Synthesis of a ZnO nanorod/CVD graphene composite for simultaneous sensing

of dihydroxybenzene isomers

Can Ge a, Hongji Li b, *, Mingji Li a, *, Cuiping Li a, Xiaoguo Wu a, Baohe Yang a

a Tianjin Key Laboratory of Film Electronic and Communicate Devices, School of Electronics

Information Engineering, Tianjin University of Technology, Tianjin 300384, P.R. China

b Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry

and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, P.R. China

*Corresponding authors.

E-mail: hongjili@yeah.net (Hongji Li); limingji@163.com (Mingji Li)

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Fig. S1- Photos of graphene/Ta and ZnO/graphene electrodes. Inset: CVD graphene/Ta sheet.

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Fig. S2- SEM image of the surface of a Ta substrate in the H2 plasma without CH4.

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Fig. S3- HRTEM image of the products.

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Fig. S4- HRTEM image of the CVD graphene sheets.

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Scheme S1. Mechanism of redox reactions of HQ, CC and RC on the ZnO/graphene/Ta electrode.

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Table S1. Performance comparison of the fabricated electrode for HQ, CC and RC

detection versus other electrodes.

Electrodes Linear range (μM) LOD (μM) Method Ref.HQ CC RC HQ CC RC

Graphene-chitosan/GCE

1-300 1-400 1-550 0.75 0.75

0.75

DPV;Selective detection

[7]

MWCNT-SH@Au-graphene/GCE

54.5-1250.5

11.0-126.0 43.5-778.5

4.17 1.0 7.8 DPV;Selective detection

[8]

MWCNTs/CDs/MWCNTs/GCE

1-200 4-200 1-400 0.07 0.06

0.15

DPV;Selective detection

[9]

WS2-graphene/GCE 1-100 1-100 1-100 0.1 0.2 0.1 DPV;Simultaneous detection

[10]

Polyaniline/MnO2/GCE 0.2-100 0.2-100 0.2-100 0.13 0.16

0.09

DPV;Simultaneous detection

[11]

SWCNT/GCE 0.4-1040-100

0.4-1040-100

0.4-1040-100

0.12 0.26

0.3 2.5th-order differential voltammetry

[49]

MWCNT/GCE 2-100 2-100 5-80 0.6 0.6 1 LSV;Selective detection

[50]

ZnO/graphene/Ta 0-70 0-80 0-700 0.1 0.2 1 CV; Simultaneous detection

This

work

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Fig. S5- CV curves for interferences including 0.4 mM CaCl2, 0.4 mM CuSO4, 0.4 mM KCl, 0.4 mM

Mg(NO3)2, 0.4 mM Na2HPO4, 0.4 mM NaH2PO4, 0.4 mM Ni(NO3)2, 0.4 mM Zn(NO3)2, 0.1 mM

aniline, and 0.1 mM phenol in the presence of 0.1 mM HQ, 0.1 mM CC and 0.1 mM RC.

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Table S2.

The response of the ZnO/graphene/Ta electrode to the interferences.

InterferencesResponse with respect to HQ (%)

Response with respect to CC (%)

Response with respect to RC (%)

CaCl2 2.76% 2.49% 3.01%

CuSO4 3.71% 0.41% 3.27%

KCl 3.02% 1.76% 3.41%

Mg(NO3)2 4.10% 3.93% 3.41%

Na2HPO4 4.45% 1.44% 1.96%

NaH2PO4 4.73% 1.32% 3.77%

Ni(NO3)2 4.55% 2.08% 2.84%

Zn(NO3)2 2.77% 2.06% 4.07%

Aniline 1.40% 4.00% 4.93%

Phenol 0.01% 4.34% 3.65%

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Fig. S6- CVs of as-prepared ZnO nanorod/graphene electrode in 0.1 M PBS (pH 7.0) containing 0.1 mM HQ, 0.1 mM CC and 0.1 mM RC. (a) The CV responses at one electrode by successive measurements. (b) CV data at different electrodes.

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