The interactions of nitrogen dioxide with graphene-stabilized Rh clusters: a DFT study

Area of Science:

• Surface Science
• Materials Chemistry
• Computational Chemistry

Background:

• Rhodium nanoparticles are crucial catalysts.
• Graphene is a promising support material.
• Understanding gas-molecule interactions on surfaces is vital for catalysis and sensing.

Purpose of the Study:

• To investigate the adsorption of nitrogen dioxide (NO2) on rhodium (Rh) nanoparticles supported by graphene.
• To determine the stability and morphology of Rh nanoparticles (Rhx, x=1, 3, 10, 20) on graphene.
• To analyze the binding energies and effects on graphene properties.

Main Methods:

• First-principles molecular dynamics simulations using the Car-Parrinello scheme.
• Modeling of Rh nanoparticles of varying sizes (x=1, 3, 10, 20) supported on graphene.
• Calculation of adsorption energies and analysis of structural properties.

Main Results:

• Identified metastable, flat Rh nanoparticle structures anchored to the graphene substrate.
• Observed strong binding of NO2 molecules to Rh clusters via both nitrogen and oxygen atoms.
• Adsorption energies for NO2 on Rh nanoparticles ranged from 60-70 kcal/mol.
• Investigated the influence of NO2 adsorption on the electronic properties of graphene.

Conclusions:

• Metastable Rh nanoparticle configurations on graphene exhibit significant binding affinity for NO2.
• The strong interaction suggests potential applications in catalysis and gas sensing.
• The study provides fundamental insights into molecule-surface interactions on supported metal nanoparticles.