High concentration Synthesis of Sub-10 nm Copper Nanoparticles for ...
Supporting Information
High concentration Synthesis of Sub-10 nm Copper
Nanoparticles
for
Application
to
Conductive Nanoinks Yuki Hokita, Mai Kanzaki, Tomonori Sugiyama, Ryuichi Arakawa, and Hideya Kawasaki*
Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate-cho, Suita 564-8680, Japan
Corresponding author's email address: [email protected]
S-1
Figure S1. XRD pattern for Cu nanoink(40 wt% Cu) after four months from the preparation of the nanoink. The resistivity of the conductive Cu film obtained from the Cu nanoink on polyimide film was 80 cm after thermal heating at 150 C for 15 min under a nitrogen flow. The resistivity of Cu film from the nanoink after the prolonged time of four months has tripled compared to the case (~30 cm) just after the preparation. 70
Numbers of NPs
60 50 40 30 20 10 0
1.0
Figure S2.
2.0
3.0
4.0
Diameters / nm
5.0
6.0
The size distribution diagram of AmIP-Cu NPs.
S-2
0
(a)
(b)
Weight loss / %
-10
-20
-30
-40
-50
80
160
240
320
400
480
560
Temperature/C
Figure S3. (a) TEM image of 2 nm Cu NPs via a microwave-assisted polyol method.1 (b) TGA curve of 2 nm Cu NPs at a heating rate of 10 C/min under a N2 flow.
Transmittance/ %
100
90
80
70
60
50 4000 3600 3200 2800 2400 2000 1600 1200 800
Wavenumber/cm-1 Figure S4. IR spectrum of Cu film after the thermal sintering of Cu nanoink (45 wt% Cu, propylene glycol/glycerol solvent [1:1 vol%]) for 15 min at the temperature of 150 C.
S-3
(a)
(b)
(c)
Figure S5. TEM images of Am-IP Cu NPs synthesized with different addition rates of hydrazine: (a) one-time addition, (b) drop-wise addition of hydrazine at a rate of 8 L/s, and (c) drop-wise addition of hydrazine at a rate of 24 L/s.
100 nm
200 nm
Figure S6. TEM images of 3-amino-1-propanol AmNP-Cu NPs synthesized with the same synthetic conditions as AmIP-Cu NPs (except for the use of AmNP). The AmNP-Cu NPs were synthesized in ethylene glycol solution with a high-concentration of copper (II) acetate (300 mM) under ambient air conditions and at room temperature using AmNP as the stabilizer and hydrazine monohydrate as the reducing agent. S-4
(a)
(b)
Cu(0)
Cu(0)
Figure S7. The XRD patterns of Cu2O powder (a) before the heat treatment and (b) after the heat treatment in AmIP (45 wt% Cu2O powder) at 150 C for 30 min under a N2 atmosphere. After the heat treatment, the AmIP partly reduced Cu2O powder to metallic copper, as denoted by the red arrows in Fig. S7 (b).
S-5
(a)
0
(b) Weight / %
6%
60
-5
40
5%
-10
20
Heat Flow / mV
80
2.5%
0 -15 100
Transmittance/ %
(c)
300
400
Temperature / ℃
100nm 100
200
(d) (c)
80 60 40 20 0 4000 3500 3000 2500 2000 1500 1000
Wavenumber/cm-1
30
40
50
60
70
80
90
2θ
Figure S8. (a) TEM image of AmNP-Cu NPs with the size of 5.8 1.0 nm. (b) TGA-DTA curves of the AmNP-Cu NPs at a heating rate of 10 C/min under a N2 flow. (c) ATR-IR spectrum of Cu film after the thermal sintering of AmNP-Cu based nanoink (40 wt% Cu, propylene glycol/glycerol solvent [1:1 vol%]) for 30min at the temperature of 150 C. (d) XRD pattern for Cu film after the thermal sintering of AmNP-Cu NP based nanoink (40 wt% Cu, propylene glycol/glycerol solvent [1:1 vol%]) for 30 min at 180 C.
Synthesis of single nano-sized Am NP-Cu NPs with the sizes of 5.8 1.0 nm: In a typical synthesis, 3-amino-1-propanol (AmNP)-Cu NPs were synthesized in the AmNP solution by the hydrazine reduction of copper (II) acetate under ambient air conditions at room temperature. Typically, solid copper (II) acetate of 0.91 g was added into pure AmNP solution of 45 mL at room temperature, obtaining a blue solution due to the formation of AmNP-Cu complex, corresponding to 100 mM Cu salt. Then, hydrazine monohydrate of 4.86 mL was at once added to the blue solution under stirring at 1100 rpm at room temperature, and kept for under these conditions for about 24 h. The AmNP-Cu NPs were precipitated by adding excess N-N-dimethylacetamide to the colloidal dispersion of Cu NPs, and the precipitates were washed with toluene and hexane. S-6
Reference 1) Kawasaki, H.;Kosaka,Y.;Myoujin, Y.; Narushima, T.;Yonezawa, T.; Arakawa, R. Microwave-assisted polyol synthesis of copper nanocrystals without using additional protective agents, Chem. Commun. 2011, 47, 7740-7742.
S-7
High concentration Synthesis of Sub-10 nm Copper
Nanoparticles
for
Application
to
Conductive Nanoinks Yuki Hokita, Mai Kanzaki, Tomonori Sugiyama, Ryuichi Arakawa, and Hideya Kawasaki*
Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate-cho, Suita 564-8680, Japan
Corresponding author's email address: [email protected]
S-1
Figure S1. XRD pattern for Cu nanoink(40 wt% Cu) after four months from the preparation of the nanoink. The resistivity of the conductive Cu film obtained from the Cu nanoink on polyimide film was 80 cm after thermal heating at 150 C for 15 min under a nitrogen flow. The resistivity of Cu film from the nanoink after the prolonged time of four months has tripled compared to the case (~30 cm) just after the preparation. 70
Numbers of NPs
60 50 40 30 20 10 0
1.0
Figure S2.
2.0
3.0
4.0
Diameters / nm
5.0
6.0
The size distribution diagram of AmIP-Cu NPs.
S-2
0
(a)
(b)
Weight loss / %
-10
-20
-30
-40
-50
80
160
240
320
400
480
560
Temperature/C
Figure S3. (a) TEM image of 2 nm Cu NPs via a microwave-assisted polyol method.1 (b) TGA curve of 2 nm Cu NPs at a heating rate of 10 C/min under a N2 flow.
Transmittance/ %
100
90
80
70
60
50 4000 3600 3200 2800 2400 2000 1600 1200 800
Wavenumber/cm-1 Figure S4. IR spectrum of Cu film after the thermal sintering of Cu nanoink (45 wt% Cu, propylene glycol/glycerol solvent [1:1 vol%]) for 15 min at the temperature of 150 C.
S-3
(a)
(b)
(c)
Figure S5. TEM images of Am-IP Cu NPs synthesized with different addition rates of hydrazine: (a) one-time addition, (b) drop-wise addition of hydrazine at a rate of 8 L/s, and (c) drop-wise addition of hydrazine at a rate of 24 L/s.
100 nm
200 nm
Figure S6. TEM images of 3-amino-1-propanol AmNP-Cu NPs synthesized with the same synthetic conditions as AmIP-Cu NPs (except for the use of AmNP). The AmNP-Cu NPs were synthesized in ethylene glycol solution with a high-concentration of copper (II) acetate (300 mM) under ambient air conditions and at room temperature using AmNP as the stabilizer and hydrazine monohydrate as the reducing agent. S-4
(a)
(b)
Cu(0)
Cu(0)
Figure S7. The XRD patterns of Cu2O powder (a) before the heat treatment and (b) after the heat treatment in AmIP (45 wt% Cu2O powder) at 150 C for 30 min under a N2 atmosphere. After the heat treatment, the AmIP partly reduced Cu2O powder to metallic copper, as denoted by the red arrows in Fig. S7 (b).
S-5
(a)
0
(b) Weight / %
6%
60
-5
40
5%
-10
20
Heat Flow / mV
80
2.5%
0 -15 100
Transmittance/ %
(c)
300
400
Temperature / ℃
100nm 100
200
(d) (c)
80 60 40 20 0 4000 3500 3000 2500 2000 1500 1000
Wavenumber/cm-1
30
40
50
60
70
80
90
2θ
Figure S8. (a) TEM image of AmNP-Cu NPs with the size of 5.8 1.0 nm. (b) TGA-DTA curves of the AmNP-Cu NPs at a heating rate of 10 C/min under a N2 flow. (c) ATR-IR spectrum of Cu film after the thermal sintering of AmNP-Cu based nanoink (40 wt% Cu, propylene glycol/glycerol solvent [1:1 vol%]) for 30min at the temperature of 150 C. (d) XRD pattern for Cu film after the thermal sintering of AmNP-Cu NP based nanoink (40 wt% Cu, propylene glycol/glycerol solvent [1:1 vol%]) for 30 min at 180 C.
Synthesis of single nano-sized Am NP-Cu NPs with the sizes of 5.8 1.0 nm: In a typical synthesis, 3-amino-1-propanol (AmNP)-Cu NPs were synthesized in the AmNP solution by the hydrazine reduction of copper (II) acetate under ambient air conditions at room temperature. Typically, solid copper (II) acetate of 0.91 g was added into pure AmNP solution of 45 mL at room temperature, obtaining a blue solution due to the formation of AmNP-Cu complex, corresponding to 100 mM Cu salt. Then, hydrazine monohydrate of 4.86 mL was at once added to the blue solution under stirring at 1100 rpm at room temperature, and kept for under these conditions for about 24 h. The AmNP-Cu NPs were precipitated by adding excess N-N-dimethylacetamide to the colloidal dispersion of Cu NPs, and the precipitates were washed with toluene and hexane. S-6
Reference 1) Kawasaki, H.;Kosaka,Y.;Myoujin, Y.; Narushima, T.;Yonezawa, T.; Arakawa, R. Microwave-assisted polyol synthesis of copper nanocrystals without using additional protective agents, Chem. Commun. 2011, 47, 7740-7742.
S-7
