Recent Advances in Ultrathin Two-Dimensional Nanomaterials

Chemical Reviews, Journal Year: 2017, Volume and Issue: 117(9), P. 6225 - 6331

Published: March 17, 2017

Since the discovery of mechanically exfoliated graphene in 2004, research on ultrathin two-dimensional (2D) nanomaterials has grown exponentially fields condensed matter physics, material science, chemistry, and nanotechnology. Highlighting their compelling physical, chemical, electronic, optical properties, as well various potential applications, this Review, we summarize state-of-art progress 2D with a particular emphasis recent advances. First, introduce unique advances nanomaterials, followed by description composition crystal structures. The assortments synthetic methods are then summarized, including insights advantages limitations, alongside some recommendations suitable characterization techniques. We also discuss detail utilization these for wide ranges applications among electronics/optoelectronics, electrocatalysis, batteries, supercapacitors, solar cells, photocatalysis, sensing platforms. Finally, challenges outlooks promising field featured basis its current development.

Language: Английский

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Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds: Synthetic Routes, Properties, and Applications

Chemical Reviews, Journal Year: 2016, Volume and Issue: 117(4), P. 3479 - 3716

Published: June 3, 2016

Two-dimensionally extended, polycyclic heteroaromatic molecules (heterocyclic nanographenes) are a highly versatile class of organic materials, applicable as functional chromophores and semiconductors. In this Review, we discuss the rich chemistry large heteroaromatics, focusing on their synthesis, electronic properties, applications in materials science. This Review summarizes historical development current state art rapidly expanding field research, which has become one key exploration areas modern heterocyclic chemistry.

Language: Английский

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Oxidative C–H/C–H Coupling Reactions between Two (Hetero)arenes

Chemical Reviews, Journal Year: 2017, Volume and Issue: 117(13), P. 8787 - 8863

Published: Jan. 13, 2017

Transition metal-mediated C-H bond activation and functionalization represent one of the most straightforward powerful tools in modern organic synthetic chemistry. Bi(hetero)aryls are privileged π-conjugated structural cores biologically active molecules, functional materials, ligands, intermediates. The oxidative C-H/C-H coupling reactions between two (hetero)arenes through 2-fold offer a valuable opportunity for rapid assembly diverse bi(hetero)aryls further exploitation their applications pharmaceutical material sciences. This review provides comprehensive overview fundamentals transition metal-mediated/catalyzed (hetero)arenes. substrate scope, limitation, reaction mechanism, regioselectivity, chemoselectivity, as well related control strategies these discussed. Additionally, established methods synthesis natural products new materials exemplified. In last section, short introduction on oxidant- or Lewis acid-mediated Ar-H/Ar-H is presented, considering that it very method construction biaryl units polycylic arenes.

Language: Английский

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Exploration of pyrazine-embedded antiaromatic polycyclic hydrocarbons generated by solution and on-surface azomethine ylide homocoupling

Nature Communications, Journal Year: 2017, Volume and Issue: 8(1)

Published: Nov. 29, 2017

Nanographenes, namely polycyclic aromatic hydrocarbons (PAHs) with nanoscale dimensions (>1 nm), are atomically precise cutouts from graphene. They represent prime models to enhance the scope of chemical and physical properties graphene through structural modulation functionalization. Defined nitrogen doping in nanographenes is particularly attractive due its potential for increasing number π-electrons, possibility introducing localized antiaromatic ring elements. Herein we present azomethine ylide homocoupling as a strategy afford internally nitrogen-doped, non-planar PAH solution planar nanographene on surfaces, central pyrazine rings. Localized antiaromaticity indicated by optical absorption spectroscopy conjunction theoretical calculations. Our opens up methods chemically tailoring nanographenes, modified dopants.

Language: Английский

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Full-Color, Narrowband, and High-Efficiency Electroluminescence from Boron and Carbazole Embedded Polycyclic Heteroaromatics

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(46), P. 19468 - 19472

Published: Nov. 5, 2020

Herein, we demonstrate that the strategic implementation of electron-accepting tricoordinate boron and electron-donating carbazole subunits into polycyclic aromatic hydrocarbons (PAHs) produces a family attractive full-color luminophores can emit narrowband efficient thermally activated delayed fluorescence (TADF). A versatile modular design for these boron- carbazole-embedded PAHs facilitate systematic modulation their photophysical optoelectronic properties. Organic light-emitting diodes utilize as TADF emitters electroluminescence from blue to red, achieving high maximum external quantum efficiencies 29.3%, 31.8%, 22.0% blue, green, respectively.

Language: Английский

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Interface-Assisted Synthesis of 2D Materials: Trend and Challenges

Chemical Reviews, Journal Year: 2018, Volume and Issue: 118(13), P. 6189 - 6235

Published: June 18, 2018

The discovery of graphene one decade ago has triggered enormous interest in developing two-dimensional materials (2DMs)—that is 2D allotropes various elements or compounds (consisting two more covalently bonded elements) molecular frameworks with periodic structures. At present, synthesis strategies have been exploited to produce 2DMs, such as top-down exfoliation and bottom-up chemical vapor deposition solution methods. In this review article, we will highlight the interfacial roles toward controlled inorganic organic 2DMs varied structural features. We summarize state-of-the-art progress on address their advancements structural, morphological, crystalline control by direction arrangement molecules precursors at a confined space. First, provide an overview interfaces introduce advantages uniqueness for followed brief classification achieved synthesis. Next, currently developed combined representative are summarized, including description method details, corresponding features, insights into limitations methods, along some recommendable characterization methods understanding assembly crystal growth 2DMs. After that, discuss several classes emerging particular emphasis strategies. Note not be categorized separately due fact that number articles covered synthesis, structure, processing, applications. Finally, challenges perspectives provided regarding future development interface-assisted diverse functional control.

Language: Английский

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A Review on Design Strategies for Carbon Based Metal Oxides and Sulfides Nanocomposites for High Performance Li and Na Ion Battery Anodes

Advanced Energy Materials, Journal Year: 2016, Volume and Issue: 7(9)

Published: Dec. 22, 2016

Carbon‐oxide and carbon‐sulfide nanocomposites have attracted tremendous interest as the anode materials for Li Na ion batteries. Such composites are fascinating they often show synergistic effect compared to their singular components. Carbon nanomaterials used matrix due high conductivity, tensile strength, chemical stability under battery condition. Metal oxides sulfides active material fillers because of large capacity. Numerous works shown that by taking one step further into fabricating with rational structure design, much better performance can be achieved. The present review aims discuss development carbon‐based nanocomposite anodes in both batteries authors introduce individual components composites, i.e., carbon matrices (e.g., nanotube, graphene) metal oxides/sulfides; followed evaluating how advanced nanostructures benefit from when put together. Particular attention is placed on strategies employed such examples yolk–shell structure, layered‐by‐layered composite comprising or more matrices. Lastly, conclude highlighting challenges still persist perspective develop technologies.

Language: Английский

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Structurally Constrained Boron-, Nitrogen-, Silicon-, and Phosphorus-Centered Polycyclic π-Conjugated Systems

Chemical Reviews, Journal Year: 2019, Volume and Issue: 119(14), P. 8291 - 8331

Published: March 12, 2019

Incorporation of main group elements into the π-conjugated frameworks is a sophisticated strategy to alter fundamental nature parent conjugated π-systems, giving rise attractive electronic and photophysical properties that are otherwise inaccessible with classic carbon- or metal-based materials. Out all heterocycles, those structurally constrained by tethered aryl substituents surrounding center deserve great deal attention because not only do they commonly possess maximum efficiency π-conjugation intermolecular interaction, but also enjoy remarkable thermal morphological stabilities especially crucial for solid-state performances. In certain cases, elucidation behavior such compounds may additionally provide sufficient perspective toward graphene materials doped elements, which widely considered as potential next-generation optoelectronic this review, we will specifically focus on historical developments polycyclic π-electron systems particularly boron, nitrogen, silicon, phosphorus atoms annulated directly systems.

Language: Английский

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Structurally uniform and atomically precise carbon nanostructures

Nature Reviews Materials, Journal Year: 2016, Volume and Issue: 1(1)

Published: Jan. 11, 2016

Language: Английский

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On‐Surface Synthesis of Atomically Precise Graphene Nanoribbons

Advanced Materials, Journal Year: 2016, Volume and Issue: 28(29), P. 6222 - 6231

Published: Feb. 12, 2016

The surface-assisted polymerization and cyclodehydrogenation of specifically designed organic precursors provides a route toward atomically precise graphene nanoribbons, which promises to combine the outstanding electronic properties with bandgap that is sufficiently large for room-temperature digital-logic applications. Starting from basic concepts behind on-surface synthesis approach, this report covers progress made in understanding different reaction steps, synthesizing nanoribbons various widths edge structures, characterizing their properties, ending an outlook on challenges still lie ahead.

Language: Английский

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