Behavior of implanted Xe, Kr and Ar in nanodiamond and thin graphene stacks: experiment and modeling

TL;DR

This study investigates how heavy noble gases like Xe, Kr, and Ar behave when implanted in nanodiamonds and graphene stacks, using experiments and computational modeling to understand defect formation and layer distortion.

Contribution

It combines experimental X-ray absorption spectroscopy with computational modeling to elucidate noble gas behavior and defect sites in nanodiamonds and graphene layers.

Findings

Xe prefers vacancy sites in nanodiamonds.

Noble gases cause distortion and bulges in graphene layers.

Lower energy for ions in flat graphene compared to curved regions.

Abstract

Implantation and subsequent behaviour of heavy noble gases (Ar, Kr, Xe) in few-layer graphene sheets and in nanodiamonds is studied both using computational methods and experimentally using X-ray absorption spectroscopy. X-ray absorption spectroscopy provides substantial support for the Xe-vacancy (Xe-V) defect as a main site for Xe in nanodiamond. It is shown that noble gases in thin graphene stacks distort the layers, forming bulges. The energy of an ion placed in between flat graphene sheets is notably lower than in domains with high curvature. However, if the ion is trapped in the curved domain, considerable additional energy is required to displace it.