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Abstract Nanoporous graphene (NPG) can exhibit a uniform electronic band gap and rationally‐engineered emergent electronic properties, promising for electronic devices such as field‐effect transistors (FETs), when synthesized with atomic precision. Bottom‐up, on‐surface synthetic approaches developed for graphene nanoribbons (GNRs) now provide the necessary atomic precision in NPG formation to access these desirable properties. However, the potential of bottom‐up synthesized NPG for electronic devices has remained largely unexplored to date. Here, FETs based on bottom‐up synthesized chevron‐type NPG (C‐NPG), consisting of ordered arrays of nanopores defined by laterally connected chevron GNRs, are demonstrated. C‐NPG FETs show excellent switching performance with on–off ratios exceeding 104, which are tightly linked to the structural quality of C‐NPG. The devices operate as p‐type transistors in the air, while n‐type transport is observed when measured under vacuum, which is associated with reversible adsorption of gases or moisture. Theoretical analysis of charge transport in C‐NPG is also performed through electronic structure and transport calculations, which reveal strong conductance anisotropy effects in C‐NPG. The present study provides important insights into the design of high‐performance graphene‐based electronic devices where ballistic conductance and conduction anisotropy are achieved, which could be used in logic applications, and ultra‐sensitive sensors for chemical or biological detection.
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Liquid-phase bottom-up synthesis of graphene nanoribbons
Graphene nanoribbons (GNRs) – an emerging family of carbon-based semiconductors – can be precisely synthesised from small molecules such as benzene derivatives through bottom-up approaches. This review outlines a summary of the development of bottom-up synthesis of GNRs in liquid phase. The strategies are classified based on edge structures and widths of the materials, which are the crucial factors for properties of GNRs. In addition, views on challenges in the field and the future outlook are also provided.
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- Award ID(s):
- 1707399
- PAR ID:
- 10295093
- Date Published:
- Journal Name:
- Materials Chemistry Frontiers
- Volume:
- 4
- Issue:
- 1
- ISSN:
- 2052-1537
- Page Range / eLocation ID:
- 29 to 45
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9qm00519f
