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Electronic Supplementary Information (ESI)
An Alternative Approach to Develop Highly Sensitive and Selective
Chemosensor for the Colorimetric Sensing of Cyanide in Water
Xiaoding Lou,a Liyao Zhang,b Jingui Qin,*, a and Zhen Li a, *
a
Department of Chemistry, Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials,
Wuhan University, Wuhan, 430072, China. Fax: 86 27 68756757; Tel: 86 27 62254108; E-mail:
[email protected] and [email protected].
b
College of Life Science, Wuhan University, Wuhan 430072, China
Experimental Section
Materials and Instrumentations
All reagents were of analytical reagent grade and used without further purification. Doubly
distilled water was used for all experiments. Cu(NO3)2·3H2O, NaCN, KSCN, NaCl, KBr, KI,
NaHSO4, Na2SO4, NaH2PO4·2H2O, NaClO4, NaNO2, NaIO3, NaF, KOH and Zincon were purchased
from Sinopharm Chemical Reagent Beijing Co., Ltd. UV-visible spectra were obtained using a
Shimadzu UV-2550 spectrometer, and the pH values were determined by using a DELTA 320 PH
dollar.
Preparation of solutions of metal ions and anions
0.1 mmol of each inorganic salt (Cu(NO3)2·3H2O, 24.2 mg; NaCl, 5.8 mg; KSCN, 9.8 mg; KBr,
11.9 mg; KI, 16.6mg; Na2SO4, 14.2 mg; NaClO4, 12.2 mg; NaF, 4.2 mg; NaNO2, 6.9mg; NaHSO4,
12mg; NaIO3, 19.8mg; NaH2PO4·2H2O, 15.6 mg; NaCN, 4.9mg; Zincon, 44mg) was dissolved in
distilled water (10 mL) to afford 1×10-2 mol/L aqueous solution. The stock solutions could be diluted
to desired concentrations with water when needed, and the pH values were adjusted by the addition
of the concentrated solution of potassium hydroxide with the aid of a pH meter.
UV absorption changes of zincon by Cu2+
UV absorption changes of zincon (5.0×10-5 mol/L) were recorded before and after the addition
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of Cu2+ to the solution of zincon. The same work was conducted at the pH value of 8.2 and 9.1.
UV absorption changes of zincon+Cu2+ with CNThe solution of zincon (5.0×10-5 mol/L) and NaCN (1×10-3 mol/L) were prepared in distilled
water, and the pH values were adjusted by the addition of the concentrated solution of potassium
hydroxide with the aid of a pH meter. A solution of zincon was placed in a quartz cell (10.0 mm
width) and the UV Absorption spectrum was recorded. After the solution of Cu2+ (2.2×10-5 mol/L)
was added to zincon (5.0×10-5 mol/L), the solution of NaCN was introduced in portions (the
concentrations of the NaCN were 5.0×10-6, 1.0×10-5, 1.5×10-5, 2.0×10-5, 3.0×10-5, 4.0×10-5, 5.0×10-5,
6.0×10-5, 7.0×10-5 mol/L) and the UV absorption changes were recorded at room temperature each
time. The same work was conducted at the pH value of 8.2 and 9.1.
UV absorption changes of zincon+Cu2+ with other anions
The solution of zincon (5.0×10-5 mol/L) and anions were prepared in distilled water, and the pH
values were adjusted by the addition of the concentrated solution of potassium hydroxide with the
aid of a pH meter. UV absorption changes of zincon (5.0×10-5 mol/L) + Cu2+ (2.2×10-5 mol/L) were
recorded before and after the addition of anions to the solution of zincon. The same work was
conducted at the pH value of 8.2 and 9.1.
UV absorption changes of zincon+Cu2+ with CN- and other anions
Then UV absorption changes of zincon (5.0×10-4 mol/L) + Cu2+ (2.2×10-5 mol/L) were recorded
before and after the addition of NaCN and all the other anions (5.0×10-5 mol/L). The same work was
conducted at the pH value of 8.2 and 9.1.
UV absorption changes of zincon+Cu2+ with FUV absorption changes of zincon (5.0×10-5 mol/L) + Cu2+ (2.2×10-5 mol/L) were recorded
before and after the addition of F- to the solution of zincon.
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Supplementary Material (ESI) for Chemical Communications
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Equation S1: the reaction between Cu2+ and CN2Cu2+ + 4CN- = 2CuCN + (CN)2
(CuCN is white precipitant).
Equation S2: the reaction between CuCN and CNCuCN + (x-1)CN- = [Cu(CN)x]1-x, (x = 2, 3, or 4)
The stability constants (K), [Cu(CN)2]-: K = 1.00 ×1024; [Cu(CN)4]3-: K = 2.00 ×1030.
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2.0
2+
-5
Cu (X10 M)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Absorption (au)
1.5
1.0
0.5
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S1. UV-vis spectra of zincon with increasing amounts of Cu2+ in water. The concentration of
zincon was 1.0×10-4 mol/L.
1.4
1.2
-
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0.0
1.0
Absorption (au)
-5
CN (X10 M)
0.8
0.6
0.4
0.2
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S2. UV-vis spectra of the mixture solution of zincon (1.0×10-4 mol/L) and Cu2+ (4.0×10-5
mol/L) with increasing amounts of CN- in water.
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0.5
A-A0 (au)/λ463 nm
0.4
0.3
0.2
0.1
0.0
0.0
0.5
1.0
1.5
2.0
-
[CN ] (ppm)
Figure S3. Absorption difference at λ= 463 nm versus the concentration of CN- in water with the
concentrations of zincon and Cu2+ at 5.0×10-5 and 2.2×10-5 mol/L , respectively.
2.0
A(λ463nm)/A(λ600nm)
1.6
1.2
0.8
0.4
0.0
0.0
0.5
1.0
1.5
2.0
ppm
Figure S4. Absorption difference A(463nm)/A(600nm) versus the concentration of CN- in water
with the concentrations of zincon and Cu2+ at 5.0×10-5 and 2.2×10-5 mol/L , respectively.
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Supplementary Material (ESI) for Chemical Communications
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0.7
_
CN
_
Cl
_
I
_
SCN
_
IO3
Absorption (au)
0.6
0.5
_
2
SO4
0.4
_
NO2
_
0.3
Br
_
H2PO4
0.2
HSO4
_
_
ClO4
0.1
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S5. UV-vis spectra of zincon at the presence of different anions (5.0×10-5 mol/L) in water.
The concentration of zincon was 5.0×10-5 mol/L.
0.7
_
CN
_
SCN
_
NO2
0.6
Absorption (au)
0.5
_
Cl
_
Br
_
H2PO4
0.4
_
I
_
ClO4
0.3
_
IO3
0.2
_
HSO4
0.1
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S6. UV-vis spectra of zincon (5.0×10-5 mol/L) at the presence of different anions (2.5×10-4
mol/L) in water. The concentration of cyanide was 5.0×10-5 mol/L.
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0.8
-
5.0
4.0
3.0
2.0
1.5
1.0
0.8
0.5
0.4
0.3
0.0
0.6
Absorption (au)
-4
F (X10 M)
0.7
0.5
0.4
0.3
0.2
0.1
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S7. UV-vis spectra of the mixture solution of zincon (5.0×10-5 mol/L) and Cu2+ (2.2×10-5
mol/L) with increasing amounts of F- in water. The stability constant (K) was calculated to be
4.8×104.
0.5
A-A0 (au)/λ463nm
0.4
0.3
0.2
0.1
0.0
0
2
4
6
8
10
-
[ F ] (ppm)
Figure S8. Absorption difference at λ= 463 nm versus the concentration of F- in water with the
concentrations of zincon and Cu2+ at 5.0×10-5 and 2.2×10-5 mol/L , respectively.
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Supplementary Material (ESI) for Chemical Communications
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Figure S9. Different solutions of zincon and copper ions in water (5.0×10-5 and 2.2×10-5 mol/L,
respectively) in the presence of anion (5.0×10-5 mol/L). From left to right: no anion, CN-, Cl-, I-, IO3-,
SO42-, NO2-, Br-, H2PO4-, HSO4-, ClO4-.
Figure S10. Different solutions of zincon and copper ions in water (5.0×10-5 and 2.2×10-5 mol/L,
respectively) in the presence of different concentrations of F-. From left to right (×10-5 mol/L): 0, 3.0,
5.0, 8.0, 10.0, 15.0, 20.0, 30.0, 40.0 and 50.0.
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Figure S11. Different solutions of zincon and copper ions in water (5.0×10-5 and 2.2×10-5 mol/L,
respectively) in the presence of anion (5.0×10-5 mol/L). From left to right: no anion, F-, Cl-, I-, IO3-,
SO42-, NO2-, Br-, H2PO4-, HSO4-, ClO4-.
1.0
Absorption (au)
2+
-5
Cu ( X10 M)
463 nm
0.8
0.0
0.3
0.9
1.2
1.4
1.6
1.8
2.0
2.2
0.6
600 nm
0.4
0.2
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S12. UV-vis spectra of zincon with increasing amounts of Cu2+ in water. The concentration
of zincon was 5.0×10-5 mol/L. The pH value of the solution was about 8.2.
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Supplementary Material (ESI) for Chemical Communications
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1.0
-
-5
CN (X10 M)
Absorption (au)
0.8
15
12
11
10
8.0
5.0
3.0
2.0
1.5
1.0
0.5
0.0
0.6
0.4
0.2
0.0
250
350
450
550
650
Wavelength (nm)
750
850
Figure S13. UV-vis spectra of the mixture solution of zincon (5.0×10-5 mol/L) and Cu2+ (2.2×10-5
mol/L) with increasing amounts of CN- in water. The pH value of the solution was about 8.2.
1.0
-
-5
CN (X10 M)
Absorption (au)
0.8
15
12
10
8.0
5.0
3.0
2.0
1.5
1.0
0.5
0.0
0.6
0.4
0.2
0.0
250
350
450
550
650
Wavelength (nm)
750
850
Figure S14. UV-vis spectra of the mixture solution of zincon (5.0×10-5 mol/L) and Cu2+ (2.2×10-5
mol/L) with increasing amounts of CN- in water. The pH value of the solution was about 9.1.
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Supplementary Material (ESI) for Chemical Communications
This journal is (C) The Royal Society of Chemistry 2008
0.8
_
CN
_
H2PO4
_
Cl
_
IO3
Absorption (au)
0.6
_
F
_
I
_
2
SO4
0.4
_
SCN
_
NO2
_
Br
_
HSO4
0.2
_
ClO4
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S15. UV-vis spectra of zincon at the presence of different anions (5.0×10-5 mol/L) in water.
The concentration of zincon was 5.0×10-5 mol/L. The pH value of the solution was about 8.2.
0.8
_
CN
_
F
_
H2PO4
Absorption (au)
0.6
_
2
SO4
_
Cl
_
I
_
SCN
_
NO2
0.4
_
Br
_
HSO4
_
ClO4
0.2
_
IO3
0.0
250
350
450
550
650
750
850
Wavelength (nm)
Figure S16. UV-vis spectra of zincon at the presence of different anions (5.0×10-5 mol/L) in water.
The concentration of zincon was 5.0×10-5 mol/L. The pH value of the solution was about 9.1.
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1.0
2+
_
Zincon+Cu +CN
_
0.8
2+
_
_
_
+I ,HSO4,Br ,Cl ,
_
Zincon+Cu +CN
_
_
_
_
_
2-
IO3,F ,SCN ,NO2
_
Absorption (au)
H2PO4,ClO4,SO4
0.6
2+
_
Zincon+Cu +I
_
_
_
2HSO4,Br ,Cl ,SO4
0.4
_
_
_
_
IO3,F ,SCN ,NO2
_
_
H2PO4,ClO4
0.2
2+
Zincon+Cu
0.0
300
400
500
600
700
800
Wavelength (nm)
Figure S17. UV-vis spectra of zincon at the presence of different anions mixture(5.0×10-5 mol/L) in
water. The concentration of zincon was 5.0×10-5 mol/L and Cu2+ was 2.2×10-5 mol/L. The pH value
of the solution was about 8.2.
0.8
2+
2+
_
Zincon+Cu +CN
_
Zincon+Cu +CN
_
_
_
_
+I ,HSO4,Br ,Cl ,
_
_
_
_
_
2-
IO3,F ,SCN ,NO2
0.6
_
Absorption (au)
H2PO4,ClO4,SO4
0.4
2+
_
Zincon+Cu +I
_
_
_
2HSO4,Br ,Cl ,SO4
_
_
_
_
IO3,F ,SCN ,NO2
_
0.2
_
H2PO4,ClO4
2+
Zincon+Cu
0.0
300
400
500
600
700
800
Wavelength (nm)
Figure S18. UV-vis spectra of zincon at the presence of different anions mixture(5.0×10-5 mol/L) in
water. The concentration of zincon was 5.0×10-5 mol/L and Cu2+ was 2.2×10-5 mol/L. The pH value
of the solution was about 9.1.
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0.8
A-A0 ( au) /λ463 nm
0.6
0.4
0.2
0.0
0
1
2
3
4
[CN-] (ppm)
Figure S19. Absorption difference at λ= 463 nm versus the concentration of CN- in water with the
concentrations of zincon and Cu2+ at 5.0×10-5 and 2.2×10-5 mol/L , respectively. The pH value of the
solution was about 8.2.
5
A(λ463nm)/A(λ600nm)
4
3
2
1
0
0
1
2
3
4
ppm
Figure S20. Absorption difference A(463nm)/A(600nm) versus the concentration of CN- in water
with the concentrations of zincon and Cu2+ at 5.0×10-5 and 2.2×10-5 mol/L , respectively. The pH
value of the solution was about 8.2.
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0.8
A-A0 ( au) /λ463 nm
0.6
0.4
0.2
0.0
0
1
2
3
4
[CN-] (ppm)
Figure S21. Absorption difference at λ= 463 nm versus the concentration of CN- in water with the
concentrations of zincon and Cu2+ at 5.0×10-5 and 2.2×10-5 mol/L , respectively. The pH value of the
solution was about 9.1.
5
A(λ463nm)/A(λ600nm)
4
3
2
1
0
0
1
2
3
4
ppm
Figure S22. Absorption difference A(463nm)/A(600nm) versus the concentration of CN- in water
with the concentrations of zincon and Cu2+ at 5.0×10-5 and 2.2×10-5 mol/L , respectively. The pH
value of the solution was about 9.1.
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