Tailoring highly conductive graphene nanoribbons from small polycyclic aromatic hydrocarbons: a computational study

Area of Science:

• Molecular electronics
• Materials science
• Condensed matter physics

Background:

• Pyrene derivatives with thiol substitutions are explored as molecular interconnects.
• Understanding charge transport in nanoscale systems is crucial for molecular electronics.

Purpose of the Study:

• To model and analyze charge transport in pyrene-based molecular devices.
• To investigate the electronic properties of pyrene-derived graphene nanoribbons.

Main Methods:

• Density functional theory (DFT) with and without self-interaction correction.
• Non-equilibrium Green's function (NEGF) method for charge transport modeling.
• Analysis of bias voltage and length effects on conductance.

Main Results:

• Tetra-substituted pyrene with dual thiol groups exhibits high, bias-independent conductance.
• Zigzag-edged graphene nanoribbons show length and voltage-independent conductance due to perfect transmission.
• Armchair-edged nanoribbons display semiconducting behavior with exponential conductance decay.

Conclusions:

• Pyrene-based molecular interconnects offer promising high-conductance pathways.
• Zigzag and armchair graphene nanoribbons present distinct charge transport characteristics for device applications.