CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Haohang Song,Yusheng Ma,Qian Yao,Chao Liu,Xuesong Li,Xutang Tao
MXene has attracted broad attention for its unique physicochemical properties and has flourished in many research areas. Since MXene obtained by high crystalline-quality MAX phase has excellent stability and properties, the etching of high crystalline-quality MAX phase and delamination into monolayer will become an inevitable trend. However, the delamination of the high crystalline-quality MXene is significantly more challenging than conventional MXene because of the more vital van der Waals forces of the more regular interlayer structure. Here, we propose a freeze-sonication delamination (FSD) strategy that can solve the difficult problem of efficiently exfoliation of high crystalline-quality MXene. The principle is to utilize the synergistic effect of ultrasound and ionic intercalation to allow a large number of water molecules to penetrate into the interlayer, which results in volume expansion, and then ultrasound to obtain monolayer MXene in a frozen state. This method not only increases the yield of high crystalline-quality monolayer MXene but also prevents the size reduction and the nanosheet destruction. The yield of monolayer MXene reached 74.2 % with a concentration of 19.8 mg/mL after six FSD cycles (the time of ultrasound treatment is 5 min after per freeze). Meanwhile, under the protection of ice, the obtained monolayer MXene has a larger size with more complete nanosheets than ultrasound-delaminated MXene. Supercapacitors made of high crystalline-quality MXene exhibits excellent gravimetric capacitance of 261.1 F/g and satisfactory cycling stability.
研究领域:
材料科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
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2024
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IF 14
Yangyang Chen,Yu Liao,Ying Wu,Lei Li,Zhen Zhang,Sha Luo,Yiqiang Wu,Yan Qing
Lithium-sulfur batteries (LSBs) are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness. However, the low conductivity and polysulfide shuttling effect of S cathodes severely hamper the practical performance of LSBs . Herein, in situ-generated single layer MXene nanosheet/hierarchical porous carbonized wood fiber (MX/PCWF) composites are prepared via a nonhazardous eutectic activation strategy coupled with pyrolysis-induced gas diffusion. The unique architecture, wherein single layer MXene nanosheets are constructed on carbonized wood fiber walls, ensures rapid polysulfide conversion and continuous electron transfer for redox reactions. The C–Ti–C bonds formed between MXene and PCWF can considerably expedite the conversion of polysulfides, effectively suppressing the shuttle effect. An impressive capacity of 1301.1 mA h g −1 at 0.5 C accompanied by remarkable stability is attained with the MX/PCWF host, as evidenced by the capacity maintenance of 722.6 mA h g −1 after 500 cycles. Notably, the MX/PCWF/S cathode can still deliver a high capacity of 886.8 mA h g −1 at a high S loading of 5.6 mg cm −2 . The construction of two-dimensional MXenes on natural wood fiber walls offers a competitive edge over S-based cathode materials and demonstrates a novel strategy for developing high-performance batteries.
研究领域:
材料科学
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能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
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2022
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IF 8.943
Hongwei Wang,Fang Wu,Zhiheng Wang,Yang Wang,Shufang Zhang,Haijun Luo,Zhiqin Zheng,Liang Fang
Chromium (VI) removal is crucial to the safety of water resources, but there is still a lack of effective and fast dislodge methods, especially the on-site rapid remediation and emergency removal technology . Herein, the monolayer (ML) Ti 3 C 2 T x nanosheets (NSs) were prepared to remove Cr (VI) from water. The solution sample of the two-dimensional (2D) Ti 3 C 2 T x NSs demonstrate ultrafast adsorption kinetics (the concentration decreasing from 300 to 3 mg L −1 in 10 min) and impressively high capacity (1483 mg g −1 ), which is several times higher than that of the most reported Cr (VI) adsorption by Ti 3 C 2 T x . The analysis of the adsorption kinetics and isotherm models indicates that the adsorption reaction is endothermic, with physical and chemical adsorption coexisting (mainly monolayer chemical adsorption). The joint study of the experimental analysis and theoretical calculation based on the density functional theory (DFT) demonstrates that the extraordinary removal performance of Cr (VI) is due to the synergetic effect of reduction reaction removal and electrostatic adsorption. It is found that the Cr (VI) is mainly reduced by the OH- terminals on Ti 3 C 2 , and the detoxified Cr (III) is anchored on the surface of Ti 3 C 2 T x through complexation reaction with O terminal. The advantages of ultrafast adsorption kinetics and extra-high adsorption capacity of the single-layered Ti 3 C 2 T x for Cr (VI) removal make it a remarkable candidate for rapid and urgent removal of Cr (VI) wastewater.
研究领域:
环境科学
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材料科学
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化学工程
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水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
Dongli Li,Yinan Dong,Hua Zhang,Dagang Liu,Zhituo Geng,Chenxi Li,Hao Li,Jiayao Zhou,Zhipeng Li,Hai Lin,Weitian Zhang,Shengze Yu,Shuyan Yu,Congju Li,Yongping Huang,Jingkun Jiang,Zehui Li
Nitrogen oxides (NO x ) monitoring requires sensor platforms that deliver ppb-level sensitivity, ambient-temperature operation, and molecular discrimination. However, rapid and selective NO x detection at room temperature remains elusive. Although 2D transition metal carbides/nitrides (MXenes) show promise in chemiresistive sensing, their susceptibility to ambient degradation and poor selectivity limit practical deployment. Here, a room-temperature NO x sensor is developed by epitaxially growing Hofmann-type metal–organic frameworks (Ni-pyz) on oxygen-terminated monolayer large-size MXene (Ti 3 C 2 T x ). The Ni-pyz/Ti 3 C 2 T x heterostructure exhibits enhanced sensitivity (4.8 and 5.5 times compared to Ti 3 C 2 T x ) and low detection limits (8.8 and 6.9 ppb) for NO and NO 2 , along with high selectivity and good stability (>85% response after 8 weeks). The enhanced sensitivity results from electronic coupling between the Ti 3 C 2 T x and Ni(CN) 4 , promoting charge transfer with NO x . The improved selectivity arises from the pore confinement effect of Ni-pyz and the specific adsorption of NO x through Lewis acid-base interactions with open Ni sites. Importantly, the dynamic response of Ni-pyz/Ti 3 C 2 T x closely mirrors that of a trace-level chemiluminescence NO x analyzer at low NO x concentrations, enabling high-temporal-resolution, long-term atmospheric monitoring. This functional strategy overcomes the insufficiency of MXene-based gas sensors, paving the way for the development of high-performance sensors.
研究领域:
材料科学
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纳米技术
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化学传感
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环境监测
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金属有机框架（MOFs）
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）