical resistivity of 35 Ω.cm was achieved using only 10 wt% silver flakes and 1.5 wt% SDS-stabilized graphene
o A highly electrically conductive adhesive with the bulk resistivity less than that of lead-based solder was fabricated using 1.5 wt% SDS-stabilized graphene and 80 wt% silver flakes
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• Meschi Amoli et al., J. Mater. Chem., 2012, 20048–20056.
• Gumfekar, Meschi Amoli et al., Poly. Sci. B: Poly. Phys., 2013, 1448–1455.
• Meschi Amoli et al., Macromol. Mater. Eng., 2014, 739–747.
• Meschi Amoli et al., J. Mater. Sci: Mater Electron., 2015, 590–600.
• Meschi Amoli et al., Carbon, 2015, accepted.
• Meschi Amoli et al., J. Mater. Sci: Mater Electron., 2015, accepted.
LIST OF PUBLICATIONS
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AKNOWLEDGEMENTS
Supervisors
◦ Professor Boxin Zhao
◦ Professor Norman Zhou
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THANK YOU!
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Backup Slides
Curing Mechanism of Epoxy
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INTRODUCTION
Electron conduction mechanism in an electrical network
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MUA MPA
AgNO3 + HS(CH2)nCOOH
B. Meschi Amoli et al., J. mater. chem., 2012
Ag-MUA
Ag-MPA
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Ag NP-DECORATED GRAPHENE
o Surface decoration of graphene with Ag NPs-functionalized with MPA
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015, 590–600,
900 1400 1900 2400 2900 3400 3900
Ab
sorp
tio
n (
a.u
.)
Wavenumber (cm ¹ )
Gr-Ag NPs
Graphene
GrO
17041617
OH
1696
1228
1247 1587
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Ag NP-DECORATED GRAPHENE
o Initial nucleation
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015, 590–600,
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Ag NP-DECORATED GRAPHENE
o UV-vis & XRD
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015, 590–600,
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AG NP-DECORATED GRAPHENE
o Thermal behaviour of the decorated graphene
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015, 590–600,
145 °C
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AG NP-DECORATED GRAPHENE
o Electrical Conductivity of Conductive fillers thin-films
B. Meschi Amoli et al., J. Mater. Sci: Mater Electron. 2015, 590–600,
Temperature Increase
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SDS-STABILIZED GRAPHENE
o The stabilization of graphene using SDS
B. Meschi Amoli et al., Carbon, under revision, 2015
0.30 nm
0.38 nm
FTIR
XRD
Raman
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SDS-stabilized Graphene
B. Meschi Amoli et al., Carbon, under revision, 2015
0.65
0.7
0.75
0.8
0.85
0.9
0.95
75 80 85 90 95 100 105 110 115 120 125 130 135 140
Re
v C
p (
J/g
)
Temperature (°C)
Cp Tg Analysis
Tg : 111.9 °C
103.95 °C
103.95 °C
Name
Description
Composition
Control 1
(Neat Epoxy)
Control 2
(Ethanol Diluted) HCA-SGN HCA-SGS
Ethanol ContentPHR 0 PHR 40.8 PHR 40.4 PHR 40.4 PHR
wt% 0 wt% 26.5 wt% 12.5 wt% 12.5 wt%
∆Htot J/g 452.7 380.5 132.7 148.3
∆Hnorm J/gmatrix 452.7 517.5 380.9 436.2
Tg °C 129.7 117.8 111.9 111.9
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SDS-STABILIZED GRAPHENE
B. Meschi Amoli et al., Carbon, under revision, 2015
Name
Description
Composition
Control 1
(Neat Epoxy)
Control 2
(Ethanol Diluted) HCA-SGN HCA-SGS
Ethanol ContentPHR 0 PHR 40.8 PHR 40.4 PHR 40.4 PHR
wt% 0 wt% 26.5 wt% 12.5 wt% 12.5 wt%
∆Htot J/g 452.7 380.5 132.7 148.3
∆Hnorm J/gmatrix 452.7 517.5 380.9 436.2
Tg °C 129.7 117.8 111.9 111.9
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SDS-stabilized Graphene
B. Meschi Amoli et al., Carbon, under revision, 2015
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SDS-stabilized Graphene
o Thermal Stability
B. Meschi Amoli et al., Carbon, under revision, 2015
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SDS-STABILIZED GRAPHENE
o Hybrid ECAs using the SDS-stabilized graphene
B. Meschi Amoli et al., Carbon, under revision, 2015
Small SDS-Gr
Large SDS-Gr Large non modified Gr
No Gr
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5.50E-04
7.00E-53.50E-5
1.80E-04
3.00E-05 1.60E-05
0.00E+00
1.00E-04
2.00E-04
3.00E-04
4.00E-04
5.00E-04
6.00E-04
7.00E-04
Res
isti
vity
(Ω
∙cm
)
Conventional ECA Non-modified small Gr non-modified large Gr
AG NP decorated Gr SDS-Stabilized Gr (small) SDS Stabilized Gr (large)
