Lead (Pb) interfacing with epitaxial graphene
| Autor: | Rositsa Yakimova, G. Reza Yazdi, Tihomir Iakimov, Mikhail Vagin, Ivan Shtepliuk, Ivan Gueorguiev Ivanov |
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| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Materials science
Scanning electron microscope Nucleation General Physics and Astronomy 02 engineering and technology 010402 general chemistry 01 natural sciences law.invention Metal chemistry.chemical_compound symbols.namesake law Silicon carbide Physical and Theoretical Chemistry Electroplating Graphene 021001 nanoscience & nanotechnology Condensed Matter Physics 0104 chemical sciences chemistry Chemical physics visual_art Electrode symbols visual_art.visual_art_medium 0210 nano-technology Raman spectroscopy Den kondenserade materiens fysik |
| Popis: | Here, we report the electrochemical deposition of lead (Pb) as a model metal on epitaxial graphene fabricated on silicon carbide (Gr/SiC). The kinetics of electrodeposition and morphological characteristics of the deposits were evaluated by complementary electrochemical, physical and computational methods. The use of Gr/SiC as an electrode allowed the tracking of lead-associated redox conversions. The analysis of current transients passed during the deposition revealed an instantaneous nucleation mechanism controlled by convergent mass transport on the nuclei locally randomly distributed on epitaxial graphene. This key observation of the deposit topology was confirmed by low values of the experimentally-estimated apparent diffusion coefficient, Raman spectroscopy and scanning electron microscopy (SEM) studies. First principles calculations showed that the nucleation of Pb clusters on the graphene surface leads to weakening of the interaction strength of the metal-graphene complex, and only spatially separated Pb adatoms adsorbed on bridge and/or edge-plane sites can affect the vibrational properties of graphene. We expect that the lead adatoms can merge in large metallic clusters only at defect sites that reinforce the metal-graphene interactions. Our findings provide valuable insights into both heavy metal ion electrochemical analysis and metal electroplating on graphene interfaces that are important for designing effective detectors of toxic heavy metals. Funding Agencies|VR grant [621-2014-5805]; SSF [SSF GMT14-0077, SSF RMA15-0024]; Angpanneforeningens Forskningsstiftelse [16-541] |
| Databáze: | OpenAIRE |
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