Pseudo-topotactic conversion of carbon nanotubes to T-carbon nanowires under picosecond laser irradiation in methanol

Abstract

Pseudo-topotactic conversion of carbon nanotubes into one-dimensional carbon nanowires is a challenging but feasible path to obtain desired diameters and morphologies. Here, a previously predicted but experimentally unobserved carbon allotrope, T-carbon, has been produced from pseudo-topotactic conversion of a multi-walled carbon nanotube suspension in methanol by picosecond pulsed-laser irradiation. The as-grown T-carbon nanowires have the same diameter distribution as pristine carbon nanotubes, and have been characterized by high-resolution transmission electron microscopy, fast Fourier transform, electron energy loss, ultraviolet–visible, and photoluminescence spectroscopies to possess a diamond-like lattice, where each carbon is replaced by a carbon tetrahedron, and a lattice constant of 7.80 Å. The change in entropy from carbon nanotubes to T-carbon reveals the phase transformation to be first order in nature. The computed electronic band structures and projected density of states are in good agreement with the optical absorption and photoluminescence spectra of the T-carbon nanowires.

Mechanical properties of γ-graphyne nanotubes

“…In recent years, graphene 1 and its allotropes, such as graphyne 2 and T-carbon, 3 have gained tremendous attention due to their unusual mechanical, thermal and optical properties.…”

A New Metallic Porous Carbon Phase tP‐C12 with an sp2‐sp3 Bonding Network: A First‐Principle Calculation

“…Inspired by the successful synthesis of T carbon obtained from carbon nanotubes, and recent research on 4‐ and 8‐membered carbon rings in carbon nanostructures, including the experimental synthesize of graphene‐like nanoribbon and the predicted structure evolution from (4,4) SWCNT to 3D (4,4) carbon, we propose that a possible route to access this material by the defection of 4‐ and 8‐membered carbon rings of nanotube structures. Influenced by driving force, those adjacent nanotubes defect and the connection bonds between two nanotubes could form, resulting in the formation of the tP−C12 phase.…”

“…Among all the proposed carbon allotropes, the porous T carbon, which was first theoretically predicted in 2011, was recently experimentally synthesized in 2017 . The T‐carbon nanowire was grown via pseudo‐topotactic conversion during the picosecond pulsed‐laser irradiation of a multi‐walled carbon nanotube suspension . The breakthrough of the new identified three‐dimensional carbon crystals expect diamond and lonsdaleite extends the carbon science and encourages people to make more efforts to new carbon allotropes.…”

Exploring T-carbon for energy applications

“…T-carbon has recently been synthesized in experiment ( Figure 2H) from a pseudo-topotactic conversion of multi-walled carbon nanotube (MWCNTs) suspended in methanol under picosecond pulsed-laser irradiation 8 . Firstly, MWCNTs (length: ∼100-200 nm; diameter: ∼10-20 nm) are prepared by chemical vapor deposition (CVD) and subsequent processing.…”