SENSORS AND ACTUATORS B-CHEMICAL
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2017
·
IF 5.401
Hanqiang Zhang,Yihong Huang,Xiahui Lin,Fenfen Lu,Zhusen Zhang,Zhibiao Hu
A facile synthesis of lanthanum (La) loaded graphitic carbon nitride nanosheets (CNNS) was developed in this study. The obtained La-CNNS exhibited an intense emission peak at 255 nm, owing to fluorescence enhancement effect of introduced La on the surface of CNNS. La-CNNS showed excitation-independent behavior and blue shift compared with CNNS. It displayed great fluorescence quenching via photoinduced electron transfer (PET) when a small amount of Fe 3+ was added. The probe exhibited a wide linear response concentration range (0.1–20 μM) to Fe 3+ with a detection limit of 0.0232 μM. The La-CNNS fluorescence probe was highly selective and suitable for Fe 3+ analysis in natural water samples.
研究领域:
材料科学
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分析化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
·
IF 5.518
Yongqiang Wang,Mengdan Zhang,Jiamei Zhao,Chen Chen,Yingying Zhou,Xin Zheng,Conglu Zhang
The energy storage and upconversion effect of carbon quantum dots (CQDs) could improve the photocatalytic efficiency of materials. In this study, a visible-light-driven photocatalyst , CQDs-doped carbon nitride nanosheets composite (CNS/CQDs) was in-situ synthesized by the thermal stripping of carbon nitride bulk (CNB). The as-prepared CNS/CQDs photocatalyst was systematically characterized and applied to the removal of Meloxicam (Mel) in water. The results showed that the introduction of CQDs could improve the visible light utilization of the carbon nitride. Mel (50 mL, 10 mg L −1 ) was degraded by 99.60% in 45 min with CNS/CQDs (20 mg). The stability and recycling experiments showed that CNS/CQDs could maintain high photocatalytic activity under complex matrix and multiple cycles. This work will provide a new attempt to synthesize the CQDs doped photocatalytic materials for the effective removal of organic pollutants in water under visible light.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2023
·
IF 3.8
Jie Zhang,Tianyang Cui,Zhaoxin Li,Ruixia Gao,Xuemeng Tian,Chaochao Dong,Junling Wang,Wei Cai,Yuan Hu
The incompatible interface between carbon nitride (CN) nanosheets and polymer resin is a huge challenge to develop high-performance polymer/CN nanocomposites. Recently, the complicated surface functionalization methods reported severely hinder the commercial production and practical application of polymer/CN nanocomposites. Herein, conducted by the first-principles calculations, a simple surface engineering is put forward to change the surface characteristic of CN nanosheets by rapidly introducing oxygen atoms with a chemical oxidation method. Presented by the first-principles calculations, it is found that the introduction of oxygen atoms can enhance the adsorption energy between oxygen-doping carbon nitride nanosheets (OCN) and waterborne polyurethane (WPU) resin. As a result, a stronger interfacial interaction and better dispersion state are presented in WPU/OCN nanocomposites, thus laying the foundation for the properties enhancement. Further, effective suppression effects for thermal pyrolysis and fire hazards of WPU resin are demonstrated by OCN nanosheets. As presented by cone calorimeter results, the peak values of heat release rate and total heat release in WPU/OCN-2 are decreased to 806 kW/m 2 and 43.3 MJ/m 2 , significantly less than those of pure WPU (1028 kW/m 2 and 55.9 MJ/m 2 ). Meanwhile, more char residue, lower signal intensity of pyrolysis gas, and a prolonged time for signal peak also confirm that the addition of 2.0 wt% OCN nanosheets can hinder the thermal degradation behavior of WPU resin. In addition, the introduction of oxygen atoms promotes the formation of hydrogen bond interactions between OCN nanosheets and WPU matrix, thus enhancing interfacial compatibility and overcoming the re-stack problem. As a result, break strength and elongation at break of WPU/OCN-2 are up to 621% and 24.4 MPa, respectively. The combination of first-principles calculations and surface engineering opens a new approach for designing and developing high-performance polymer nanocomposites .
研究领域:
材料科学
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计算化学
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产品关联
DOI
高影响因子
Catalysts
·
2018
·Vol. 8
·期 9
·366
·
IF 3.465
Hongwei Wang,Guiqing Huang,Zhiwei Chen,Weibing Li
In this study, we prepared carbon self-doped carbon nitride nanosheets through a glucose synergic co-condensation method. In the carbon self-doped structure, the N atoms in the triazine rings were substituted by C atoms, resulting in enhanced visible-light photocatalytic hydrogen production, which is three-times higher than that of bulk carbon nitride. The enhanced photocatalytic hydrogen production was attributed to the higher charge-carrier transfer rate and widened light absorption range of the carbon nitride nanosheets after carbon self-doping. Thus, this work highlights the importance of carbon self-doping for improving the photocatalytic performance. Meanwhile, it provides a feasible method for the preparation of carbon self-doped carbon nitride without destroying the 2D conjugated backbone structures.Keywords:carbon nitride nanosheets;carbon self-doping;photocatalytic hydrogen production;charge transfer rate
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
·
IF 9.965
Anran Zhang,Yang Guo,Hao Xie,Yangping Zhang,Yunzhi Fu,Changqing Ye,Yukou Du,Mingshan Zhu
The application of graphite carbon nitride photocatalysts is hampered by their low specific surface areas, few active sites, and low photogenerated electron-hole transfer rates. Here, we report a green and controllable strategy for synthesizing kelp-like carbon nitride nanosheets through self-assembled materials prepared from melamine and trithiocyanuric acid using sonochemistry. The prepared carbon nitride nanosheets showed superior and long-lasting photocatalytic activity in hydrogen evolution and the degradation of tetracycline hydrochloride. The significantly enhanced photocatalytic performance of carbon nitride nanosheets is attributed to the curled porous nanosheet structure and the appropriate amount of O-doping. This work provides a new design strategy for preparing shape-controlled carbon nitride catalysts via a green, fast, sonochemically mediated self-assembly approach.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Qi Li,Xiaoyan Wang,Hongjiang Ge,Dongping Li,Yang Cao,Dejun Sun
As a novel enhanced oil recovery (EOR) technology, nanofluid flooding has become a research hotspot in recent years. However, the current nanofluid flooding technologies face certain limitations, particularly at low particle concentrations. Compared with the conventional homogeneous spherical nanoparticles, amphiphilic nanosheets exhibit higher interfacial activity and variable shapes, making them more promising for EOR applications. This article prepared a nanofluid based on amphiphilic carbon nitride (ACN) nanosheets and studied its physicochemical properties and EOR potential. The results showed that the ACN nanosheets exhibit an obvious lamellar morphology with a transverse size in the range of several hundred nanometers. Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA) revealed that the ACN nanosheets possess amphiphilic properties due to the presence of uncondensed amino and hydroxyl groups at the edges. Water contact angle measurements confirmed the nanosheets’ water-wet behavior. Notably, this amphiphilicity enables the nanosheets to disperse in various polar solvents, reduce the oil–water interfacial tension, and enhance the oil–water interfacial film strength in saline environments. The Zeta potential (ζ) of the 0.01 % ACN nanofluid was −50.8 mV in a neutral environment, proving that it has high colloidal stability. A static imbibition experiment revealed that the imbibition recovery rate increased by 15.75 % at 0.01 % ACN nanofluid, while a core displacement test showed an EOR of 19.21 %. The ACN nanosheets can form a high-strength elastic climbing film at the oil–water interface, which may play an important role in the EOR mechanism. This study provides a new cost-effective nanofluid system for EOR, demonstrating promising application potential.
研究领域:
石油工程
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材料科学
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Energy & Fuels
·
2019
·Vol. 3
·期 7
·1764-1775
·
IF 4.912
Islam A. Abdelhafeez,Qiufang Yao,Cixuan Wang,Yiming Su,Xuefei Zhou,Yalei Zhang
Fabrication of few-layered polymeric carbon nitride (PCN) photocatalysts have attracted increasing attention owing to their substantial enhancement of the photocatalytic performance. A green strategy for the synthesis of ultrathin PCN nanosheets with integration of high-efficiency and enriched active edges using minimimal chemicals and energy input is overwhelmingly required and is still challenging. Herein, we report a green, cost-effective and template-free synthesis approach for ultrathin foam-like PCN nanosheets with enriched active sites in a wet atmosphere via a “three-in-one” strategy. This strategy relies on coupling of melem segments, polymerization with condensed layers, delamination by water molecules, and introduction of new terminal groups entirely in one-pot without any other additives. The obtained melem-derived PCN (MFCN-wet) shows highly loose and extremely light characteristics with the formation of ultrathin few-layers. Furthermore, it exhibits a high specific surface area and pore volume. Most importantly, the enriched active sites with fast charge carrier transfer drastically enhance the hydrogen evolution rate and rhodamine B (RhB) degradation with a high stability under visible light irradiation, compared with that of the as-synthesized materials in nitrogen and air atmospheres. This sustainable strategy could provide new opportunities for further environmental and energy applications.
研究领域:
材料科学
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环境科学
·
能源科学
✓ 已验证
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2020
·
IF 7.635
Yanyan Wang,Xian Zhang,Xin Ding,Ping Zhang,Mengting Shu,Qian Zhang,Yi Gong,Kang Zheng,Xingyou Tian
Owing to the unique layered structure, abundant functional groups and appropriate band gap, carbon nitride nanosheets (CNNS) has captured extensively attention in photocatalytic pollutants degradation and hydrogen evolution , while few study has been focused on improving the thermal conductivity . Considering its graphene-like network that is confined to 2D atomic thickness, CNNS would also show desirable thermal conductivity due to the highly aligned atoms decreasing phonon scattering. Here, CNNS is first used to improve the thermal conductivity of polyimide (PI) film. Based on the orientation of PI molecules during imidization and strong interaction with PI, CNNS realize in-plane self-orientation during solvent evaporation to form continuous thermal pathway in PI film. The thermal conductivity of PI/CNNS nanocomposite films reach 2.04 Wm −1 K −1 with relatively low CNNS loading (20 wt%) which is about eleven times of the corresponding pure PI (0.18 Wm −1 K −1 ). Furthermore, the potential application of the PI/CNNS nanocomposite films for effective heat dissipation is explored by experiments and simulation. Meanwhile, the PI/CNNS nanocomposite films keep superior electrical insulation property and thermal stability. This work expands the application of CNNS and provides a facile, efficient approach to the design of high thermal conductive materials .
研究领域:
材料科学
·
热管理技术
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 12
·1-9
·
IF 5.479
Shi Jianrong,Li Geyuan,Cui Yanru,Zhang Yan,Liu Donghao,Shi Yi,He Hua
β-Cyclodextrin-functionalized carbon nitride nanosheets were modified with a molecularly imprinted polymer to obtain a fluorescent probe of type MIP@β-CD/CNNS which is shown to enable fluorometric determination of sterigmatocystin (STG). The material was characterized by transmission electron microscopy, infrared spectra, powder X-ray diffraction, X-ray photoelectron spectroscopy, and by absorption and emission spectra. The modified CNNSs have a good fluorescence quantum yield (13%), high sorption capacity for STG (86 mg·g −1 ), fast adsorption rate (25 min), and superior adsorption selectivity (with an imprint factor 2.56). When used as an optical probe for STG, the CNNSs act as the chromophore, while β-CD and MIP act as the recognition groups. The blue fluorescence of MIP@β-CD/CNNS (with excitation/emission maxima at 368/432 nm) is quenched by STG. Fluorescence drops linearly in the 0.15 to 3.1 μM STG concentration range. The lower detection limit is 74 nM. The method was successfully applied to the determination of STG in spiked wheat extract. Conceivably, this detection scheme based on a combination of β-CD inclusion and molecular imprinting may be extended to the detection of various other organic compounds.
Schematic representation of the preparation of surface-imprinted β-cyclodextrin-functionalized carbon nitride nanosheets. These are used, along with a molecularly imprinted polymer, for fluorometric determination of sterigmatocystin.
研究领域:
分析化学
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食品安全
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2019
·Vol. 29
·期 49
·1905576
·
IF 15.621
Dan Han,Dongya Ni,Qing Zhou,Jingjing Ji,Yanqin Lv,Yanfei Shen,Songqin Liu,Yuanjian Zhang
Rapid screening of polycyclic aromatic hydrocarbons (PAHs), a large class of toxic and carcinogenic compounds, is highly desirable for environmental and food safety. In principle, a photoluminescent (PL) assay is a potential route, but demands highly efficient and stable, low cost, and environment-friendly photoactive materials. 2D carbon nitride nanosheets (CNNS) that have triggered increasing interest may meet all these requirements. However, conventional applications of CNNS are restricted in aqueous solution, in which the long-term dispersibility is difficult to be addressed. Here, the harnessing of unique PL properties of CNNS is reported by dispersing them in a hierarchical polymeric matrix, driven by electrostatic interactions. Such a configuration not only enables a solid-state host to perpetually maintain homogeneous dispersibility of CNNS but also processes free channels for sufficient mass transfer. Moreover, the nanohybrid inherits the unique PL properties of CNNS. Further using β-CD as the molecular recognition unit, an economic, highly selective and sensitive paper-based PL sensor for PAHs is constructed via an inner-filter effect. This work opens a new avenue in harnessing unique PL properties of CNNS in solid state with superior stability for a variety of potential sensing applications, especially for point-of-care testing and/or in developing countries.
研究领域:
环境科学
·
材料科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Jianjian Yi,Xiaojie She,Yanhua Song,Mao Mao,Kaixiang Xia,Yuanguo Xu,Zhao Mo,Jingjie Wu,Hui Xu,Huaming Li
To date, despite significant achievements in noble-metal co-catalysts, it is still challenging to develop high-performance noble-metal-alternative co-catalysts for economic hydrogen production. In this work, we demonstrate that the metallic 1T-WS 2 obtained through a facile solvothermal method can function as co-catalyst for boosting the photocatalytic hydrogen production with the merits below: (i) noble-metal-free; (ii) excellent electrical conductivity; (iii) extra active sites on basal plane rather than edge sites for H 2 generation. As demonstrated in photocatalytic hydrogen evolution, the designed composite using two-dimensional carbon nitride (2D-C 3 N 4 ) as semiconductor and 1T-WS 2 as co-catalyst (1T-WS 2 /2D-C 3 N 4 ) exhibits giant enhancement, in comparison with the bare 2D-C 3 N 4 and 2H-WS 2 /2D-C 3 N 4 . This work highlights the surface engineering strategy of co-catalysts such as phase engineering for promoting the photocatalytic performance.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Zhentao Zhou,Kexin Li,Wenying Deng,Jun Li,Yinhua Yan,Yawen Li,Xiaoke Quan,Tong Wang
Polymeric materials are promising candidates as photocatalysts for environmental purification, however their catalytic performance are still unsatisfactory mainly due to the strong Coulomb interactions between electron and hole that leads to fast charge recombination. Herein, taking graphitic carbon nitride as an example, we verify that installing carbon nitride nanosheets with nitrogen vacancy could break the intrinsic electronic state distribution, forming energy disordered interfaces around the vacancies with the energy difference as large as 0.35 eV. Such a large energy difference is found energetic enough to overcome the strong Coulomb interactions between electron and hole for hot electron and hole generation, as a result showing high electron-hole separation efficiency. Benefited from these advantages, the as prepared material shows remarkable photocatalytic performance toward organic pollutants degradation. The improved catalytic performance is originated from the promoted exciton dissociation that leads to ultra high hydroxyl radical generation. This study offers a new understanding of the excitonic effects for designing advanced polymeric photocatalyst for energy and environment related applications.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）