Computational investigation of a promising Si–Cu anode material

Abstract

The lack of suitable anode materials is a limiting factor in the creation of a new generation of lithium-ion batteries.

Computational Study of Lithium Intercalation in Silicene Channels on a Carbon Substrate after Nuclear Transmutation Doping

“…The remaining hg values were separated from each other by a distance of 0.1 nm. The lithium atoms in the channel with the gap hg = 0.75 nm could move quite freely along the channels located on the metal (Ag, Al, and Cu) substrates [5][6][7]35]. In the present work, the initial distance between the lower silicene sheet and the graphite substrate was 0.222 nm and corresponded to a similar value determined using the DFT calculations in Reference [36].…”

“…In the present work, the initial distance between the lower silicene sheet and the graphite substrate was 0.222 nm and corresponded to a similar value determined using the DFT calculations in Reference [36]. The channel did not have material sidewalls but was surrounded by an artificial force barrier, making it difficult for atoms to escape through the side and back surfaces [7]. The model we used corresponded with electrodes in a lithium-ion battery being separated by a solid electrolyte.…”

“…The value h g = 0.24 nm was determined in the DFT calculations as a gap in two-layer free-standing silicene [34]. The gap h g = 0.75 nm was used to study the intercalation/deintercalation of lithium in a silicene channel on metal substrates [5][6][7]. The remaining h g values were separated from each other by a distance of 0.1 nm.…”

“…Through the input (frontal surface), Li + ions were periodically introduced into the channel at an interval of 1 ps. Ions were introduced one after another and were "drawn" into the channel due to the applied electric field having a strength of 10 4 V / m. After 1 ps, the Li + ion entering the channel turned into a lithium atom [7], which subsequently did not "feel" the presence of the electric field. In other words, the intercalation was simulated in the form of ions entering the silicene channel from a solid electrolyte, as is shown in Figure 2.…”

“…Thin films of silicon and (in particular) silicene are the most promising anode materials for lithium-ion batteries [5][6][7]. The advantage of their use in electrochemical devices is that they allow for the maintenance of a high theoretical electrode capacity (4200 mAh/g), which characterizes the intercalation of lithium in bulk silicon.…”