Electronegativity-dependent Pt anchoring and molecule adsorption for graphene-based supported Pt single atom

Area of Science:

• Surface Science and Catalysis
• Materials Science
• Computational Chemistry

Background:

• Investigating single-atom catalysts (SACs) on graphene supports is crucial for efficient chemical reactions.
• Understanding the role of defects, such as carbon vacancies and nitrogen doping, in modulating catalyst properties is essential.
• The adsorption of formaldehyde (HCHO) and oxygen (O2) on supported platinum (Pt) single atoms is critical for various catalytic applications.

Purpose of the Study:

• To elucidate the impact of carbon vacancies and nitrogen doping on graphene supports for Pt single-atom catalysts.
• To determine how these modifications influence the adsorption of HCHO and O2.
• To identify optimal configurations for enhanced catalytic activity.

Main Methods:

• Density Functional Theory (DFT) calculations were employed using the VASP code.
• Projector Augmented Wave (PAW) method and Generalized Gradient Approximation (GGA) with Perdew-Burke-Ernzerhof (PBE) functionals were utilized.
• Device Studio software was used for specific computational procedures.

Main Results:

• Electronegativity of the graphene support, tuned by vacancies and N-doping, is key for Pt anchoring and adsorbate adsorption.
• Pyrrolic-N doping and specific vacancy/doping concentrations (e.g., 1V-Gr, 1N-Gr, 2N-Gr) showed optimal electronegativity.
• These optimized supports facilitated stronger Pt anchoring and more favorable adsorption of HCHO and O2 compared to pristine graphene.

Conclusions:

• The study demonstrates that controlled C vacancies and N-doping in graphene can significantly enhance Pt SACs.
• Suitable tuning of graphene's electronic properties is vital for optimizing both Pt-support interaction and adsorbate binding.
• Pyridinic-N, 1V-Gr, 1N-Gr, and 2N-Gr are promising supports for HCHO and O2 adsorption applications.