Investigating catechol adsorption to the ZnO (101̄0) surface with and without an oxygen vacancies using the DFT-D2...

Area of Science:

• Surface Science
• Materials Chemistry
• Computational Chemistry

Background:

• Surface functionalization is key for tailoring electronic and adsorption properties of materials.
• Chemisorption offers robust functionalization, requiring molecular-level understanding for stability and structure.
• Designing catalysts, sensors, and functional materials relies on insights into adsorption phenomena.

Purpose of the Study:

• To investigate catechol adsorption on pristine ZnO and oxygen-vacancy containing ZnO (ZnOv) (101̄0) surfaces.
• To elucidate adsorption mechanisms using Density Functional Theory (DFT) and Bader charge analysis.
• To provide a molecular-level understanding of molecule-surface interactions for advanced material design.

Main Methods:

• Detailed Density Functional Theory (DFT) calculations were employed.
• Bader charge analysis and electronic structure calculations were performed.
• Experimental adsorption kinetics on ZnO nanoparticles were used for benchmarking.

Main Results:

• Catechol exhibits strong chemisorption on pristine ZnO surfaces, with a Zn-O bond length of 1.95 Å.
• Weaker chemisorption was observed for fully protonated catechol on ZnOv surfaces (2.31 Å bond length).
• Charge transfer from the surface to catechol was detected on both surfaces, confirmed by electronic structure changes.

Conclusions:

• Catechol chemisorption on ZnO surfaces is confirmed, with implications for functional material design.
• Oxygen vacancies in ZnO surfaces significantly influence and weaken catechol adsorption.
• The combined theoretical and experimental approach enhances understanding of molecule-ZnO interactions.