Depletion-interaction effects on the tunneling conductivity of nanorod suspensions

Nigro, B.; Grimaldi, C.; Miller, Mark A.; Ryser, P.; Schilling, T.

Abstract

We study by simulation and theory how the addition of insulating spherical particles affects the conductivity of fluids of conducting rods, modeled by spherocylinders. The electrical connections are implemented as tunneling processes, leading to a more detailed and realistic description than a discontinuous percolation approach. We find that the spheres enhance the tunneling conductivity for a given concentration of rods and that the enhancement increases with rod concentration into the regime where the conducting network is well established. By reformulating the network of rods using a critical path analysis, we quantify the effect of depletion-induced attraction between the rods due to the spheres. Furthermore, we show that our conductivity data are quantitatively reproduced by an effective-medium approximation, which explicitly relates the system tunneling conductance to the structure of the rod-sphere fluid.

Citation

Nigro, B., Grimaldi, C., Miller, M. A., Ryser, P., & Schilling, T. (2013). Depletion-interaction effects on the tunneling conductivity of nanorod suspensions. Physical review E: Statistical, nonlinear, and soft matter physics, 88(4), Article 042140. https://doi.org/10.1103/physreve.88.042140

• Journal Article Type: Article
• Publication Date: Oct 25, 2013
• Deposit Date: Sep 25, 2014
• Publicly Available Date: Sep 26, 2014
• Journal: Physical review . E, Statistical, nonlinear, and soft matter physics
• Print ISSN: 1539-3755
• Electronic ISSN: 1550-2376
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 88
• Issue: 4
• Article Number: 042140
• DOI: https://doi.org/10.1103/physreve.88.042140
• Public URL: https://durham-repository.worktribe.com/output/1445085