The present invention relates to a graphene nanoribbon, comprising a repeating unit which comprises at least one modification, wherein the modification is selected from a heteroatomic substitution, a vacancy, a sp.sup.3 hybridization, a Stone-Wales defect, an inverse Stone-Wales defect, a hexagonal sp.sup.2 hybridized carbon network ring size modification, and any combination thereof.

The Present teachings provide, in part, methods of separating two-dimensional nanomaterials by atomic layer thickness. In certain embodiments, the present teachings provide methods of generating graphene nanomaterials having a controlled number of atomic layer(s).

The present invention concerns ortho-Terphenyls of general formula (I); wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently selected from the group consisting of H; CN; NO.sub.2; and saturated, unsaturated or aromatic C.sub.1-C.sub.40 hydrocarbon residues, which can be substituted 1- to 5-fold with F, CI, OH, NH.sub.2, CN and/or NO.sub.2, and wherein one or more CH.sub.2-groups can be replaced by O, NH, S, C(O)O, OC(O) and/or C(O); and X and Y are the same or different, and selected from the group consisting of F, CI, Br, I, and OTf (trifluoromethanesulfonate); and their use for the preparation of graphene nanoribbons as well as a process for the preparation of graphene nanoribbons from said ortho-Terphenyls.

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Embodiments of the present invention provide methods of preparing functionalized graphene nanoribbons by (1) exposing a plurality of carbon nanotubes to an alkali metal source in the presence of an aprotic solvent, wherein the exposing opens the carbon nanotubes; and (2) exposing the opened carbon nanotubes to an electrophile to form functionalized graphene nanoribbons. Such methods may also include a step of exposing the opened carbon nanotubes to a protic solvent in order to quench any reactive species on the opened carbon nanotubes. Further embodiments of the present invention pertain to graphene nanoribbons formed by the methods of the present invention. Additional embodiments of the present invention pertain to nanocomposites and fibers containing the aforementioned graphene nanoribbons.

Provided are graphene nanoribbons with controlled zig-zag edge and cove edge configuration and methods for preparing such graphene nanoribbons. The nanoribbons are selected from the following formulae.

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A preparation method of a graphene nanoribbon on h-BN, comprising: 1) forming a h-BN groove template with a nano ribbon-shaped groove structure on the h-BN by adopting a metal catalysis etching method; 2) growing a graphene nanoribbon in the h-BN groove template by adopting a chemical vapor deposition method. In the present invention, a CVD method is adopted to directly prepare a morphology controllable graphene nanoribbon on the h-BN, which helps to solve the long-term critical problem that the graphene is difficult to nucleate and grow on an insulating substrate, and to avoid the series of problems introduced by the complicated processes of the transferring of the graphene and the subsequent clipping manufacturing for a nanoribbon and the like.

Provided are graphene nanoribbons (GNRs), methods of making GNRs, and uses of the GNRs. The methods can provide control over GNR parameters such as, for example, length, width, and edge composition (e.g., edge functional groups). The methods are based on a metal catalyzed cycloaddition reaction at the carbon-carbon triple bonds of a poly(phenylene ethynylene) polymer. The GNRs can be used in devices such a microelectronic devices.

Provided are a method for preparing a nanotube array, a nanotube array and a device. The method includes: preparing a double-layer two-dimensional material with a relative angle of lattice orientations, which is used as a template; determining the chiral parameters of nanotubes to be prepared corresponding to the relative angle of the lattice orientations of the double-layer two-dimensional material, determining a nanoribbon orientation and a nanoribbon width according to the determined chiral parameters, determining the inter-nanoribbon spacing according to the density of the nanotubes to be prepared and the nanoribbon width, and etching the double-layer two-dimensional material according to the determined nanoribbon orientation, nanoribbon width and inter-nanoribbon spacing to obtain a nanoribbon array of the double-layer two-dimensional material; and performing thermal excitation treatment on the obtained nanoribbon array of the double-layer two-dimensional material to obtain a nanotube array. The present disclosure can prepare a nanotube array with controllable density, orientation and chirality.

This invention in one aspect relates to a method of synthesizing a self-assembled mixed-dimensional heterostructure including 2D metallic borophene and 1D semiconducting armchair-oriented graphene nanoribbons (aGNRs). The method includes depositing boron on a substrate to grow borophene thereon at a substrate temperature in an ultrahigh vacuum (UHV) chamber; sequentially depositing 4,4-dibromo-p-terphenyl on the borophene grown substrate at room temperature in the UHV chamber to form a composite structure; and controlling multi-step on-surface coupling reactions of the composite structure to self-assemble a borophene/graphene nanoribbon mixed-dimensional heterostructure. The borophene/aGNR lateral heterointerfaces are structurally and electronically abrupt, thus demonstrating atomically well-defined metal-semiconductor heterojunctions.