Electronic Properties and Structure of Silicene on Cu and Ni Substrates

Materials (Basel). 2022 May 28;15(11):3863. doi: 10.3390/ma15113863.

Abstract

Silicene, together with copper or nickel, is the main component of electrodes for solar cells, lithium-ion batteries (LIB) and new-generation supercapacitors. The aim of this work was to study the electronic properties and geometric structure of "silicene-Ni" and "silicene-Cu" systems intended for use as LIB electrodes. The densities of electronic states, band structures, adhesion energies and interatomic distances in the silicene-(Cu, Ni) systems were determined by ab initio calculations. Silicene on a copper substrate exhibited temperature stability in the temperature range from 200 to 800 K, while on a nickel substrate, the structure of silicene was rearranged. Adsorption energies and bond lengths in the "silicene-Cu" system were calculated in the range of Li/Si ratios from 0.125 to 0.5. The formation of the Li2 isomer during the adsorption of lithium in a ratio to silicon of 0.375 and 0.5 was observed. Silicene was found to remain stable when placed on a copper substrate coated with a single layer of nickel. The charge redistribution caused by the addition of a nickel intermediate layer between silicene and a copper substrate was studied.

Keywords: adhesion; lithium; silicene; structure; substrate.

Grants and funding

This research was funded as the frame of the scientific theme of Institute of high-temperature electrochemistry UB RAS, number FUME-2022-0007, registration number 122020100288-8.