Amorphous Silicon Nanoparticles and Silicon Nanoglasses from Ab Initio Simulations


BOLAT S., Durandurdu M.

Silicon, 2024 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2024
  • Doi Number: 10.1007/s12633-024-03005-9
  • Journal Name: Silicon
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Compendex, INSPEC
  • Keywords: Amorphous, High pressure, Nanoglass, Nanoparticle, Silicon
  • Karadeniz Technical University Affiliated: Yes

Abstract

The structural and electrical characteristics of spherical amorphous silicon nanoparticles (Si-NPs) with radii ranging from 9 to 15 Å, and silicon nanoglasses (Si-NGs) formed by compressing identical-sized Si-NPs, are being investigated for the first-time using ab initio simulations. Analysis reveals predominantly fourfold coordination within Si-NPs, accompanied by noticeable coordination defects. The prevalence of fourfold coordination increases with increasing Si-NP size. Si-NGs, while exhibiting similar dominant fourfold coordination, possess a small fraction of coordination defects (5–8%) primarily concentrated at the interfaces of compressed Si-NPs. Si-NGs are found to have a more open structure compared to amorphous Si. This structural variation, along with observed distortions within Si-NGs, is hypothesized to contribute to a significant narrowing of their band gaps relative to amorphous Si.