Molecular-level investigation of the adsorption mechanisms of thiazolidinediones on Cu2O(111) surface: a first-principles DFT study

We have employed first principles DFT calculation with van der Waals (vdW) corrections to investigate the adsorption mechanism of thiazolidine-2,4-dione (TZD) substituted by 4-methylbenzylidene (MTZD) at 5-position and by an additional allyl group (ATZD) at 3-position on copper oxide surface (Cu2O(111)). Parallel configurations were found the most energetically stable geometries. The adsorption binding energy magnitudes predicted that ATZD outperformed MTZD by -0.11 eV. Our calculations indicated that O and S atoms of thiazolidine-2,4-dione nucleus significantly enhanced the chemical bonding of ATZD and MTZD with Cu2O(111) surface. Hydrogen bond interactions between Lewis base site at unsaturated O atom above the copper surface and TZD molecules are contributing to the stability of TZD molecules on Cu2O(111) surface. The adsorption induced-work function of different TZD adsorption configurations decreased from 4.563 eV (Cu2O(111)) to 4.114-4.373 eV due to electron transport between TZD molecules and Cu2O(111). The analysis of electronic properties of TZDs adsorption geometries revealed strong charge transfer and redistribution at the interface of TZDs-Cu2O(111), strengthening the stability of molecules on copper oxide surface. These theoretical insights would pave the way for further in-depth investigations into TZD-Copper interactions and provide valuable information for an optimized design of copper corrosion inhibitors.