Multiscale Self-Assembly of Silicon Quantum Dots into an Anisotropic Three-Dimensional Random Network
NANO LETTERS, vol.16, pp.1942-1948, 2016 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 16
- Publication Date: 2016
- Doi Number: 10.1021/acs.nanolett.5b05158
- Journal Name: NANO LETTERS
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Page Numbers: pp.1942-1948
- Keywords: Si, random network, hierarchical, multiscale, self-assembly, stochastic deposition, NANOSTRUCTURES, GROWTH, PHOTOVOLTAICS, NANOPARTICLES, NANOCRYSTALS, PHOTONICS, NANOSCALE, NANOWIRES
- Open Archive Collection: AVESIS Open Access Collection
- Middle East Technical University Affiliated: Yes
Abstract
Multiscale self-assembly is ubiquitous in nature but its deliberate use to synthesize multifunctional three-dimensional materials remains rare, partly due to the notoriously difficult problem of controlling topology from atomic to macroscopic scales to obtain intended material properties. Here, we propose a simple, modular, noncolloidal methodology that is based on exploiting universality in stochastic growth dynamics and driving the growth process under far-from-equilibrium conditions toward a preplanned structure. As proof of principle, we demonstrate a confined-but connected solid structure, comprising an anisotropic random network of silicon quantum-dots that hierarchically self-assembles from the atomic to the microscopic scales. First, quantum-dots form to subsequently interconnect without inflating their diameters to form a random network, and this network then grows in a preferential direction to form undulated and branching nanowire-like structures. This specific topology simultaneously achieves two scale-dependent features, which were previously thought to be mutually exclusive: good electrical conduction on the microscale and a bandgap tunable over a range of energies on the nanoscale.