Combinatorial approach for the synthesis of precursors for chirality-controlled synthesis of SWCNTs

Abstract

We report a theoretical approach for synthesis of precursors for the rational synthesis of chirality-pure single-walled carbon nanotubes (SWCNT) by surface-assisted method. The presented combinatorial strategy in combination with the massselective deposition technique provides a simple access to precursors for SWCNT of various chiralities, including large diameter tubes. The synthetic strategy provides a simple access to the robust SWCNT precursors "preprogrammed" for 54 different chiralities, starting from just four simple cyclic ketones. The molecules exhibit a rigid and fully fused structure which is expected to be important for a highly efficient conversion to ultra-short SWCNTs and for high yield of the respective isomer-pure tubes. The advantages and limitations of the approach for the preparative production of chirality pure SWCNTs are discussed.

Combinatorial design of molecular seeds for chirality-controlled synthesis of single-walled carbon nanotubes

“…Accepting that only IPR (Isolated Pentagon Rule, stating that all pentagons have to be completely surrounded by hexagons in order to form less strained system 41 ,) structures are stable, all possible SWCNT-caps (for a certain chirality) can be derived by constructive enumeration 42 . Further, the suitable precursor structures can be found retrosynthetically from the respective SWCNT end-caps by formal unrolling to the quasi-planar PAH (polycyclic aromatic hydrocarbon) 43,44 . The last one can be obtained by multi-step organic synthesis.…”

“…4e) already contain several completed SWCNT-belts which are exclusively composed of hexagons (with no pentagons on the periphery). Such ultra-short SWCNTs possess enhanced stability and are expected to be very effective for the initiation of the nanotube growth under CVD condition 29,35,44 .…”

Towards Rational Synthesis of Non‐IPR Fullerenes Via Tandem Cyclodehydrofluorination of Fluoroarene‐Based Precursors

“…In general, the presented synthetic strategy can be extended to the synthesis of various highly interesting non‐IPR solids. In particular, the synthesis of non‐IPR hemispherical bowls is of high interest for the controlled growth of small‐dimer chirality‐pure carbon nanotubes . In general, the presented approach could provide facile access to this elusive class of carbon allotropes in the near future.…”

Synthesis of Rationally Halogenated Buckybowls by Chemoselective Aromatic C−F Bond Activation

“…As a result, the controllable functionalization of the buckybowl system still remains a challenge, thus hampering further development in this field. Appropriate functionalized buckybowls are important starting materials for further derivatization and key building blocks for the rational synthesis of fullerenes, nanotubes, and other related carbon‐based nanostructures by a bottom‐up strategy . In this respect, halogenated, and in particular brominated, bowls appear to be the most important derivatives .…”