A hierarchically porous and hydrophilic 3D nickel–iron/MXene electrode for accelerating oxygen and hydrogen evolution at high current densities

Nano Energy, Journal Year: 2019, Volume and Issue: 63, P. 103880 - 103880

Published: July 6, 2019

Language: Английский

---

2D Early Transition Metal Carbides (MXenes) for Catalysis

Small, Journal Year: 2019, Volume and Issue: 15(29)

Published: Jan. 22, 2019

Abstract MXenes, a bourgeoning class of 2D transition metal carbides, are considerable interest in catalysis due to their rich surface chemistry, tunable electronic structures, and thermal stability. Here, recent conceptual advances applying MXenes nanocomposites (photo)electrocatalysis conventional heterogeneous highlighted. In addition, the nature active sites MXene‐based catalysts discussed significance challenges future development using as platforms summarized.

Language: Английский

---

Cr‐Doped FeNi–P Nanoparticles Encapsulated into N‐Doped Carbon Nanotube as a Robust Bifunctional Catalyst for Efficient Overall Water Splitting

Advanced Materials, Journal Year: 2019, Volume and Issue: 31(15)

Published: Feb. 21, 2019

Exploring high-efficiency, stable, and cost-effective bifunctional electrocatalysts for overall water splitting is greatly desirable challenging. Herein, a newly designed hybrid catalyst with Cr-doped FeNi-P nanoparticles encapsulated into N-doped carbon nanotubes (Cr-doped FeNi-P/NCN) unprecedented electrocatalytic activity developed by simple one-step heating treatment. The as-synthesized FeNi-P/NCN moderate Cr doping exhibits admirable oxygen evolution reaction hydrogen activities overpotentials of 240 190 mV to reach current density 10 mA cm-2 in 1 m KOH solution. When used as catalyst, it needs only 1.50 V give , which superior its typically integrated Pt/C RuO2 counterparts (1.54 @ ). Density functional theory calculation confirms that FeNi-host can effectively alter the relative Gibbs adsorption energy reduces theoretical overpotential. Additionally, synergetic effects between NCNs are regarded significant contributors accelerate charge transfer promote catalysts.

Language: Английский

---

Engineering 3D Ion Transport Channels for Flexible MXene Films with Superior Capacitive Performance

Advanced Functional Materials, Journal Year: 2019, Volume and Issue: 29(14)

Published: Feb. 12, 2019

Abstract 2D MXene materials are of considerable interest for future energy storage. A film could be used as an effective flexible supercapacitor electrode due to its flexibility and, more importantly, high specific capacitance. However, although it has excellent electronic conductivity, sluggish ionic kinetics within the becomes a fundamental limitation electrochemical performance. To compensate relative deficiency, films frequently reduced several micrometer dimensions with low mass loading (<1 mg cm −2 ), point detriment areal performance and commercial value. Herein, first time, design 3D porous MXene/bacterial cellulose (BC) self‐supporting is reported ultrahigh capacitance (416 F g −1 , 2084 mF ) outstanding mechanical properties flexibility, even when reaches 5 . The highly interconnected MXene/BC network enables both electron ion transport channel. Additionally, maximum density 252 µWh achieved in asymmetric supercapacitor, higher than that all ever‐reported MXene‐based supercapacitors. This work exploits simple route assembling into state‐of‐the‐art electrodes storage devices.

Language: Английский

---

The Assembly of MXenes from 2D to 3D

Advanced Science, Journal Year: 2020, Volume and Issue: 7(7)

Published: Feb. 13, 2020

Since their discovery in 2011, transition metal carbides or nitrides (MXenes) have attracted a wide range of attention due to unique properties and promise for use variety applications. However, the low accessible surface area poor processability MXene nanosheets caused by restacking severely hindered practical use, this is expected be solved integrating them into macroscopic assemblies. Here, recent progress construction assemblies from 2D 3D at macro and/or microlevel summarized. The mechanisms assembly are also discussed better understand relationship between performance assembled structure. possible uses energy conversion storage, electromagnetic interference shielding absorption, other applications

Language: Английский

---

In Situ Ice Template Approach to Fabricate 3D Flexible MXene Film‐Based Electrode for High Performance Supercapacitors

Advanced Functional Materials, Journal Year: 2020, Volume and Issue: 30(47)

Published: April 22, 2020

Abstract MXenes with metallic conductivity, high pseudo‐capacitance and 2D structure, are promising flexible electrode materials for supercapacitors, but suffer from the restacking issue, which hinders ion accessibility causes sluggish kinetics. Herein, a simple in situ ice template strategy is proposed to fabricate free‐standing, 3D porous Ti 3 C 2 T x /carbon nanotubes (CNTs) film (3D‐PMCF) by freeze‐drying ‐based hydro‐films without any postprocessing. During process, small grains transformed residual water molecules interlayer then act as self‐sacrifice construct network. CNTs introduced hydro‐film increase amount of resultant porosity. The structure significantly increases exposed surface active sites accelerates transport, meanwhile maintaining good flexibility. Consequently, 3D‐PMCF delivers capacitance 375 F g −1 at 5 mV s retains 251.2 1000 excellent cycling stability, much superior conventional densely stacked film. Being assembled into symmetric supercapacitor, an energy density 9.2 Wh kg realized. This work demonstrates efficient route constructing high‐performance MXene electrodes supercapacitors.

Language: Английский

---

Porous MXenes: Synthesis, structures, and applications

Nano Today, Journal Year: 2019, Volume and Issue: 30, P. 100803 - 100803

Published: Nov. 17, 2019

Language: Английский

---

Flexible resistive NO2 gas sensor of three-dimensional crumpled MXene Ti3C2Tx/ZnO spheres for room temperature application

Sensors and Actuators B Chemical, Journal Year: 2020, Volume and Issue: 326, P. 128828 - 128828

Published: Sept. 1, 2020

Language: Английский

---

Recent Advances in Functional 2D MXene‐Based Nanostructures for Next‐Generation Devices

Advanced Functional Materials, Journal Year: 2020, Volume and Issue: 30(49)

Published: Sept. 9, 2020

Abstract Similar to graphene and black phosphorus (BP), 2D transition metal carbides nitrides (MXenes) are of great interest in a variety fields, such as energy storage conversion, sensors, electromagnetic interference (EMI) shielding, photothermal therapy due their excellent conductivity hydrophilicity, large specific capacitance, high effect, superior electrochemical performance. To further broaden applicable ranges beyond existing boundaries fully exploit these potentials, functional MXene nanostructures recent years have been rationally designed developed by various approaches, doping strategies, surface functionalization, hybridization, for next‐generation devices with the merits low power consumption, intelligence, high‐integration chips. This review provides an overview synthetic routes fundamental properties nanostructures, including surface‐modified MXenes mixed‐dimensional MXene‐based heterostructures, highlights state‐of‐the‐art progress applications regard catalysis, photodetectors, EMI degradation, biomedical applications, presents challenges perspectives burgeoning fields. It is hoped that this will inspire more efforts toward research on new satisfy growing requirements systems.

Language: Английский

---

One‐dimensional and two‐dimensional synergized nanostructures for high‐performing energy storage and conversion

InfoMat, Journal Year: 2019, Volume and Issue: 2(1), P. 3 - 32

Published: Nov. 12, 2019

Abstract To address the worldwide energy challenges, advanced storage and conversion systems with high comprehensive performances, as promising technologies, are inevitably required on a timely basis. The performance of these is intimately dependent properties their electrodes. In addition to electrode materials selection compositional optimization, fabrication designed nanostructure also provides significant benefits for performances. past decade, considerable efforts have been made promote search multidimensional nanostructures containing both one‐dimensional (1D) two‐dimensional (2D) in synergy, namely, 1D‐2D synergized nanostructures. By developing freestanding electrodes such unique nanoarchitectures, structural features electroactivities each component can be manifested, where synergistic among them simultaneously obtained further enhanced properties, increased number active sites, fast electronic/ionic transport, so forth. This review overviews state‐of‐the‐art nanostructures, which broadly divided into three groups, core/shell, cactus‐like, sandwich‐like For category, we introduce from aspects features, methodologies successful applications different types storage/conversion devices, including rechargeable batteries, supercapacitors, water splitting, Finally, main challenges faced by perspectives discussed. image

Language: Английский

---