Desorption kinetics of Bi adsorption on Ni(100) revealed through temperature-programmed desorption spectra: A kinetic Monte Carlo study

Abstract

In this study, key features of the temperature-programmed desorption spectra obtained during adsorption and subsequent desorption of Bi adsorbates on Ni(100) from 800 K to 1400 K were analyzed using kinetic Monte Carlo simulations. In contrast with prior work that proposed a coexistence of first order and second order desorption kinetics to account for the two peaks observed at 1000 K and 1280 K, with the 1000 K peak appearing only at relatively high pre-adsorbed Bi coverages of 0.96 ML and higher, we have demonstrated that first-order desorption, which is heavily influenced by a repulsive adsorbate lateral interaction among adsorbates, might be a more appropriate explanation and should account for both peaks. Furthermore, we have shown that the absence of lateral interaction as well as the presence of an attractive lateral interaction cannot replicate the observed shift towards lower peak temperatures with increasing pre-adsorbed Bi coverage.