Raman spectroscopy revealing noble gas adsorption on single-walled carbon nanotube bundles
Summary¶
This page tracks an uncorrected proof PDF (papers/Cunha_Carbon_2017_proof.pdf) for a Carbon article investigating argon and xenon adsorption on single-walled carbon nanotube (SWCNT) bundles using low-temperature Raman spectroscopy combined with ReaxFF-based modeling. Bundles deposited on transmission electron microscopy grids are exposed to noble gases at 20 K, where condensed adsorbates populate external groove sites (the interstitial channels between tubes in a bundle) and outer bundle surfaces. The abstract reports substantial blueshifts of the radial breathing mode (RBM), G-band, and G′/2D features, interpreted as a solidified adsorbate shell that applies an effective hydrostatic pressure to the nanotube lattice, mechanically coupling to the measured phonons. The authors highlight that Ar and Xe produce almost the same frequency shifts, arguing that the bundle–gas interactions are nearly identical in strength within the experimental resolution, consistent with physisorption-dominated noble-gas probes.
Methods¶
Same experimental + ReaxFF design as the version-of-record article (DOI 10.1016/j.carbon.2017.11.017): Raman on SWCNT bundles with Ar/Xe at 20 K, plus ReaxFF modeling of adsorption-site occupancy and mechanical coupling to phonon shifts. This repo pdf_path points to an uncorrected proof—use 2017cunha-carbon-127-2-raman-spectroscopy for the journal-layout PDF when reconciling numbers.
MD protocol details (code, ensemble, timestep, thermostat/barostat, duration, supercell definitions) match the VOR Carbon Methods; they are not transcribed from the indexed proof excerpt on this duplicate-route page.
MD blueprint honesty (proof route). Reactive molecular dynamics with ReaxFF on PBC bundle models mirrors the VOR. LAMMPS is the usual MD engine—confirm in the journal PDF. NVT/NPT/NVE, timestep, thermostat, barostat/pressure, and equilibration/production times (ps/ns) are N/A from the proof excerpt—copy from 2017cunha-carbon-127-2-raman-spectroscopy’s Methods source.
Findings¶
Blueshifts of RBM/G/2D upon noble-gas condensation; Ar and Xe give nearly identical shift patterns, consistent with physisorption-dominated coupling. Interpretation: shifts reflect mechanical loading from a solidified adsorbate shell more than strong electronic doping (supported by linewidth/intensity behavior in the manuscript). Treat this slug as a duplicate PDF route; detailed simulation–experiment comparisons live in the final Carbon PDF. Comparisons: experimental Raman trends for Ar vs Xe are the primary comparator; modeling supports physisorption interpretations. Sensitivity: temperature (20 K dosing) controls adsorption state. Limitations: proof PDF may omit final figure quality; see ## Limitations.
Limitations¶
Proof PDF (extraction_quality: partial): pagination, metadata, and figures may differ from the VOR; prefer 2017cunha-carbon-127-2-raman-spectroscopy for curation-backed numbers.
Relevance to group¶
Alternate manifest entry for van Duin/Terrones-adjacent nanotube adsorption work.
Citations and evidence anchors¶
- DOI:
https://doi.org/10.1016/j.carbon.2017.11.017(papers/Cunha_Carbon_2017_proof.pdf).