| Autor: |
Sahoo, Prangya P., Güneren, Alper, Hudec, Boris, Mikolášek, Miroslav, Nada, Ahmed, Precnerová, Magdaléna, Mičušík, Matej, Lenčéš, Zoltán, Nádaždy, Peter, Fröhlich, Karol |
| Zdroj: |
ACS Applied Nano Materials; 8/23/2024, Vol. 7 Issue 16, p18486-18498, 13p |
| Abstrakt: |
Silicon (Si) is a promising anode material due to its high theoretical capacity and abundant presence as the second most common element in the earth's crust. However, the formation of an unstable solid-electrolyte interphase (SEI) and significant volume expansion during lithiation result in structural degradation, leading to a decrease in the cycle life for Si-based anodes. This paper reports on the electrochemical performance of the silicon/graphite (Si/Gr) electrodes coated with nanometer-thick ZnO layers prepared by atomic layer deposition (ALD). In our study, ZnO layers were deposited using 5–40 ALD cycles on Si/Gr electrodes of ∼20 μm thickness. Electrochemical measurements such as galvanostatic charging/discharging at different C-rates and electrochemical impedance spectroscopy were performed utilizing the pristine and 5–40 ALD cycles of ZnO on Si/Gr electrodes in a half-cell configuration. The Si/Gr electrodes (pristine and ZnO-coated) were analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy (XPS) before and after electrochemical cell cycling. The ZnO-coated samples showed a better electrochemical rate performance than the uncoated pristine Si/Gr sample. The reversible conversion of the ZnO ALD films was demonstrated through dQ/dV plots and XPS analysis during (de)-lithiation. The ultrathin ZnO layers passivate the underlying Si/Gr electrodes, help in the formation of a stable SEI layer, and facilitate lithium-ion transport through the SEI layer. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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