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
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
·
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.
研究领域:
材料科学
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能源科学
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纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Shareen Shafique,Akeel Qadir,Taimoor Iqbal,Muhammad Sulaman,Liu Yang,Yanna Hou,Yuchen Miao,Jun Wu,Yuheng Wang,Fei Zheng,Xu Wang,Ziyang Hu
Defect-induced charge carrier recombination at the interface of charge transport layers and perovskite layer is a major limiting factor in the performance of perovskite photodetectors. Buried interface defect passivation presents a distinctive approach to reducing dark current and improving responsivity and detectivity in photodetectors. Herein, we propose a novel strategy for passivating buried interface defects by incorporating Nb 2 CT x at the perovskite/hole transport layer (HTL) interface to enhance optoelectronic performance of self-powered perovskite photodetectors. These strategies effectively improve charge transfer within the HTLs and suppress charge carrier recombination. Without an external bias, utilizing the Nb 2 CT x buried interface layer enables the achievement of exceptionally high responsivity and detectivity values of 0.23 A/W and 1.27×10 11 Jones, respectively, significantly outperforming the reference device. Moreover, our findings reveal an impressively broad linear dynamic range of approximately 140 dB, accompanied by rapid rise and fall times of 14.4 μs and 2.10 μs, respectively. This study illustrates a straightforward yet efficient approach for passivating buried interface defects using Nb 2 CT x in photodetectors, making Nb 2 CT x a promising material for applications in photodetectors, light-emitting diodes, photovoltaics, sensors, and more.
研究领域:
材料科学
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光电子学
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半导体物理
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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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 COLLOID AND INTERFACE SCIENCE
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2024
·
IF 9.4
Chao Peng,Yiming Chen,Xingyue Gao,Ping Wei,Yihao Lin,Li Fu,Bingpu Zhou,Mengchen Zhang,Jianbo Jia,Tiangang Luan
In this study, leveraging the tunable surface groups of MXene , the two-dimensional (2D) Nb 2 C T x with OH terminal (NC) was synthesized. 2D ZnIn 2 S 4 (ZIS) nanosheets were prepared with the aid of sodium citrate, enhancing the exposure ratio of active (1 1 0) facet. On this basis, 2D/2D ZnIn 2 S 4 /Nb 2 C T x heterojunctions were fabricated to improve photocatalytic hydrogen evolution reaction (HER) performance. The optimized 6 wt%Nb 2 C T x /ZnIn 2 S 4 -450 (6NC/ZIS-450) photocatalyt exhibits a remarkable HER rate of 3603 μmol g −1 h −1 , which is 10 times superior to that of the original ZnIn 2 S 4 . Its apparent quantum efficiency (AQE) at 380 nm reaches 14.9 %. Meanwhile, even after 5 rounds of HER, the activity of 2D/2D ZnIn 2 S 4 /Nb 2 C T x heterojunction remained at 90 %, far superior to that of pure ZnIn 2 S 4 (34 % and 31 %). Energy band structure analysis and density functional theory (DFT) calculation indicate that Nb 2 C T x adsorbed with OH exhibit a low work function . By serving as a hole cocatalyst, it effectively boosts the photocatalytic HER rate of ZnIn 2 S 4 /Nb 2 C T x heterojunction and inhibits the photocorrosion of ZnIn 2 S 4 . This unique insight, via hole transport highways and increased exposure of active facets, effectively enhances the activity and stability of sulfides photocatalysts .
研究领域:
材料科学
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能源化学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
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2024
·
IF 8.3
Xiaoxue Zhu,Kai Yang,Zhen Zhang,Siyuan He,Zihao Shen,Wei Jiang,Yiling Huang,Yan Xu,Qiutong Jiang,Limei Pan,Qian Li,Jian Yang
MXenes, represented by Ti3C2Tx, have been widely studied in the electrochemical energy storage fields, including lithium-ion batteries, for their unique two-dimensional structure, tunable surface chemistry, and excellent electrical conductivity. Recently, Nb2CTx, as a new type of MXene, has attracted more and more attention due to its high theoretical specific capacity of 542 mAh g–1. However, the preparation of few-layer Nb2CTx nanosheets with high-quality remains a challenge, which limits their research and application. In this work, high-quality few-layer Nb2CTx nanosheets with a large lateral size and a high conductivity of up to 500 S cm–1 were prepared by a simple HCl-LiF hydrothermal etching method, which is 2 orders of magnitude higher than that of previously reported Nb2CTx. Furthermore, from its aqueous ink, the viscosity-tunable organic few-layer Nb2CTx ink was prepared by HCl-induced flocculation and N-methyl-2-pyrrolidone treatment. When using the organic few-layer Nb2CTx ink as an additive-free anode of lithium-ion batteries, it showed excellent cycling performance with a reversible specific capacity of 524.0 mAh g–1 after 500 cycles at 0.5 A g–1 and 444.0 mAh g–1 after 5000 cycles at 1 A g–1. For rate performance, a specific capacity of 159.8 mAh g–1 was obtained at a high current density of 5 A g–1, and an excellent capacity retention rate of about 95.65% was achieved when the current density returned to 0.5 A g–1. This work presents a simple and scalable process for the preparation of high-quality Nb2CTx and its aqueous/organic ink, which demonstrates important application potential as electrodes for electrochemical energy storage devices.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
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IF 5.316
Krishnamoorthy Rajavel,Xuecheng Yu,Pengli Zhu,Yougen Hu,Rong Sun,Chingping Wong
Tunable Electromagnetic Interference (EMI) shielding behaviors of 2D MXene (Nb 2 CT x ) were explored via different exfoliation conditions. Stacked, lamellar few-layer, oxygen-related surface functional groups, and structural defects along with oxidative products of Nb 2 CT x were identified by tuning chemical etching conditions during one-step exfoliation process. Exfoliation of Nb 2 CT x with a tightly packed stacked structure remarked at lower etching times. The unpacking of Nb 2 CT x into lamellar morphology followed by separated few-layer Nb 2 CT x remarked at moderate etching time, whereas structural misalignment, defects, and oxidation of Nb 2 CT x occurred during prolonged chemical etching times. Synergistic effect of one-step extracted few-layers and lamellar structured Nb 2 CT x favorably enrich the assembly of multiple electrical conductive pathways responsible for absorption dominated EMI shielding performance in X- and Ku-band region. The assembled wax nanocomposites with 80% of Nb 2 CT x loading exfoliated at 100 h etching time at a thickness of 1 mm exhibited EMI shielding effectiveness of about 44.09 ± 1.99 dB at 12 GHz, and its EMI attenuation mechanism explained by conduction and eddy current loss. The combined action of few-layer and lamellar Nb 2 CT x nanostructures could be interesting for making novel shielding materials; open a new avenue for niobium series in the MXene family for elaborated applications.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
高影响因子
TALANTA
·
2024
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IF 5.6
Deshou Xiong,Manyu Luo,Qing He,Xingpeng Huang,Sijin Cai,Shuang Li,Zhenhong Jia,Zhixian Gao
The detection of ammonia (NH 3 )gas holds significant importance in both daily life and industrial production. In this study, the Nb 2 CT x /MoSe 2 sensor was synthesized using a one-step hydrothermal method and applied for NH 3 detection. The morphology and elemental composition of the composites were analyzed through a series of characterization techniques including XRD, TEM, SEM, and XPS, confirming the successful synthesis of Nb 2 CT x /MoSe 2 composite with the optimal mass ratio. The sensing performance of the sensor for NH 3 (0.1–100 ppm) was tested at room temperature (∼25 °C). The results showed that, compared to pure Nb 2 CT x , the sensor based on Nb 2 CT x /MoSe 2 composite exhibited more stable baseline resistance, a 3.5-fold increase in response to 50 ppm NH 3 , and a reduction in response/recovery time by 56.4 s/32.1 s. Additionally, the sensor's response to NH 3 (1 ppm, 50 ppm, 100 ppm) varied by less than 10 % over 90 days, demonstrating excellent stability. The sensing mechanism of NH 3 by Nb 2 CT x /MoSe 2 composite is attributed to the formation of a p-n heterojunction and surface charge transfer at the interface between p-type Nb 2 CT x and n-type MoSe 2 . Finally, the superior selectivity mechanism of the composite for NH 3 was investigated using first-principles calculations. This work opens a new avenue for exploring the application potential of Nb 2 CT x MXene-based nanocomposites in NH 3 detection.
研究领域:
材料科学
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传感器技术
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纳米技术
✓ 已验证
DOI
PubMed
高影响因子
Biomedical Optics Express
·
2021
·Vol. 12
·期 11
·7051-7063
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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.
研究领域:
光学
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环境科学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
Journal of Food Measurement and Characterization
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2024
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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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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
·
IF 9.4
Ting Wang,Weifang Zhao,Ran Ren,Huilin Lan,Tengfei Zhou,Juncheng Hu,Qingqing Jiang
Exploring robust electrode materials which could permit fast and reversible insertion/extraction of large K + is a crucial challenge for potassium-ion batteries (PIBs). Smart interfacial design could facilitate electron/ion transport as well as assure the integrity of electrode. Herein, Cetyltrimethylammonium bromide (CTAB) was found to play bifunctional roles in construction of Nb 2 CT x @MoSe 2 heterostructure. Firstly, functionalization of CTAB on the surface of Nb 2 CT x could influence the subsequent growth of MoSe 2 by electrostatic effect, stereochemical effect and the synergetic Lewis acid-base interaction, leading to the formation of Nb 2 CT x @MoSe 2 with tiled heterostructure. Secondly, the interlayer spacing of Nb 2 CT x was expanded from 0.77 to 1.21 nm owing to the pillar effect of CTAB. As excepted, the capacity retention was 80 % from 100 mA g −1 (406 mA h g −1 ) to 1000 mA g −1 concerning rate capability and the specific capacity maintained at 240 mA h g −1 (at 2000 mA g −1 ) over 300 cycles. The calculated D K values from Galvanostatic intermittent titration technique (GITT) measurement of the titled C-T-Nb 2 CT x @MoSe 2 @C electrode is two orders of magnitude larger than the traditional T-Nb 2 CT x @MoSe 2 @C electrode, further confirming intimate interface between MoSe 2 and Nb 2 CT x could provide convenient potassium-ion transport channels and fast diffusion kinetics. Finally, ex-situ characterizations at different charging and discharging voltage stages, including ex-situ XRD/Raman/HRTEM/XPS have been carried out to reveal the potassium storage mechanism. This work provides a facile strategy for the regulation of interface engineering by the assist of CTAB which could extend to other MXenes-TMDs (Transition metal dichalcogenides) hybrid electrodes.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
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2024
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IF 5.1
Jizhong Deng,Ping Zhao,Zhiyi Wu,Yuanyu Wang
Flexible high-performance piezoelectric nanogenerator (PENG) excel in converting mechanical energy into electrical energy and exhibit remarkable sensitivity, a feature that is paramount for the development of self-driven piezoelectric sensors . In this study, electrospinning technology was used to prepare poly (vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] based piezoelectric nanofiber composite films containing potassium-sodium niobate nano particles (KNN NPs) and Nb 2 CT x co-doping, as well as single-component doping. The co-doped composite film attained an optimal β-phase content of 91.33%. Owing to the enhanced dipole alignment and interface charge polarization, the piezoelectric performance of the co-doped composite film was significantly enhanced compared to that of single-component doping. The co-doped piezoelectric composite film displayed a stable maximum output voltage of 20 V and an output current of 1.46 μA. The peak instantaneous power output was measured at 9.9 μW under the optimal resistive load of 10 MΩ. Durability testing over 2000 cycles affirmed the excellent mechanical stability of the piezoelectric composite film. Moreover, the fabricated piezoelectric composite film showed considerable potential in applications such as monitoring human activities and serving as an early warning system for natural disasters such as landslides, as indicated by the test results.
研究领域:
材料科学
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能源技术
·
传感器技术
✓ 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）