Nonradiative Excited-State Decay via Conical Intersection in Graphene Nanostructures

Area of Science:

• Materials Science
• Quantum Chemistry
• Nanotechnology

Background:

• Chemical functionalization influences graphene nanomaterial luminescence.
• Epoxide groups are potential luminescence quenchers in graphene.

Purpose of the Study:

• Investigate the role of epoxide groups in graphene luminescence quenching.
• Elucidate the mechanism of nonradiative decay in graphene epoxide nanostructures.

Main Methods:

• Nonadiabatic excited-state dynamics simulations.
• Analysis of conical intersection pathways.

Main Results:

• Identified fast (within 300 fs) nonradiative decay from the S1 to S0 state.
• Conical intersection formation induced by C-O bond breaking in the epoxide moiety.
• Epoxide groups facilitate excited electron-hole recombination.

Conclusions:

• Epoxide groups act as key sites for nonradiative de-excitation in graphene nanomaterials.
• Conical intersections are crucial for understanding luminescence quenching.
• Nonadiabatic dynamics simulations are effective for studying graphene photophysics.