Electronic Supplementary Information

Pt74Ag26 nanoparticle-decorated Ultrathin MoS2 Nanosheets as

Novel Peroxidase Mimics for Highly Selective Colorimetric

Detection of H2O2 and Glucose

Shuangfei Cai, Qiusen Han, Cui Qi, Zheng Lian, Xinghang Jia, Rong Yang* and

Chen Wang*

CAS Key Lab for Biological Effects of Nanomaterials and Nanosafety, National

Center for Nanoscience and Technology, Beijing 100190, People’s Republic of China.

* Corresponding authors: yangr@nanoctr.cn; wangch@nanoctr.cn

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Electronic Supplementary Material (ESI) for Nanoscale.This journal is © The Royal Society of Chemistry 2016

Contents

Figure S1. Representative AFM, SEM and HRTEM images, XRD pattern and FT-IR

spectra of the as-prepared MoS2-PAH.

Figure S2. XPS survey spectrum, high-resolution peak-fitting XPS spectra of Mo 3d

and S 2p regions as well as Zeta potential of the as-prepared MoS2-PAH.

Figure S3. Representative TEM images of the as-prepared MoS2-Pt74Ag26 with

different magnifications and size distribution histogram.

Figure S4. Representative TEM images of the as-prepared MoS2-Pt and different

MoS2-PtAg hybrids with different Pt/Ag feeding molar ratios.

Figure S5. Representative HAADF-STEM image of the MoS2-Pt74Ag26 nanohybrids,

elemental maps for Pt and Ag, overlapped elemental maps of Pt and Ag as well as

EDX line-scanning profile across a Pt-Ag NP.

Figure S6. UV-Vis spectra and corresponding photographs of different solutions.

Figure S7. Representative TEM image and size distribution histogram of the as-

prepared Pt73Ag27 NPs.

Figure S8. Relative activity of different materials, long-term stability and reusability

after repeated cycles of H2O2 sensing of MoS2-Pt74Ag26.

Figure S9. Representative TEM image and size distribution histogram of the recycled

nanohybrids.

Figure S10. Dependence of the catalytic activity of MoS2-Pt74Ag26 on temperature,

pH and H2O2 concentration.

Figure S11. The effect of MoS2-Pt74Ag26 on the formation of hydroxyl radical with

terephthalic acid (TA) as a fluorescence probe.

Figure S12. ESR spectra for the oxidation of TMB catalyzed by MoS2-Pt74Ag26.

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0 200 400 600 800 10000.00.30.60.91.21.51.8

Horizontal Position (nm)

Heig

ht (n

m)

A B0.25 μm

a

1 μm

b

c

5 nm 1 nm

d

0.315 nm

4000 3500 3000 2500 2000 1500 1000

Tran

smitt

ance

(a. u

.)

Wavenumber (cm-1)

MoS2

PAH MoS2-PAH

f

10 20 30 40 50 60 70 80 90

(0010)

(118)

(108)

(008)

(110)(105)

(006)

(103)

(102)

(101)

(100)

(004)

Inte

nsity

(a. u

.)

2 Theta (degree)

(002)

e

Figure S1. Representative AFM, SEM and HRTEM images, XRD pattern and FT-IR

spectra of the as-prepared MoS2-PAH. (a) AFM image (inset: lineprofile of A-B line

indicated in Figure S1a); (b) SEM image; (c) HRTEM image (inset: corresponding

fast Fourier transform (FTT) pattern); (d) magnified HRTEM image indicated in

Figure S1c; (e) XRD pattern and (f) FT-IR spectra.

3

1400 1200 1000 800 600 400 200 0

Cl 2pN 1s

Mo 3d

C 1sIn

tens

ity (a

. u.)

Binding Energy (eV)

O 1s

S 2p

a

234 232 230 228 226 224

Mo 3d5/2

Inte

nsity

(a. u

.)

Binding Energy (eV)

S 2s

Mo 3d3/2

b

d

2 4 6 8 10 12-20-10

0102030405060

Zeta

pot

entia

l (m

V)

pH

c

167 166 165 164 163 162 161 160 159 158

S 2p3/2

Inte

nsity

(a. u

.)

Binding Energy (eV)

S 2p1/2

Figure S2. (a) XPS survey spectrum, (b) high-resolution peak-fitting XPS spectra of

Mo 3d and (c) S 2p regions as well as (d) Zeta potential of the as-prepared MoS2-PAH.

4

a b

c d

e

10 11 12 13 14 150

5

10

15

20

25

Freq

uenc

y (%

)

Size of Pt74Ag26 NPs (nm)

Mean: 12.8f

Figure S3. (a-e) Different magnifications of TEM images of the as-prepared MoS2-

Pt74Ag26, (f) size distribution histogram.

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Figure S4. Representative TEM images of the as-prepared MoS2-Pt (a) and different

MoS2-PtAg hybrids with Pt/Ag feeding molar ratios of 3 : 1 (b), 1 : 1 (c) and 1 : 3 (d),

respectively.

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0 5 10 15 20 25 30 35 40

Coun

ts (a

. u.)

Position (nm)

Pt Ag

a

c

b

d

e

Figure S5. (a) Representative HAADF-STEM image of the MoS2-Pt74Ag26

nanohybrids, elemental maps for (b) Pt and (c) Ag, (d) overlapped elemental maps of

Pt and Ag, (e) EDX line-scanning profile across a Pt-Ag NP (inset) indicated in

Figure S5a.

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Figure S6. UV-Vis spectra of material solution (a), TMB solution (b), TMB-H2O2

solution (c) and TMB-H2O2-material solution (d) in 0.2 M acetate buffer (pH 4.0).

Inset: photographs of different solutions.

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5050 nmnm

a b

7 8 9 10 11 12 13 14 15 16 17 1805

101520253035

Freq

uenc

y (%

)

Size (nm)

Mean: 11.8

Figure S7. (a) Representative TEM image and (b) size distribution histogram of the

as-prepared Pt73Ag27 NPs.

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Figure S8. Relative activity of different materials (a), MoS2-PtAg with different

Pt/Ag feeding ratios (b), the long-term stability (c) and the reusability (d) after

repeated cycles of H2O2 sensing of MoS2-Pt74Ag26. The maximum point was set 100

%.

10

a

7 8 9 10 11 12 13 14 15 16 17 18 19 20048

12162024283236

Freq

uenc

y (%

)

Size (nm)

Mean: 12.2b

Figure S9. (a) Representative TEM image and (b) size distribution histogram of the

recycled nanohybrids.

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Figure S10. Dependence of the catalytic activity of MoS2-Pt74Ag26 on (a) temperature,

(b) pH and (c) H2O2 concentration. The maximum point in each curve was set 100 %.

12

330 360 390 420 450 480 510 540 570 600

Inte

nsity

(a. u

.)

Wavelength (nm)

a

c

Figure S11. The effect of MoS2-PtAg on the formation of hydroxyl radical with

terephthalic acid (TA) as a fluorescence probe. (a) TA/MoS2-Pt74Ag26; (b) TA/H2O2;

(c) TA/MoS2-Pt74Ag26/H2O2.

13

319 320 321 322 323 324 325 326

d

c (5 min)b (0 min)

Inte

nsity

(a. u

.)

Magnetic field (mT)

a

Figure S12. ESR spectra for the oxidation of TMB catalyzed by MoS2-PtAg: (a)

buffer/TMB/H2O2; (b-c) buffer/H2O2/MoS2-PtAg for 0 min and 5 min; (d)

buffer/H2O2/MoS2-PtAg/TMB.

14