MOLECULES
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2022
·Vol. 27
·期 15
·4890
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IF 4.927
Xin Tao,Linlin Zhang,Xuedong He,Lingzi Fang,Hongyan Wang,Li Zhang,Lianghao Yu,Guang Zhu
Flexible supercapacitors (FSCs) are limited in flexible electronics applications due to their low energy density. Therefore, developing electrode materials with high energy density, high electrochemical activity, and remarkable flexibility is challenging. Herein, we designed nitrogen-doped porous MXene (N-MXene), using melamine-formaldehyde (MF) microspheres as a template and nitrogen source. We combined it with an electrospinning process to produce a highly flexible nitrogen-doped porous MXene nanofiber (N-MXene-F) as a self-supporting electrode material and assembled it into a symmetrical supercapacitor (SSC). On the one hand, the interconnected mesh structure allows the electrolyte to penetrate the porous network to fully infiltrate the material surface, shortening the ion transport channels; on the other hand, the uniform nitrogen doping enhances the pseudocapacitive performance. As a result, the as-assembled SSC exhibited excellent electrochemical performance and excellent long-term durability, achieving an energy density of 12.78 Wh kg−1at a power density of 1080 W kg−1, with long-term cycling stability up to 5000 cycles. This work demonstrates the impact of structural design and atomic doping on the electrochemical performance of MXene and opens up an exciting possibility for the fabrication of highly FSCs.Keywords:flexible supercapacitors;nitrogen-doped 3D MXene;electrospinning
研究领域:
材料科学
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能源存储
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DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Kangle Li,Peng Zhang,Razium Ali Soomro,Bin Xu
MXenes have emerged as promising electrode materials for supercapacitors based on their metallic conductivity, good hydrophilicity, rich surface chemistry, and excellent mechanical characteristics. However, the strong interlayer van der Waals forces induce significant layer restacking, which restrict complete exposure of MXenes’ surface active sites, impeding electron/ion transport and resulting in poor electrochemical performances. Herein, a porous MXene/carbon nanotube (CNT) film was prepared through a simple alkali-induced process. The developed porosity and the introduction of CNTs can effectively suppress the restacking of MXene nanosheets, promoting the effective utilization of the surface active sites of the MXene and facilitating fast ion/electron transportation. Consequently, the porous MXene/CNT film exhibited a high specific capacitance of 401.4 F g–1 at 1 A g–1 and a sustained capacitance of 336.2 F g–1 at an ultrahigh current density of 1000 A g–1, corresponding to an 83.8% capacitance retention. Furthermore, the film electrode demonstrated outstanding cycling stability, with a capacitance retention of 99.0% after 20,000 cycles at 100 A g–1, showing its significant potential for supercapacitor applications.
研究领域:
材料科学
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电化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2021
·
IF 4.527
Shilong Li,Wei Gu,Yuqing Sun,Dong Zou,Wenheng Jing
MXene (Ti 3 C 2 T x ) is a novel, two-dimensional (2D) layered material that is atomically thin, exhibits good mechanical strength , and is ideal for fabricating efficient membranes for molecular separation. However, the applications of MXene membranes are limited by their low water permeability owing to narrow channels and high tortuosity. A novel strategy for introducing artificial pores on the surface of MXene nanosheets via gentle in situ chemical etching with hydrogen peroxide (H 2 O 2 ) to prepare porous MXene nanosheets (PMS) is reported herein. This greatly increases the water permeability of MXene membranes while retaining the high rejection of small-molecule dyes. Permeable pores generated on MXene nanosheets transform the transport model of water molecules in the membrane from typical horizontal transport pathways dominated by interlayer channels to longitudinal–lateral three-dimensional transport pathways, affording increased water molecule transport channels and reduced transport distance. Based on different etching conditions, the obtained membranes exhibit high pure-water permeability ranging from 9.37 to 42.48 L m −2 h −1 bar −1 . Moreover, mild etching maintains the 2D structure of the membrane and retains a nearly complete rejection of congo red dye. This study provides a novel and effective strategy for preparing high-performance porous laminar MXene membranes for dye-separation applications.
研究领域:
材料科学
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化学工程
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纳米技术
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
·
IF 13.3
Lili Zhu,Hao Zhang,Zuming Hu,Junrong Yu,Yan Wang
To acquire excellent wave-absorbing materials with broadened applications, transition metal carbides (Ti 3 C 2 T x , MXene) have been the research focus. However, the high conductivity of MXene limits its electromagnetic wave (EMW) absorption capability; meanwhile, the inferior mechanical properties of MXene-based aerogels severely restrict their applications. Here, porous MXene (PMXene) nanosheets were prepared by hydrogen peroxide etching, which was then physically and chemically crosslinked with cellulose nanofibres (CNF) to successfully prepare PMXene/CNF composite wave-absorbing aerogels with excellent mechanical properties. PMXene/CNF aerogel achieved a minimum reflection loss (RL min ) of − 72.27 dB and an effective absorption bandwidth (EAB) of 5 GHz at a thickness of 1.63 mm without any magnetic component. The aerogels exhibited excellent environmental stability at a density of 12.5 mg/cm 3 , including fatigue resistance (100 compression cycles, 0.075 energy loss efficiency) and low-temperature resistance. Refining the mechanical properties exploits the aerogel’s potential for motion monitoring and electronic skin applications. In addition, the aerogels integrate properties such as water–oil separation, photothermal conversion, and thermal insulation (thermal conductivity of 0.045 W/(m-K)). Therefore, multifunctional PMXene/CNF aerogels have a broad potential for future application in the defence industry, electronic devices, and smart wearable fields.
研究领域:
材料科学
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电磁学
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环境科学
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机械工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
·
IF 8.6
Yufei Wang,Zong Lu,Mide Luo,Ziqi Zhao,Yanying Wei,Haihui Wang
The recovery of uranium from nuclear wastewater holds considerable importance in safeguarding water resources and addressing the issue of nuclear energy scarcity. Recently, modified MXenes have emerged as a promising adsorbent for U(VI)-containing wastewater due to their abundant active sites and exceptional radiation resistance, but the incorporation of costly functional molecules is usually necessary to yield satisfactory performance. In this work, we synthesized a novel kind of nano-porous Ti 3 C 2 T x MXene nanosheets using a simple pore-creating method with Cu 2+ as catalysts, which were tested for U(VI) elimination. Impressively, the U(VI) adsorption capacity (299 mg/g) of the porous MXene nanosheets surpassed that of most previously reported modified MXene and other materials. Meanwhile, Pseudo-second-order kinetics and Freundlich models provided suitable descriptions of the adsorption process, indicating heterogeneous chemisorption occurred. Experimental and spectral analysis suggested that the enhanced U(VI) adsorption capacity of the porous MXene nanosheets primarily benefited from more active OH groups on their surface to form bidentate coordination with U(VI). This work provided a valuable concept for preparing new MXene-based adsorbent for uranium removal.
研究领域:
材料科学
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环境科学
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核能工程
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Guozhen Guan,Peixuan Li,Xin Shi,Lei Lu,Yuchao Fan,Jie Xu,Yuanyuan Shang,Yingjiu Zhang,Jinquan Wei,Fengmei Guo
MXenes, a family of the typical two-dimensional materials, that are considered to be an excellent candidate material for supercapacitors , due to their large surface area, high conductivity and high specific pseudocapacitance. However, when assembled into electrode, MXene nanosheets are easy to aggregate because of the strong Van der Waals force. The assembled dense structure will limit the transport of electrolyte, decrease the active sites and electrochemical performance. In this work, in order to suppress the self-restacking of nanosheets and introduce more electrolyte transport channels, Ti 3 C 2 T x nanosheets are partially oxidized and etched to get porous nanosheets. Film electrode based on porous Ti 3 C 2 T x nanosheets shows higher specific surface area (48.3 m 2 /g) and improved electrochemical performance, including a high specific capacitance of 385 F/g at 1 A/g and good cycle stability of 92 % after 10,000 CV cycles at 100 mV/s.
研究领域:
材料科学
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电化学
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纳米技术
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2024
·Vol. 25
·期 23
·13226
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IF 4.9
Sha Wang,Zhe Sun,Mehraj Ahmad,Mengyu Miao
Two-dimensional (2D) nanofluidic channels are emerging as potential candidates for harnessing osmotic energy from salinity gradients. However, conventional 2D nanofluidic membranes suffer from high transport resistance and low ion selectivity, leading to inefficient transport dynamics and limiting energy conversion performance. In this study, we present a novel composite membrane consisting of porous MXene (PMXene) nanosheets featuring etched nanopores, in conjunction with cellulose nanofibers (CNF), yielding enhancement in ion flux and ion selectivity. A mild H2O2oxidant is employed to etch and perforate the MXene sheets to create a robust network of cation transportation nanochannels that effectively reduces the energy barrier for cation transport. Additionally, CNF with a unique nanosize and high charge density further enhances the charge density and mechanical stability of the nanofluidic system. Under neutral pH and room temperature, the PMXene/CNF membrane demonstrates a maximum output power density of 0.95 W·m−2at a 50-fold KCl gradient. Notably, this represents a 43% improvement over the performance of the pristine MXene/CNF membrane. Moreover, 36 nanofluidic devices connected in series are demonstrated to achieve a stable voltage output of 5.27 V and power a calculator successfully. This work holds great promise for achieving sustainable energy harvesting with efficient osmotic energy conversion utilization.
研究领域:
材料科学
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能源技术
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环境科学
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DOI
PubMed
高影响因子
ACS Applied Nano Materials
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2024
·
IF 5.3
Lu Tang,Huajing Wang,Zhenming Du,Chaoqi Zhu,Chaofan Ma,Dawen Zeng
Due to the large band gap, most metal oxide semiconductor (MOS)-based gas sensors operate at high temperatures, which greatly limits their performance for gas sensing. In this work, we reported the successful synthesis of nanocomposites consisting of porous MXene nanosheets formed by the sublimation of sulfur and SnO2 nanoparticles (S-PM/SnO2). To prevent the restacking of MXene flakes under van der Waals force, a sacrificial S-template method was employed to transform MXene into a three-dimensional (3D) structure. The presence of MXene lowers the operating temperature. With a high response (∼30.6 – 10 ppm of H2S), rapid response speed (∼16.6 s – 50 ppm of H2S), high sensitivity (∼3.12 ppm–1), low detection limits (distinct response to 100 ppb H2S), and good selectivity at 100 °C, the sensor based on the optimal sample of S-PM/SnO2-6 demonstrates excellent H2S sensing performance. The improvement in H2S gas-sensing capacity can be attributed to the development of heterojunctions at the interface of porous MXene nanosheets (S-PM) and SnO2 nanoparticles (NPs). This leads to an enlarged surface depletion region and an elevated potential barrier, which significantly amplifies the range of resistance variation. These results suggest that S-PM/SnO2 nanocomposite has promising prospects in the realm of low-temperature and highly sensitive H2S detection.
研究领域:
材料科学
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传感器技术
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DOI
高影响因子
Nanoscale
·
2018
·Vol. 10
·期 20
·9642-9652
·
IF 7.233
Zhimin Fan,Youshan Wang,Zhimin Xie,Xueqing Xu,Yin Yuan,Zhongjun Cheng,Yuyan Liu
MXene films are attractive for use in advanced supercapacitor electrodes on account of their ultrahigh density and pseudocapacitive charge storage mechanism in sulfuric acid. However, the self-restacking of MXene nanosheets severely affects their rate capability and mass loading. Herein, a free-standing and flexible modified nanoporous MXene film is fabricated by incorporating Fe(OH)3 nanoparticles with diameters of 3–5 nm into MXene films and then dissolving the Fe(OH)3 nanoparticles, followed by low calcination at 200 °C, resulting in highly interconnected nanopore channels that promote efficient ion transport without compromising ultrahigh density. As a result, the modified nanoporous MXene film presents an attractive volumetric capacitance (1142 F cm−3 at 0.5 A g−1) and good rate capability (828 F cm−3 at 20 A g−1). Furthermore, it still displays a high volumetric capacitance of 749 F cm−3 and good flexibility even at a high mass loading of 11.2 mg cm−2. Therefore, this flexible and free-standing nanoporous MXene film is a promising electrode material for flexible, portable and compact storage devices. This study provides an efficient material design for flexible energy storage devices possessing high volumetric capacitance and good rate capability even at a high mass loading.
研究领域:
材料科学
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能源存储技术
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DOI
PubMed
高影响因子
Research
·
2022
·
IF 11.036
Yongfa Cheng,Li Li,Zunyu Liu,Shuwen Yan,Feng Cheng,Yang Yue,Shuangfeng Jia,Jianbo Wang,Yihua Gao,Luying Li
The development of smart wearable electronic devices puts forward higher requirements for future flexible electronics. The design of highly sensitive and high-performance flexible pressure sensors plays an important role in promoting the development of flexible electronic devices. Recently, MXenes with excellent properties have shown great potential in the field of flexible electronics. However, the easy-stacking inclination of nanomaterials limits the development of their excellent properties and the performance improvement of related pressure sensors. Traditional methods for constructing 3D porous structures have the disadvantages of complexity, long period, and difficulty of scalability. Here, the gas foaming strategy is adopted to rapidly construct 3D porous MXene aerogels. Combining the excellent surface properties of MXenes with the porous structure of aerogel, the prepared MXene aerogels are successfully used in high-performance multifunctional flexible pressure sensors with high sensitivity (306 kPa -1), wide detection range (2.3 Pa to 87.3 kPa), fast response time (35 ms), and ultrastability (>20,000 cycles), as well as self-healing, waterproof, cold-resistant, and heat-resistant capabilities. MXene aerogel pressure sensors show great potential in harsh environment detection, behavior monitoring, equipment recovery, pressure array identification, remote monitoring, and human-computer interaction applications.
研究领域:
材料科学
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电子工程
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传感器技术
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
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IF 9.7
Jinfeng Liu,Chengcheng Wang,Liping Zhang,Shaohai Fu
As a critical component for real-time monitoring in smart wearable devices, dual-mode strain sensors offer instantaneous responses to mechanical stimuli through optical and electrical signals, playing a crucial role in monitoring human physiological states in real time. Here, an innovative dual-mode strain sensing fiber was designed and fabricated by integrating PS@P(MMA-BA) photonic crystal nanospheres onto MXene/TPU electrical sensing fibers. It swiftly responds to strain stimuli while simultaneously delivering optical and electrical signals. Based on the advantages of preparation methodology and sensing sensitivity, the smart fiber sensor exhibits rapid fabrication, angle-independent structural color, dynamic visual color change, a wide strain range (0–50 %), and high sensitivity (GF: 22.55 at 10 %). The design concept of dual-mode strain sensing fiber holds promising applications in wearable technology for real-time monitoring of human–machine interaction, health tracking, and smart wearable devices.
研究领域:
材料科学
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生物医学工程
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智能可穿戴设备
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Chenxue Yao,Wenqian Zhang,Lijian Xu,Mengmeng Cheng,Yan Su,Jie Xue,Jinglei Liu,Shifeng Hou
In this work, we report a facile and scalable approach to synthesis a porous MXene/single-walled carbon nanotubes (p-MXene/SWCNTs) film as a freestanding electrode for the electrosorption of the organic dyes in wastewater. Dye adsorption of wastewaters is a crucial issue in the water treatment. Nevertheless, there are still several obstacles in the adsorption process hindering its practical application, such as the low efficiency and hard recycle. Electrosorption is an electrochemically accelerate adsorption technique with high removal efficiency, low cost and easy control. As a result, the as-prepared p-MXene/SWCNTs film shows spectacular adsorption capacity for methylene blue (MB) with 1068.8 mg g −1 when the applied voltage is −1.2 V, which is much higher than that of open circuit with 55.8 mg g −1 . Notably, the as-prepared electrode exhibits excellent reusability without secondary pollution and the maximum adsorption capacity is up to 28403.7 mg g −1 . In addition, it also possesses outstanding selective adsorption for MB and methyl orange (MO) by adjusting the pH values. We anticipate that this strategy of designing p-MXene/SWCNTs film as a freestanding electrode material will be a promising way to remove organic dyes in the wastewaters. Furthermore, we forecast that the as-synthesized p-MXene/SWCNTs film is promising to be acted as flexible electrode applicating in capacitive deionization, supercapacitors, solar cell, catalysts, and biosensors.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
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