XANES absorption spectra of penta-graphene and penta-SiC2 with different terminations: a computational study

TL;DR

This computational study explores the XANES spectra of penta-graphene and penta-SiC2 in various states to aid their experimental identification and future optical device applications.

Contribution

It provides the first ab initio analysis of XANES spectra for these novel 2D pentagonal materials across different terminations and substitutions.

Findings

XANES spectra vary with surface terminations and substitutions.

Identification of spectral features for experimental detection.

Foundation for engineering optical properties in 2D materials.

Abstract

In recent research, penta-graphene and penta-SiC2 have emerged as innovative 2D materials consisting exclusively of pentagons. However, there is still a significant gap in the theoretical characterization of these materials, which hinders progress in their synthesis and potential technological applications. This study aims to close this gap by investigating the X-ray absorption near-edge spectroscopy (XANES) of these materials through ab initio calculations. In particular, we analyze the XANES spectra of penta-graphene in its pristine, hydrogenated, and hydroxylated states, and we investigate the effects of substitution by a single silicon in both penta-graphene and pentagraphane. In addition, we calculate the XANES spectra for pristine and hydrogenated penta-SiC2. This work sets the stage for the possible identification of penta-graphene and penta-SiC2 phases by X-ray spectroscopy at the experimental level and lays the foundation for the future engineering of the absorption properties of these materials in optical devices.