A straightforward approach to electrodeposit tungsten

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poly(3,4-ethylenedioxythiophene) composites onto nanoporous gold for the hydrogen evolution reaction. Xinxin Xiaoa, Christian Engelbrektb, Minwei Zhangb, ...
Supplementary Interactive Plot Data (CSV)

A straightforward approach to electrodeposit tungsten disulfide / poly(3,4-ethylenedioxythiophene) composites onto nanoporous gold for the hydrogen evolution reaction Xinxin Xiaoa, Christian Engelbrektb, Minwei Zhangb, Zheshen Lic, Jens Ulstrupb, Jingdong Zhangb*, Pengchao Sia*

aKey

Laboratory for Liquid-Solid Structural Evolution and Processing of Materials,

Ministry of Education, School of Materials Science and Engineering, Shandong University, Jinan 250061, People's Republic of China bDepartment

of Chemistry, DTU Chemistry, Building 207, Kemitorvet, Technical

University of Denmark, DK 2800 Kongens Lyngby, Denmark cISA,

Department of Physics, Aarhus University, 8000, Aarhus, Denmark

*Corresponding author: Pengchao Si ([email protected]) and Jingdong Zhang ([email protected])

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Supplementary Figures and legends

Figure S1. SEM image of the bare NPG.

Figure S2. The relationship between EDOT/(NH4)2WS4 concentration ratio and yielded catalytic response obtained at an overpotential of 250 mV. 2

Note: The concentration of EDOT was fixed at 20 mM. Various concentrations of WS42- (10, 5, 2.5 and 1 mM) were used, leading to the ratio of: 2, 4, 8 and 20. 20 mM LiClO4 and 1.0 mM PEG are used as the supporting electrolyte and surfactant to enhance the solubility of EDOT in aqueous solutions. 15 cycles of potential scanning were used to obtain the modified NPG electrodes. It’s clear that a moderate ratio of 8 (2.5 mM WS42-) led to the highest catalytic current density. This is believed to be the result of a tradeoff between the amount of active WS2 and electron transfer routes brought by the PEDOT matrix.

Figure S3. Cyclic voltammograms of NPG (solid line) and planar gold electrode (dotted line).

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Figure S4. XPS spectra of PEDOT/WS2: survey spectrum.

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Figure S5. XPS spectra of PEDOT/WS2: O 1s region.

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Figure S6. FTIR spectrum of samples with different components.

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Figure S7. Nyquist (A) and Bode plots (B) showing EIS responses of NPG/PEDOT/WS2 electrode at various HER potentials in 0.5 M H2SO4.

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Fig. S8. Current stability of NPG/PEDOT/WS2 electrode at -0.25 V vs. RHE in 0.5 M H2SO4 (noises were due to the generation and collapse of hydrogen bubbles).

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Captions for Movies Movie NPG-PEDOT A movie showing TEM imaging of NPG/PEDOT interface. After 3 seconds, the PEDOT layer was burnt out under the electron irradiation. The video frequency is 30.3 fps (frames per second). Movie NPG-WS2 A movie showing TEM imaging of NPG/WS2 interface. The coating layer was stable under the electron irradiation. The video frequency is 30.3 fps. Movie NPG-PEDOT-WS2 A movie showing TEM imaging of NPG/PEDOT/WS2 composite, which was resistant to electron irradiation. The video frequency is 30.3 fps.

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