Tunneling conductivity in anisotropic nanofiber composites: a percolation-based model

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Nanofiber-based composites are crucial for advanced electronic applications.
• Understanding their electrical conductivity is essential for material design.
• Anisotropy in nanoparticle conductance influences overall composite properties.

Purpose of the Study:

• To develop a model for conductivity in nanofiber composites using CPA and percolation theory.
• To investigate the impact of nanoparticle orientation and clustering on conductivity.
• To analyze the role of orientational order parameter variations.

Main Methods:

• Integration of the critical path approximation (CPA) with lattice-based percolation.
• Incorporation of anisotropy in tunneling-based conductance based on nanoparticle orientation.
• Examination of conductivity as a function of volume fraction, clustering, and orientational order parameters.

Main Results:

• Conductivity is sensitive to volume fraction, clustering, and orientational order.
• A strong dependence of conductivity on the standard deviation of the orientational order parameter was observed.
• This dependence persists even when the mean order parameter is constant.

Conclusions:

• The standard deviation of nanoparticle orientation significantly impacts composite conductivity.
• CPA and percolation modeling provide insights into complex composite behavior.
• Precise control over nanoparticle alignment is critical for optimizing conductivity.