The world of two-dimensional carbides and nitrides (MXenes)

Science, Год журнала: 2021, Номер 372(6547)

Опубликована: Июнь 10, 2021

A family of thin materials Two-dimensional (2D) have attracted interest because the unusual properties that emerge in these confined structures. There is a growing 2D metal carbides and nitrides known as MXenes contain an odd number layers which metals (M) sandwich carbon or nitrogen (X) layers. VahidMohammadi et al. reviewed progress synthesizing this library materials. Mixed-metal combinations can be used, well range surface terminations, making it possible to tune properties. However, there are still challenges improving synthesis methods developing techniques scaled up. Science , abf1581, issue p. eabf1581

Язык: Английский

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Ten Years of Progress in the Synthesis and Development of MXenes

Advanced Materials, Год журнала: 2021, Номер 33(39)

Опубликована: Авг. 16, 2021

Abstract Since their discovery in 2011, the number of 2D transition metal carbides and nitrides (MXenes) has steadily increased. Currently more than 40 MXene compositions exist. The ultimate is far greater time they may develop into largest family materials known. MXenes’ unique properties, such as metal‐like electrical conductivity reaching ≈20 000 S cm −1 , render them quite useful a large applications, including energy storage, optoelectronic, biomedical, communications, environmental. papers patents published been growing quickly. first generation synthesized using selective etching layers from MAX phases, layered carbonitrides hydrofluoric acid. then, multiple synthesis approaches have developed, mixture fluoride salts various acids, non‐aqueous etchants, halogens, molten salts, allowing for new MXenes with better control over surface chemistries. Herein, brief historical overview 10 years research perspective on future development are provided. fact that production readily scalable aqueous environments, high yields bodes well commercialization.

Язык: Английский

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Advances in the Synthesis of 2D MXenes

Advanced Materials, Год журнала: 2021, Номер 33(39)

Опубликована: Авг. 22, 2021

Abstract 2D transition metal carbides, nitrides, and carbonitrides, also known as MXenes, are versatile materials due to their adjustable structure rich surface chemistry. The physical chemical diversity has recognized MXenes a potential material with wide spectrum of application domains. Since the discovery in 2011, variety synthetic routes been proposed advancement toward large‐scale preparing methods for MXene nanosheets derivative products. Herein, critical synthesis aspects operating conditions that influence characteristics discussed detail. emerging etching including HF methods, situ HF‐forming electrochemical alkali molten salt well delamination strategies discussed. Considering future developments practical applications, antioxidation summarized. In summary, generalized overview protocols an outlook current challenges promising technologies preparation stable storage is provided.

Язык: Английский

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Fundamentals of MXene synthesis

Nature Synthesis, Год журнала: 2022, Номер 1(8), С. 601 - 614

Опубликована: Авг. 1, 2022

Язык: Английский

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A Review on MXene Synthesis, Stability, and Photocatalytic Applications

ACS Nano, Год журнала: 2022, Номер 16(9), С. 13370 - 13429

Опубликована: Сен. 12, 2022

Photocatalytic water splitting, CO2 reduction, and pollutant degradation have emerged as promising strategies to remedy the existing environmental energy crises. However, grafting of expensive less abundant noble-metal cocatalysts on photocatalyst materials is a mandatory practice achieve enhanced photocatalytic performance owing ability extract electrons efficiently from enable rapid/enhanced catalytic reaction. Hence, developing highly efficient, inexpensive, noble-metal-free composed earth-abundant elements considered noteworthy step toward considering photocatalysis more economical strategy. Recently, MXenes (two-dimensional (2D) transition-metal carbides, nitrides, carbonitrides) shown huge potential alternatives for cocatalysts. several excellent properties, including atomically thin 2D morphology, metallic electrical conductivity, hydrophilic surface, high specific surface area. In addition, they exhibit Gibbs free intermediate H atom adsorption close zero than that commercial Pt-based cocatalyst, Fermi level position above H2 generation potential, an capture activate molecules. Therefore, there growing interest in MXene-based various events. this review, we focus recent advances synthesis with 0D morphologies, stability MXenes, photocatalysts evolution, degradation. The challenges possible future directions enhance are also discussed.

Язык: Английский

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MXene‐Copper/Cobalt Hybrids via Lewis Acidic Molten Salts Etching for High Performance Symmetric Supercapacitors

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(48), С. 25318 - 25322

Опубликована: Сен. 29, 2021

MXenes have attracted great interests as supercapacitors due to their metallic conductivity, high density, and hydrophilic nature. Herein we report Ti3 C2 -Cu/Co hybrids via molten salt etching in which the existence of metal atoms interactions with MXene surficial O were elucidated by XAFS for first time. The electrochemical investigation -Cu electrode demonstrated pseudocapacitive contribution Cu a splendid specific capacitance 885.0 F g-1 at 0.5 A 1.0 M H2 SO4 . Symmetric supercapacitor -Cu//Ti3 was operating voltage 1.6 V, areal 290.5 mF cm-2 1 mA , stability over 10 000 cycles. It delivered an energy density 103.3 μWh power 0.8 mW based on pouch fabricated. provides deeper insights into mechanism strategies designing MXene-based materials storage.

Язык: Английский

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Recent Advances in Oxidation Stable Chemistry of 2D MXenes

Advanced Materials, Год журнала: 2021, Номер 34(13)

Опубликована: Ноя. 24, 2021

Abstract As an emerging star of 2D nanomaterials, transition metal carbides and nitrides, named MXenes, present a large potential in various research areas owing to their intrinsic multilayer structure intriguing physico‐chemical properties. However, the fabrication application functional MXene‐based devices still remain challenging as they are prone oxidative degradation under ambient environment. Within this review, preparation methods MXenes focusing on recent investigations thermal structure–stability relationships inert, oxidizing, aqueous environments systematically introduced. Moreover, key factors that affect oxidation such as, atmosphere, temperature, composition, microstructure, environment, reviewed. Based different scenarios, strategies for avoiding or delaying proposed encourage utilization complicated environments, especially at high temperature. Furthermore, chemistry MXene‐derived oxides is analyzed, which can offer perspectives further design novel composites with unique structures being preserved.

Язык: Английский

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Ambient‐Stable Two‐Dimensional Titanium Carbide (MXene) Enabled by Iodine Etching

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(16), С. 8689 - 8693

Опубликована: Янв. 23, 2021

MXene (e.g., Ti3 C2 ) represents an important class of two-dimensional (2D) materials owing to its unique metallic conductivity and tunable surface chemistry. However, the mainstream synthetic methods rely on chemical etching MAX powders AlC2 using hazardous HF or alike, leading sheets with fluorine termination poor ambient stability in colloidal dispersions. Here, we demonstrate a fluoride-free, iodine (I2 assisted route for preparing 2D (Ti3 Tx , T=O, OH) oxygen-rich terminal groups intact lattice structure. More than 71 % are thinner 5 nm average size 1.8 μm. They present excellent thin-film 1250 S cm-1 great water at least 2 weeks. abundant oxygen electrode supercapacitors, delivering high gravimetric capacitance 293 F g-1 scan rate 1 mV s-1 superior those made from fluoride-based etchants (<290 ). Our strategy provides promising pathway facile sustainable production highly stable materials.

Язык: Английский

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Recent advances of MXenes as electrocatalysts for hydrogen evolution reaction

npj 2D Materials and Applications, Год журнала: 2021, Номер 5(1)

Опубликована: Сен. 9, 2021

Abstract MXenes, an emerging two-dimensional (2D) transition metal carbides, nitrides and carbonitrides, have exhibited great potential as electrocatalysts for hydrogen evolution reaction (HER) due to the excellent characters, including structural chemical stability, superior electrical conductivity, large active surface area. In this comprehensive study, firstly, preparation advances of MXenes are systematically summarized. Then, representative applications MXenes-based HER introduced, from experimental theoretical aspects. Thirdly, strategies improving catalytic activity demonstrated, such optimizing sites by termination modification metal-atom doping, increasing fabricating various nanostructures. Finally, existing challenges new opportunities also elucidated. This paper provides reference future development efficient production through water-splitting technology.

Язык: Английский

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MXenes for Energy Harvesting

Advanced Materials, Год журнала: 2022, Номер 34(21)

Опубликована: Янв. 20, 2022

Abstract Energy harvesting modules play an increasingly important role in the development of autonomous self‐powered microelectronic devices. MXenes (i.e., 2D transition metal carbide/nitride) have recently emerged as promising candidates for energy applications due to their excellent electronic conductivity, large specific surface area, and tunable properties. Herein, a perspective on using harvest from various sources environment is presented. First, characteristics that facilitate capturing are systematically introduced preparation strategies derived nanostructures tailored toward such summarized. Subsequently, mechanism different (e.g., solar energy, thermoelectric triboelectric piezoelectric salinity‐gradient electrokinetic ultrasound humidity energy) discussed. Then, recent progress MXene‐based harvesting, well applications, introduced. Finally, opinions existing challenges future directions nanostructure

Язык: Английский

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