Electronic Structure and External Electric Field Modulation of Polyethylene/Graphene Interface.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Polymer nanocomposites show potential for electrostatic shielding.
• The carrier transport mechanisms at polymer-nanofiller interfaces are not well understood.

Purpose of the Study:

• Investigate the structural and electronic properties of polyethylene/graphene (PE/G) interfaces.
• Understand carrier transport mechanisms under electric fields for improved electrostatic shielding.

Main Methods:

• First-principle calculations were used to study PE/G interfaces (type-H and type-A).
• Analysis of bandgaps, charge distribution, Fermi level shifts, and Schottky barrier heights (SBH) under varying electric fields.

Main Results:

• Bandgaps opened at the Dirac point for both H-type (128.6 meV) and A-type (67.8 meV) PE/G interfaces.
• Electron-rich graphene and hole-rich polyethylene layers observed, forming p-type Schottky contacts.
• Electric fields can tune SBH, converting Schottky contacts to Ohmic contacts; H-type requires a lower field than A-type.

Conclusions:

• The findings offer insights into the conduction mechanisms of graphene-based polymer composites.
• Understanding these mechanisms is key to optimizing their performance as electrostatic shielding materials.