Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (1)

Search Parameters:
Keywords = tubular graphite cones

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
21 pages, 32765 KiB  
Article
Sustainable Synthesis of Diamond-like Carbon and Giant Carbon Allotropes from Hyperbaric Methanol–Water Mixtures Through the Critical Point
by Mohamad E. Alabdulkarim, Vibhor Thapliyal and James L. Maxwell
J. Manuf. Mater. Process. 2024, 8(6), 286; https://doi.org/10.3390/jmmp8060286 - 9 Dec 2024
Cited by 2 | Viewed by 1310
Abstract
Freeform carbon fibres were 3D-printed from CH3OH:H2O mixtures using hyperbaric-pressure laser chemical vapour deposition (HP-LCVD). The experiment overlapped a region of known diamond growth, with the objective of depositing diamond-like carbon without the use of plasmas or hot filaments. [...] Read more.
Freeform carbon fibres were 3D-printed from CH3OH:H2O mixtures using hyperbaric-pressure laser chemical vapour deposition (HP-LCVD). The experiment overlapped a region of known diamond growth, with the objective of depositing diamond-like carbon without the use of plasmas or hot filaments. A high-pressure regime was investigated for the first time through the precursor’s critical point. Seventy-two C-fibres were grown from 13 different CH3OH:H2O mixtures at total pressures between 7.8 and 180 bar. Maximum steady-state axial growth rates of 14 µm/s were observed. Growth near the critical point was suppressed, ostensibly due to thermal diffusion and selective etching. In addition to nanostructured graphite, various carbon allotropes were synthesised at/within the outer surface of the fibres, including diamond-like carbon, graphite polyhedral crystal, and tubular graphite cones. Several allotropes were oversized compared to structures previously reported. Raman spectral pressure–temperature (P-T) maps and a pictorial P-T phase diagram were compiled over a broad range of process conditions. Trends in the Raman ID/IG and I2D/IG intensity ratios were observed and regions of optimal growth for specific allotropes were identified. It is intended that this work provide a basis for others in optimising the growth of specific carbon allotropes from methanol using HP-LCVD and similar CVD processes. Full article
Show Figures

Figure 1

Back to TopTop