Assembly mechanism of surface-functionalized nanocubes
Brian Hyun-Jong Lee1, Gaurav Arya1
1Department of Mechanical Engineering and Material Science, Duke University, Durham, NC 27708, USA. gaurav.arya@duke.edu.
Nanoscale
|February 28, 2022
Summary
Self-assembling nanocubes with grafted molecules exhibit complex pathways. Understanding these energy landscapes and assembly mechanisms is key to engineering uniform nanostructures.
Area of Science:
- Nanomaterials Science
- Computational Chemistry
- Surface Science
Background:
- Faceted nanoparticles are building blocks for advanced nanomaterials.
- Surface functionalization controls nanoparticle assembly distance and orientation.
Purpose of the Study:
- To computationally investigate the assembly mechanism of nanocubes grafted with short-chain molecules.
- To understand the role of energy landscapes and pathways in nanoparticle self-assembly.
Main Methods:
- Monte Carlo simulations to compute interaction free energy landscapes.
- Dijkstra algorithm to determine minimum free energy pathways.
- Analysis of nanocube configurations during assembly.
Main Results:
- Nanocube assembly pathways are rugged, with multiple energy barriers and metastable states.
- Assembly is dominated by sliding motions, with local dissociation, lineal separation, and rolling.
- Energy barrier heights depend on interaction strength, surface roughness, and graft repulsion.
Conclusions:
- Nanocube assembly configuration depends on both the minimum free energy state and the assembly pathway.
- Guidelines for engineering assembly pathways can aid in achieving uniform nanostructures.
- This study provides insights into the self-assembly of faceted nanoparticles.
