Coverage-dependent adsorption of atomic sulfur on Fe(110): a DFT study

Area of Science:

• Surface Science
• Materials Science
• Computational Chemistry

Background:

• Understanding adsorbate-adsorbate interactions is crucial for predicting surface properties.
• Atomic sulfur adsorption on iron surfaces is relevant to catalysis and materials science.

Purpose of the Study:

• To investigate the influence of adsorbate-adsorbate interactions on Fe(110) surface properties.
• To examine sulfur adsorption at different coverages (1/2 and 1 monolayer) on Fe(110).

Main Methods:

• Density Functional Theory (DFT) calculations.
• Analysis of binding energy, work function change, adsorption geometry, charge density, magnetic properties, and density of states.
• Comparison with previous studies at lower coverages.

Main Results:

• Sulfur forms polar covalent bonds with the Fe(110) surface.
• At low coverages, S-Fe bonding is dominant.
• At high coverages (c(2x2) and p(1x1)), S-S interactions become significant as sulfur atoms approach each other.

Conclusions:

• Adsorbate-adsorbate interactions play a key role in modifying surface properties.
• The nature of chemical bonding shifts from S-Fe to S-S dominated with increasing sulfur coverage.
• DFT provides valuable insights into the complex behavior of adsorbates on metal surfaces.