Energy-saving hydrogen production by chlorine-free hybrid seawater splitting coupling hydrazine degradation

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Июль 7, 2021

Abstract Seawater electrolysis represents a potential solution to grid-scale production of carbon-neutral hydrogen energy without reliance on freshwater. However, it is challenged by high costs and detrimental chlorine chemistry in complex chemical environments. Here we demonstrate chlorine-free hybrid seawater splitting coupling hydrazine degradation. It yields at rate 9.2 mol h –1 g cat NiCo/MXene-based electrodes with low electricity expense 2.75 kWh per m 3 H 2 500 mA cm –2 48% lower equivalent input relative commercial alkaline water electrolysis. Chlorine electrochemistry avoided cell voltages anode protection regardless Cl – crossover. This electrolyzer meanwhile enables fast degradation ~3 ppb residual. Self-powered realized integrating low-voltage direct fuel cells or solar cells. These findings enable further opportunities for efficient conversion ocean resources while removing harmful pollutants.

Язык: Английский

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Flexible MXene‐Based Composites for Wearable Devices

Advanced Functional Materials, Год журнала: 2021, Номер 31(22)

Опубликована: Март 8, 2021

Abstract In recent decades, flexible and wearable devices have been extensively investigated due to their promising applications in portable mobile electronics human motion monitoring. MXene, a novel growing family of 2D nanomaterials, demonstrates superiorities such as outstanding electrical conductivity, abundant terminal groups, unique layered‐structure, large surface area, hydrophilicity, making it be potential candidate material for devices. Numerous pioneering works are devoted develop MXene‐based composites with various functions designed structures. Therefore, the latest progress is summarized this review, focusing on preparation strategies, working mechanisms, performances, sensors, supercapacitors, electromagnetic interference shielding materials. Moreover, current challenges future outlooks also discussed.

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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Flexible and Waterproof 2D/1D/0D Construction of MXene-Based Nanocomposites for Electromagnetic Wave Absorption, EMI Shielding, and Photothermal Conversion

Nano-Micro Letters, Год журнала: 2021, Номер 13(1)

Опубликована: Июнь 25, 2021

High-performance electromagnetic wave absorption and interference (EMI) shielding materials with multifunctional characters have attracted extensive scientific technological interest, but they remain a huge challenge. Here, we reported an electrostatic assembly approach for fabricating 2D/1D/0D construction of Ti3C2Tx/carbon nanotubes/Co nanoparticles (Ti3C2Tx/CNTs/Co) nanocomposites excellent absorption, EMI efficiency, flexibility, hydrophobicity, photothermal conversion performance. As expected, strong reflection loss -85.8 dB ultrathin thickness 1.4 mm were achieved. Meanwhile, the high efficiency reached 110.1 dB. The performances originated from charge carriers, electric/magnetic dipole polarization, interfacial natural resonance, multiple internal reflections. Moreover, thin layer polydimethylsiloxane rendered hydrophilic hierarchical Ti3C2Tx/CNTs/Co hydrophobic, which can prevent degradation/oxidation MXene in humidity condition. Interestingly, film exhibited remarkable performance thermal cycle stability tenability. Thus, possessing unique blend outstanding shielding, light-driven heating performance, flexible water-resistant features highly promising next-generation intelligent attenuation system.

Язык: Английский

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Electrochemical synthesis of urea on MBenes

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Июль 2, 2021

Urea is an important raw material in the chemical industry and widely used as a nitrogen source fertilizers. The current industrial urea synthesis not only requires harsh reaction conditions, but also consumes most of NH3 obtained through artificial synthesis. conversion N2 CO2 into electrochemical reactions under ambient conditions represents novel green method. However, large-scale promotion this method limited by lack suitable electrocatalysts. Here, means density functional theory computations, we systematically study catalytic activity three experimentally available two-dimensional metal borides (MBenes), Mo2B2, Ti2B2, Cr2B2 toward simultaneous electrocatalytic coupling to produce conditions. According our results, these MBenes have superior intrinsic basal for formation, with limiting potentials ranging from -0.49 -0.65 eV, can significantly suppress competitive reduction NH3. In particular, 2D Mo2B2 possess capacity surface oxidation self-corrosion rendering them relatively promising electrocatalysts production. Our work paves way urea.

Язык: Английский

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Prospects challenges and stability of 2D MXenes for clean energy conversion and storage applications

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

Опубликована: Июнь 11, 2021

Abstract Two-dimensional materials have gained immense attention for technological applications owing to their characteristic properties. MXene is one of the fast-growing family 2D that exhibits remarkable physiochemical properties cater numerous in field energy and storage. This review comprises significant advancement discusses evolution design, synthetic strategies, stability. In addition illuminating state-of-the-art applications, we discuss challenges limitations preclude scientific fraternity from realizing functional with controlled structures renewable clean conversion storage applications.

Язык: Английский

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Ultrathin Cellulose Nanofiber Assisted Ambient‐Pressure‐Dried, Ultralight, Mechanically Robust, Multifunctional MXene Aerogels

Advanced Materials, Год журнала: 2022, Номер 35(1)

Опубликована: Окт. 25, 2022

Ambient-pressure-dried (APD) preparation of transition metal carbide/nitrides (MXene) aerogels is highly desirable yet remains challenging. Here, ultrathin, high-strength-to-weight-ratio, renewable cellulose nanofibers (CNFs) are efficiently utilized to assist in the APD ultralight robust, conductive, large-area MXene-based via a facile, energy-efficient, eco-friendly, and scalable freezing-exchanging-drying approach. The strong interactions large-aspect-ratio CNF MXene as well biomimetic nacre-like microstructure induce high mechanical strength stability avoid structure collapse process. Abundant functional groups CNFs facilitate chemical crosslinking aerogels, significantly improving hydrophobicity, water resistance, even oxidation stability. 1D nature renders minimal MXenes' interlayered gaps numerous heterogeneous interfaces, yielding excellent conductivity electromagnetic interference (EMI) shielding performance aerogels. synergies MXene, CNF, abundant pores improve EMI performance, photothermal conversion, absorption viscous crude oil. This work shows great promises APD, multifunctional protection or compatibility, thermal therapy, oil-water separation applications.

Язык: Английский

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Ti₃C₂T_x MXene Conductive Layers Supported Bio‐Derived Fe_x−1Se_x/MXene/Carbonaceous Nanoribbons for High‐Performance Half/Full Sodium‐Ion and Potassium‐Ion Batteries

Advanced Materials, Год журнала: 2021, Номер 33(34)

Опубликована: Июль 19, 2021

Abstract Owing to their cost‐effectiveness and high energy density, sodium‐ion batteries (SIBs) potassium‐ion (PIBs) are becoming the leading candidates for next‐generation energy‐storage devices replacing lithium‐ion batteries. In this work, a novel Fe x −1 Se heterostructure is prepared on fungus‐derived carbon matrix encapsulated by 2D Ti 3 C 2 T MXene highly conductive layers, which exhibits specific sodium ion (Na + ) potassium (K storage capacities of 610.9 449.3 mAh g at current density 0.1 A , respectively, excellent capacity retention charge–discharge rates. acts as layers prevent restacking aggregation sheets carbonaceous nanoribbons, while natural fungus functions nitrogen/carbon source provide bionic nanofiber network structural skeleton, providing additional accessible pathways high‐rate transport satisfying surface‐driven contribution ratios sweep rates both Na/K ions storages. addition, in situ synchrotron diffraction ex X‐ray photoelectron spectroscopy measurements performed reveal mechanisms de‐/alloying conversion process Na /MXene/carbonaceous nanoribbon heterostructure. As result, assembled full cells containing MXene‐supported @carbonaceous anodes possess stable large‐ion capabilities.

Язык: Английский

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Recent advances in and perspectives on pseudocapacitive materials for Supercapacitors–A review

Journal of Power Sources, Год журнала: 2022, Номер 557, С. 232558 - 232558

Опубликована: Дек. 29, 2022

Язык: Английский

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Advances and challenges in 2D MXenes: From structures to energy storage and conversions

Nano Today, Год журнала: 2021, Номер 40, С. 101273 - 101273

Опубликована: Авг. 26, 2021

Язык: Английский

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