SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Markos Medhin Ashebo,Ningning Liu,Fei Yu,Jie Ma
MXene, show a promising electrode material for capacitive deionization (CDI) due to their elevated conductivity and hydrophilic surface characteristics. Despite optimal electrochemical reaction conditions, MXene still exhibits unsatisfactory capacity. Enhancing capacitance in Nb 2 CT x MXene poses a key challenge, and addressing this involves leveraging pseudocapacitance through increased active site concentration. This study reports a method to notably improve the capacitance by incorporating cation intercalation and surface modification. After alkali treatment and thermal annealing, the obtained 400-KOH-Nb 2 C as a cathode in capacitive deionization, exhibiting notable salt adsorption capacity of 104.2 mg g −1 at 1.6 V and an efficient removal rate of 1.73 mg g −1 min −1 , cyclic stability maintained over 200 cycles. This optimized electrochemical and desalination performance is due to the large interlayer spaces of Nb 2 CT x and the surface with lowest termination of -F and –OH group, promoting the delicate surface of Nb 2 CT x MXene and accelerating ion transport. Furthermore, the derivation of KNbO 3 nanowires on 400-KOH-Nb 2 C surface further expands the layer spacing of MXene and enhances the active sites, and also acts as a protective layer to improve the stability of Nb 2 C, this effectively addressing challenges associated with desalination. This study offers a novel solution for improving Nb 2 CT x MXene electrochemical properties in CDI.
研究领域:
材料科学
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环境工程
·
电化学
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高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Jingran Huang,Junnan Tao,Guiwu Liu,Lei Lu,Hua Tang,Guanjun Qiao
Constructing heterojunction photocatalyst with a suitable band energy structure and well-defined interfacial contact is considered to be an effective way for solar-to-hydrogen conversion. CdS with suitable band structure is expected to be an excellent candidate in photocatalytic water splitting to produce hydrogen, but fast recombination of photo-generated carries usually hinders its applications. Nb 2 CT X , with lower Fermi energy level than Ti 3 C 2 T X , has been used as co-catalyst for photocatalysis due to its excellent electroconductivity and hydrophilicity. In this work, a one-step solvothermal method is used to grow in-situ one-dimensional (1D) CdS nanorods on two-dimensional (2D) Nb 2 CT X under the action of electrostatically driven self-assembly, ensuring the intimate contact at the CdS/Nb 2 CT X interface to form the 1D/2D Schottky heterojunction. Correspondingly, the CdS/Nb 2 CT X composite helps to accelerate the separation of electron-hole and charge transfer of CdS, and thus improving its photocatalytic performance. The optimized CdS/Nb 2 CT X composite (CdS/Nb 2 CT X -60) presents enhanced photocatalytic activity with hydrogen production rate of 5.3 mmol·g −1 ·h −1 under visible light, which is 1.7 times higher than that of pristine CdS.
研究领域:
材料科学
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能源化学
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光催化
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DOI
高影响因子
Journal of Food Measurement and Characterization
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2024
·
IF 2.9
Liao Diyan,Zhao Yong,Zhou Yi,Yi Yinhui,Weng Wenchuan,Zhu Gangbing
The extensive usage of organophosphate pesticides (OPs) has posed severe harm to human health and environmental system, but achieving highly effective and on-site detection is still a great challenge. In this work, a novel nanozyme Nb 2 CT x MXene/bimetallic PdPt (Nb 2 CT x @PdPt) was synthesized firstly through a simple self-reduction method, and the results show that the as-prepared Nb 2 CT x @PdPt nanozyme exhibits outstanding peroxidase-like activity. Interestingly, the nanozyme activity of Nb 2 CT x @PdPt is restrained remarkably in the presence of acetylcholine chloride and acetylcholinesterase while it can be restored through the addition of OPs (selecting glyphosate as a model). Based on this phenomenon, a sensitive colorimetric assay coupled with hydrogel and smartphone for OPs was then constructed. After optimizing various conditions, the designed sensing platform can achieve stable, rapid, and sensitive on-site detection for OPs, showing superior sensing performances: a wide linearity of 1.0 ng mL −1 –1.0 µg mL −1 and low detection limit of 0.419 ng mL −1 .
研究领域:
环境科学
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生物医学工程
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分析化学
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DOI
高影响因子
Journal of Magnesium and Alloys
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2023
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IF 17.6
Xiang Zhou,Haotian Guan,Heng Lu,Yangfan Lu,Jianbo Li,Jingfeng Wang,Yu'an Chen,Qian Li,Fusheng Pan
While early transition metal-based materials, such as MXene, has emerged as an efficient catalyst for the Mg-based hydrogen storage materials, their strong interaction with hydrogen resulted in the high hydrogen diffusion barrier, hindering further improvement of catalytic activity. A MXene is characterized by rich anionic groups on its surface, significantly affecting electronic and catalytic functionalities. Using Nb 2 C T x as an example, we herein illustrate the critical role of anionic T x defects on controlling hydrogen dissociation and diffusion processes in Mg-based hydrogen storage materials. The hydrogen desorption properties of MgH 2 can be significantly enhanced by utilizing T x controllable Nb 2 C T x , and it can release 3.57 wt.% hydrogen within 10 min under 240 °C with the reduced dehydrogenation activation barrier. It also realized stable de/hydrogenation reactions for at least 50 cycles. DFT studies combined with kinetic analysis revealed that the catalyst‒hydrogen interaction could be systematically controlled by optimizing surface T x defect density, accelerating the hydrogen dissociation and diffusion processes at the same time. These results demonstrate that the T x defects serve as the effective catalytically active centers of Nb 2 C T x , offering a flexible catalyst design guideline.
研究领域:
材料科学
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能源化学
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纳米技术
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表面科学
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催化化学
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DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
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2025
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IF 8.9
Yuwei Liu,Jiayi Tang,Jiuao Wang,Hao Yue,Zongliang Du,Xu Cheng,Haibo Wang,Xiaosheng Du
The development of form-stable phase change materials (PCMs) that combine solar-thermal storage capacity, electromagnetic interference (EMI) shielding performance, and flame-retardancy is crucial for effective building energy management and conservation. Herein, innovative Nb 2 CT x MXene/starch hybrid aerogels supported phase change composites (MSPCMs) with superior solar-thermal conversion efficiency, EMI shielding and flame-retardancy were fabricated by selectively etching of Nb 2 AlC MAX, modifying starch with sodium phytate, constructing MXene/starch hybrid aerogels (MSPAs), and impregnating aerogels with molten n -eicosane. Differential scanning calorimetry (DSC) analyses revealed that MSPCMs exhibited high PCM loading yield (up to 498.9 %) and heat storage density (up to 232.1 J/g). Nb 2 CT x MXene nanosheets significantly enhanced the solar-thermal storage efficiency (up to 87.9 %) and EMI shielding performance of MSPCMs. Additionally, increasing the content of sodium phytate in MSPAs noticeably reduced the peak heat release rate (pHRR) and the total heat release (THR) of MSPCMs, thereby improving the flame-retardant properties of the synthesized PCM composites.
研究领域:
材料科学
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能源工程
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环境科学
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DOI
高影响因子
RARE METALS
·
2022
·Vol. 42
·期 4
·1175-1185
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IF 6.318
Xiong Qian-Qian,Muhmood Tahir,Zhao Cheng-Xiao,Xu Jing-San,Yang Xiao-Fei
Transition metal-containing MXene has shown great potential in the promising research fields, and its performance strongly depends on the composition, structure, dimension, and surface chemistry. Thus, rational design and controllable synthesis of ultrathin two-dimensional (2D) MXene nanosheets with uniform surface terminations are of great importance. However, the use of 2D MXene, particularly in solar-powered photocatalysis and electrocatalysis, is restricted by the formation of thick, multi-layered MXene flakes with a small interlayer spacing produced from the conventional hydrofluoric acid (HF) etching method. In this work, we report a few-layer MXene nanosheets by solely employing a mixture of lithium fluoride and hydrochloric acid as the etching reagent. Synergic etching and intercalation technique endows MXene with ultrathin 2D nanostructures; moreover, the use of fluoride salt, rather than harmful HF, offers a safer and environmentally-friendly synthetic route for scalable green production of 2D MXene. Both the obtained Ti 3 C 2 T x and Nb 2 CT x nanosheets show a highly efficient photoelectrochemical performance superior to highly stacked MXene flakes. This work highlights a mild, simultaneous etching and delamination strategy for the development of high quality of 2D MXene nanosheets. Graphical abstract
研究领域:
材料科学
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化学工程
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环境科学
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DOI
高影响因子
Materials
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2021
·Vol. 14
·期 9
·2426
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IF 3.623
Xiaoyuan Fan,Peng Du,Xiaoxuan Ma,Ruyue Wang,Jingteng Ma,Yonggang Wang,Dongyu Fan,Yuanzheng Long,Bohan Deng,Kai Huang,Hui Wu
Production of hydrogen from water splitting has been considered as a promising solution for energy conversion and storage. Since a noble metal-based structure is still the most satisfactory but scarce kind of catalyst, it is significant to allow for practical application of such catalysts by engineering the heterogeneous structure and developing green and facile synthetic strategies. Herein, we report a mechanochemical ball milling synthesis of platinum nanoclusters immobilized on a 2D transition metal carbide MXene (Nb2CTx) as an enhanced catalyst for hydrogen evolution. After annealing at 600 °C, ultrafine Pt3Nb nanoclusters are formed on the Pt/Nb2CTxcatalyst. As prepared, the Pt/Nb2CTx-600 catalyst demonstrates superior electrochemical HER activity and stability with an ultralow overpotential of 5 mV and 46 mV to achieve 10 mA cm−2and 100 mA cm−2, respectively, in comparison with other Nb2CTx-based catalysts and commercial Pt/C catalysts. Moreover, the remarkable durability is also confirmed by accelerated durability tests (ADTs) and long-term chronoamperometry (CA) tests. The excellent HER performance was attributed to high Pt dispersion and more active site exposure by the mechanochemical process and thermal treatment. Such results suggest that the mechanochemical strategy provides a novel approach for rational design and cost-effective production of electrocatalysts, also providing other potential applications in a wide range of areas.Keywords:hydrogen evolution;Pt-Nb alloy;mechanochemical synthesis;thermal annealing
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DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
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IF 6.371
Jingran Huang,Mingyuan Wang,Xiangzhao Zhang,Junnan Tao,Lei Lu,Guanjun Qiao,Guiwu Liu
To produce high energy density , clean hydrogen fuel by photocatalytic water splitting has become one of the important strategies for solving the shortage of fossil fuels in the future, so it is of great significance to improve photocatalytic performance. MXene with high conductivity and layered nanostructure is an excellent charge transport layer material, which can effectively enhance the photocatalytic performance of composites. Here, a novel 2D CdS/2D Nb 2 CT X composite was successfully prepared by a combination of electrostatic self-assembly and solvothermal reaction. The addition of Nb 2 CT X greatly hinders the agglomeration of CdS nanosheets , and the optimized CdS/Nb 2 CT X -40 composite presents a high photocatalytic H 2 evolution rate of 5040 μmol/g/h, which is 4.3 times higher than that of pristine CdS nanosheets. In particular, the formation of Schottky heterojunction leads to a significant redistribution of charges on the CdS/Nb 2 CT X composite, which can accelerate the photo-generated charge separation and transfer of CdS nanosheets, allowing more photo-generated electrons to drive the water splitting reaction. Moreover, the photoelectrochemical measurements, electron spin resonance (ESR) detection and the first-principles calculations confirm the effective charge transfer and more active free radicals of the CdS/Nb 2 CTx composite.
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Chao Peng,Xi Xie,Wenkang Xu,Tao Zhou,Ping Wei,Jianbo Jia,Kun Zhang,Yonghai Cao,Hongjuan Wang,Feng Peng,Rui Yang,Xiqiang Yan,Hui Pan,Hao Yu
Steering charge kinetics is one of the most urgent unsolved issues in photocatalysis. The effective spatial separation of photogenerated electron-hole pairs is particularly important in the design and controllable preparation of nano-photocatalysts. Herein, one-dimensional Nb 2 O 5 nanorod arrays with [0 0 1] orientation were grown in-situ on two-dimensional Nb 2 CT x MXenes through a facile hydrothermal method for the first time. Ag nanoparticles were then photodeposited on the Nb 2 O 5 nanorods to form hierarchical 0D/1D/2D nanohybrids. It was experimentally demonstrated that OH is predominantly adsorbed on Nb 2 CT x as termination groups, which resulted in a low work function (2.7 eV). Thanks to the unique structure, the highly active [0 0 1] Nb 2 O 5 nanorods afford high-efficiency photogeneration of electron-hole pairs, while the low-work-function OH terminated Nb 2 CT x allows for trapping holes, and Ag nanoparticles act as electron reservoir and sites of hydrogen evolution reaction (HER). The ternary Ag/Nb 2 O 5 @Nb 2 CT x nanohybrids reached a record HER activity (682.2 and 824.2 μmol·g -1 h −1 use methanol and glycerol as sacrificial agents, respectively) among the niobium-based photocatalysts, demonstrating the potential of MXenes as a platform for the synthesis of high-performance heterojunction structures, where the tunable electronic property is a key factor.
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高影响因子
Biomedical Optics Express
·
2021
·Vol. 12
·期 11
·7051-7063
·
IF 3.732
Wenjie Li,Yinping Miao,Tuan Guo,Kialiang Zhang,Jianquan Yao
An optofluidic system based on photothermal spectroscopy is proposed, which combines molecular photothermal effect with Nb2CTx MXene-tilted fiber Bragg grating (TFBG) for the detection of organophosphorus pesticides (OPs) with temperature compensated. Under the irradiation of excitation light, the photothermal effect of OPs produces a detectable change in the refractive index of the sample, and the concentration of chlorpyrifos can be quantified using TFBG. The Nb2CTx MXene coated TFBG allow more molecules to be absorbed on the surface of TFBG, which enhances the interaction between light and matter, and improves the sensitivity of detection. The temperature compensation is performed by referring to the core mode of TFBG, thereby eliminating the influence of ambient temperature on the photothermal detection. The experimental results show that the sensitivity reaches 1.8 pm/ppm with a limit of detection (LOD) of 0.35 ppm, and the obtained temperature compensation coefficient is 4.84 ppm/°C. This photothermal biosensor has the advantages of low LOD, temperature compensation and real-time online monitoring, making it a good candidate in medicine, chemistry and environmental monitoring.
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PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Dandan Fang,Huizhu Ren,Yitian Huang,Hong Dai,Defu Huang,Yanyu Lin
Herein, an ultrasensitive electrochemiluminescence (ECL) immunosensor based on a high performance probe of Nb 2 CTx MXene immobilized ZnO quantum dots (QDs) was constructed for Thyroglobulin (Tg) detection. ZnO QDs with good biocompatibility and catalytic property was for the first time utilized as coreaction accelerator in Ru(bpy) 3 2+ /S 2 O 8 2− system and enhanced ECL signal. Specifically, ZnO QDs can facilitate S 2 O 8 2− reduction to generate more SO 4 − , and then reacted with cathodic radical of Ru(bpy) 3 2+ , realizing 2-fold enhancement in ECL intensity. Additionally, Nb 2 CTx MXene possesses excellent properties and was used as prominent supporter, improving the loading capacity of Ru(bpy) 3 2+ and ZnO QDs, and accelerating the electron transfer, resulting in ECL signal enhancement. Furthermore, Nb 2 CTx MXene acted as temperature controller and increased the electrode surface temperature by converting laser energy into heat, further amplified ECL signal. Because of the high sensitivity, good specificity and favorable stability, the proposed immunosensor realized sensitive detection of Thyroglobulin and had a great application prospect in bioanalysis and clinical diagnosis.
研究领域:
分析化学
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生物医学工程
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临床诊断
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产品关联
DOI
高影响因子
TALANTA
·
2024
·
IF 5.6
Lekai Chang,Shuli Bai,Ping Wei,Xingyue Gao,Jinfeng Dong,Bingpu Zhou,Chao Peng,Jianbo Jia,Tiangang Luan
In this study, the plasmonic Ag nanoparticles (Ag NPs) were uniformly anchored on the high conductivity Nb 2 C T x (MXene) nanosheets to construct an Ag/Nb 2 C T x substrate for surface-enhanced Raman spectroscopy (SERS) detection of polystyrene (PS) nanoplastics. The KI addition (0.15 mol/L), the volume ratio between substrate colloid and nanoplastic suspension (2:1), and the mass ratio of Nb 2 C T x in substrate (14%) on SERS performance were optimized. The EM hot spots of Ag/Nb 2 C T x are significantly enlarged and enhanced, elucidated by FDFD simulation. Then, the linear relationship between the PS nanoplastics concentration with three different sizes (50, 300, and 500 nm) and the SERS intensity was obtained (R 2 > 0.976), wherein, the detection limit was as low as 10 −4 mg/mL for PS nanoplastic. Owing to the fingerprint feature, the Ag/Nb 2 C T x -14% substrate successfully discerns the mixtures from two-component nanoplastics. Meanwhile, it exhibits excellent stability of PS nanoplastics on different detection sites. The recovery rates of PS nanoplastics with different sizes in lake water ranged from 94.74% to 107.29%, with the relative standard deviation (RSD) ranging from 2.88% to 8.30%. Based on this method, the expanded polystyrene (EPS) decomposition behavior was evaluated, and the PS concentrations in four water environments were analyzed. This work will pave the way for the accurate quantitative detection of low concentration of nanoplastics in aquatic environments.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
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