Journal of Materials Chemistry C
·
2016
·Vol. 4
·期 16
·3415-3421
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IF 5.066
Haiqin Wu,Lan Jin
In this study, new facile, economical and fluorescent ultrathin films (UTFs) for detection of tiopronin are developed. The UTFs have been fabricated by combining the alizarin red S–boric acid adduct (ARS–H3BO3) with MgAl layered double hydroxide (LDH) nanoparticles through the layer-by-layer (LBL) assembly technique. UV-vis, fluorescence spectroscopy, XRD, SEM and AFM have been adopted to monitor the assembly process. The UTFs display a uniform morphology and a periodic layered structure. Using ARS as a probe, which does not emit fluorescence by itself but displays fluorescence when complexed with boron, the assembled ARS–H3BO3/LDH UTFs display a high luminescence response to tiopronin. In the presence of Cu2+, the fluorescence of UTFs was quenched, which is attributed to the complexation between Cu2+ and ARS. Upon adding tiopronin to the UTF–Cu system, tiopronin would form a complex with Cu2+ preferentially, leading to the increased fluorescence of UTFs. Based on the above mechanism, a turn-on fluorescent ensemble for tiopronin is developed. A linear response was obtained in the range of 0–80 ng mL−1, with a detection limit of 0.47 ng mL−1. Compared with ARS and other analytes, the tighter binding of tiopronin to Cu2+ led to an assay with high specificity. Therefore, this work provides a facile LBL strategy for the fabrication of a solid state sensor based on ARS dye for detection of tiopronin.
研究领域:
分析化学
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材料科学
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生物医学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Jianing Liu,Yi Huang,Ying Chen,Haobo Ke,Qian Deng,Hua Tang,Jinyan Yang,Shijun Ni
With industry development, water contaminated with vanadium(V) has attracted increasing attention. Various adsorbents have been used to remove V(V); however, reducing V(V) to V(III) or V(IV) with low solubility and toxicity remains a challenge. Herein, a novel layered double hydroxide loading with polyaniline composites (PANI-LDHs) adsorbent was prepared to facilitate V(V) detoxification and elimination. We examined the physicochemical characteristics and confirmed the successful formation of the composite. Some key experimental parameters were evaluated in detail for their potential impact on V(V) removal. The calculated maximum adsorption capacity was 222.22 mg/L with a dosage of only 0.3 g/L under 318 K, which was higher than other adsorbents. More importantly, about 80 % of the absorbed V(V) was reduced and detoxified by reductive nitrogen-containing groups in PANI. In addition, the PANI-LDHs can effectively resist the interference of various coexisting ions. The excellent V(V) removal performance is mainly attributed to the high stability of the inorganic skeleton (LDH) and the high chemical activity of PANI. Dynamics and thermodynamic analysis were also used to study the V(V) adsorption behavior. Finally, the mechanism study suggested that V(V) anions were adsorbed onto the surface of PANI-LDHs via electrostatic attraction or the H-bonding. The adsorbed V(V) was subsequently reduced and immobilized to V(IV) and V(III) oxides by nitrogen-containing groups in PANI, thus achieving the detoxification and removal of V(V). The combination of adsorption and detoxification properties, high adsorption capacity, and good selectivity make PANI-LDHs an ideal candidate for V(V)-containing wastewater treatment.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
APPLIED CLAY SCIENCE
·
2024
·
IF 5.3
Aihua Xiang,Yifan Li,Kun Liu,Xin Wang,Tuanliu Hu
Selenium (Se) is a beneficial plant micronutrient, and the application of Se fertilizers can promote plant growth and enhance the Se content in crops. However, traditional soluble Se fertilizers have low utilization efficiency of Se due to adsorption or leaching. Here, selenite (SeO 3 2− ) -intercalated Mg/Al layered double hydroxide (Se-Mg/Al) for SeO 3 2− slow-release was synthesized by co-precipitation and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Se-Mg/Al possessed a typical lamellar structure, combining with selenite by electrostatic interaction in interlayer and chemisorption on the surface. The release mechanism of selenite in distilled water from Mg/Al layered double hydroxide (Mg/Al LDH) was Fickian diffusion with gradually released 97.86% after 20 h (Over 90% within 2 h for sodium selenite). At pH range 4.0–8.0, Se-Mg/Al had a stable slow-release ability. And, the sulfate and phosphate anions could effectively trigger the release of selenite through anions exchange. The pot experiments showed that Se-Mg/Al increased Se content of vegetables, more than twice that of directly using sodium selenite. Compared with control treatment, the average stem height and fresh weight per 10 plants with Se-Mg/Al treatment improved approximately 1.48 times and 2.34 times, respectively. This work provides a feasible way for achieving crops selenium supplementation and improving selenium utilization efficiency.
研究领域:
农业科学
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植物营养学
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DOI
高影响因子
Journal of Energy Storage
·
2025
·
IF 9.8
Disong Wang,Xiaohui Guan,Liu Yang,Baoyang Tian,Jiqing Zhang,Ruotong Li,Tao Zou,Penggang Yin,Guangsheng Wang
Layered double hydroxides (LDHs) are regarded as a promising electrode material for supercapacitors. Nevertheless, their large-scale application is impeded by several drawbacks, such as low electronic conductivity, limited electroactive sites, and poor cycling stability. Two-dimensional titanium-based carbide (Ti 3 C 2 T x ) loading NiCoCu-based layered double hydroxide heterostructures (Ti 3 C 2 T x @NiCoCu-LDH), which feature a layered and cross-linked network, were prepared to improve the electrochemical performance of NiCoCu-LDH. The layered network structure of Ti 3 C 2 T x @NiCoCu-LDH enhances active site exposure and accommodates volume changes during cycling. Both the specific capacitance and structural stability of the electrode are improved. Additionally, Ti 3 C 2 T x boosts the electronic conductivity of LDHs and accelerates the kinetics of electrochemical reactions. Ti 3 C 2 T x @NiCoCu-LDH exhibits a high specific capacity of 1891.4 F·g −1 (262.2 mAh·g −1 ) at 1 A·g −1 and exceptional cycling stability. When assembled into Ti 3 C 2 T x @NiCoCu-LDH//activated carbon (AC) hybrid supercapacitor, it demonstrates a high energy density of 35.5 Wh·kg −1 at 826.8 W·kg −1 . In addition, the supercapacitor maintains 81.6 % of initial capacitance after 20,000 cycles. This work has proposed a promissing MXene-based composite cathode for high-performance hybrid supercapacitors.
研究领域:
材料科学
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电化学
·
储能
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纳米技术
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无机化学
✓ 已验证
DOI
高影响因子
MOLECULES
·
2024
·
IF 4.2
Fengrong Zhang,Cuilan Zhang,Kaixuan Zhang,Lishun Wu,Dandan Han
Heavy metals and organic pollutants are prevalent in water bodies, causing great damage to the environment and human beings. Hence, it is urgent to develop a kind of adsorbent with good performance. Anion interlacing layered double hydroxides (LDHs) are a promising adsorbent for the sustainable removal of heavy metal ions and dyes from wastewater. Using aluminum chloride, zinc chloride and ammonium pentaborate tetrahydrate (NH 4 B 5 O 8 · 4H 2 O, BA) as raw materials, the LDHs complex (BA-LDHs) of B 5 O 8 − intercalation was prepared by one-step hydrothermal method. The BA-LDHs samples were characterized by a X-ray powder diffractometer (XRD), scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR) and the Brunauer–Emmett–Teller (BET) method. The results showed that B 5 O 8 - was successfully intercalated. Adsorption experimental results suggested that BA-LDHs possess a maximum adsorption capacity of 18.7, 57.5, 70.2, and 3.12 mg·g −1 for Cd(II), Cu(II), Cr(VI) and Methylene blue (MB) at C s = 2 g·L −1 , respectively. The adsorption experiment conforms to the Langmuir and Freundlich adsorption models, and the kinetic adsorption data are well fitted by the pseudo-second-order adsorption kinetic equation. The as-prepared BA-LDHs have potential application prospects in the removal of heavy metals and dyes in wastewater. More importantly, they also provide a strategy for preparing selective adsorbents.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
Gels
·
2022
·Vol. 8
·期 9
·581
·
IF 4.432
Mengtian Sun,Yang Wang,Xiaowu Wang,Qiong Liu,Ming Li,Yury M. Shulga,Zhi Li
To adjust the thermal safety of hydrophobic silica aerogel, layered double hydroxide (LDH)/silica aerogel (SA) composites were prepared by an in-situ sol-gel process at ambient pressure. This study found the physical combination of SA and MgAl-LDH based on the FTIR spectra and phase composition of LDH/SA. The N2sorption analysis confirms that the introduction of MgAl-LDH does not change the mesoporous attribution of LDH/SA significantly. With the increase in MgAl-LDH addictive content, the low density (0.12–0.13 g/cm3), low thermal conductivity (24.28–26.38 mW/m/K), and large specific surface area (730.7–903.7 m2g) of LDH/SA are still maintained, which can satisfy the requirements of thermal insulation. The TG-DSC analysis demonstrates that the endothermic effects and metal oxides formed during the MgAl-LDH decomposition are beneficial to the improvement of the thermal stability of LDH/SA composites. In addition, it was found that the gross calorific values of LDH/SA composites decrease with an increase in MgAl-LDH addictive content, all of which are lower than that of the pure SA. The research outcomes indicate that the thermal safety of LDH/SA composites is enhanced significantly by doping MgAl-LDH without impairing too many of the excellent properties, which benefits their expansion in the thermal insulation field.Keywords:silica aerogel;layered double hydroxide;thermal properties;structure
研究领域:
材料科学
·
热力学
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产品关联
DOI
PubMed
高影响因子
Biomaterials Science
·
2018
·Vol. 6
·期 5
·1227-1237
·
IF 5.831
Qianwen Li,Donghui Wang,Jiajun Qiu,Feng Peng,Xuanyong Liu
Hard tissue implant materials which can cause a suitable alkaline microenvironment are thought to be beneficial for stimulating osteoblast differentiation while suppressing osteoclast generation. To make the local pH around the interface between materials and cells controllable, we prepared a series of Mg–Fe layered double hydroxide (LDH) films on acid-etched pure titanium surfaces via hydrothermal treatment. By adjusting the Mg/Fe proportion ratio, the interlayer spacing of Mg–Fe LDHs was regulated, making their OH− exchange abilities adjustable, and this ultimately resulted in a microenvironment with a controllable pH value. In vitro experiments demonstrated that the Mg–Fe LDH film-modified titanium surface possessed good biocompatibility and osteogenic activity, especially the Mg–Fe LDH film with Mg/Fe proportion ratio of 4, which could form a suitable alkaline microenvironment for the growth and osteogenetic differentiation of stem cells. These results demonstrate the potential application of the prepared Mg–Fe LDH films in enhancing the osteogenesis of implant materials while providing a new way into the design of controllable alkaline environment.
研究领域:
生物材料学
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细胞生物学
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医学工程
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2020
·
IF 7.539
Huabin Wang,Siqi Wang,Zhulei Chen,Xinquan Zhou,Jia Wang,Zhuqi Chen
Cationic and anionic heavy metal contaminants generally co-exist in practical industrial effluent, and simultaneously removal of these species is a bottleneck for most of the bio-adsorbents because of their contrary charge. In this work, pinewood sawdust derived engineered biochar (BC) was fabricated with MgAl layered double hydroxide (MgAl-LDH) nanosheets, which could efficiently and simultaneously capture heavy metal cations and oxyanions from wastewater. The synergetic effect between loaded MgAl-LDH and BC substantially improves its adsorption performance towards both cationic and anionic contaminants, i.e., Pb 2+ and CrO 4 2− . The adsorption capacity of MgAl-LDH/BC for Pb 2+ reached 591.2 mg/g, which is 263% higher than that of BC, and in the case of CrO 4 2− , the adsorption capacity is 330.8 mg/g, 416% higher than that of BC. The elimination of Pb 2+ was mainly attributed to forming complexations with surface functional groups. While for oxyanions removal, CrO 4 2− can be reduced to Cr 3+ by functional groups, and then generated Cr 3+ could replace Al 3+ via morphic substitution, consequently formed an MgCr-LDH structure. Further, in the continuous fixed-bed column study, 225 bed volume of simulating electroplating wastewater co-existed with Pb 2+ and CrO 4 2− can be efficiently treated. Hence, this study sheds light on the engineered biochar design to efficiently and simultaneously capture heavy metal cations and oxyanions and its feasibility on real wastewater purification.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Catalysts
·
2021
·Vol. 12
·期 1
·42
·
IF 4.146
Longxin Ju,Gang Li,Hongxian Luo
Aldol condensation reactions are very important C–C coupling reactions in organic chemistry. In this study, the catalytic performance of layered double hydroxides (LDHs) in the aldol condensation reaction of formaldehyde (FA) and propionaldehyde (PA) was investigated. The MxAl-LDHs (denoted as re-MxAl–LDHs; M = Ca and Mg; X = 2–4), as heterogeneous basic catalysts toward the aldol condensation reaction, were prepared via a two-step procedure. The catalyst exhibited a high PA conversion (82.59%), but the methacrolein (MAL) selectivity was only 36.01% due to the limitation of the alkali-catalyzed mechanism. On this basis, the direct intercalation of L-proline into LDHs also has been investigated. The influences of several operating conditions, including the temperature, reaction time, and substrate content, on the reaction results were systematically studied, and the optimized reaction conditions were obtained. The optimized Mg3Al–Pro-LDHs catalyst exhibited a much higher MAL selectivity than those of re-MgxAl–LDHs.Keywords:layered double hydroxides;L-proline;aldol condensation reaction
研究领域:
有机化学
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催化材料科学
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DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 12
·2537
·
IF 2.467
Lin Chi,Zheng Wang,Youfang Zhou,Shuang Lu,Yan Yao
In this study, the chloride adsorption behaviors of CaAl-Cl LDH precursors with various Ca:Al ratios were investigated. The optimal chloride ion removal rate was 87.06% due to the formation of hydrocalumite. The chloride adsorption products of CaAl-Cl LDH precursors were further characterized by X-ray diffraction analysis and atomic structure analysis, the adsorption mechanism was considered to be co-precipitate process. The chloride adsorption behaviors of cementitious materials blended with CaAl-Cl LDH precursors were further investigated. Leaching test according to Test Code for Hydraulic Concrete (SL352-2006) was performed to testify the stability of chloride ions in the mortar. The results show that more than 98.3% chloride ions were immobilized in cement mortar blended with CaAl-Cl LDH precursor and cannot be easily released again. The inhibition performance of steel in the electrolytes with/without CaAl LDH precursor was investigated by using electrochemical measurements. The results indicate that CaAl LDH precursor can effectively protect the passive film on steel surface by chloride adsorption. Considering the high anion exchange capacities of the LDHs, synthesized chloride adsorbent precursor can be applied as new inhibitors blended in cementitious materials to prevent the chloride-induced deterioration. Moreover, the application of chloride adsorption on CaAl-Cl LDH could also be of interest for the application of seawater blended concrete.Keywords:layered double hydroxides;chloride ion adsorption;corrosion inhibitor
研究领域:
材料科学
·
土木工程
·
防腐蚀研究
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2020
·
IF 5.006
Peng Zhang,Ziyan Wang,Yan Zhang,Jian Wang,Wenqing Li,Lina Li,Peiping Zhang,Cundi Wei,Shiding Miao
In this work a Pd/Fe-Co-Ni layered double hydroxide (LDH) composite was prepared and investigated in the semi-hydrogenation of 2-methyl-3-butyn-2-ol (MBY). Hollow nanocages of ternary Fe-Co-Ni LDH were constructed by stacking the LDH nanosheets edge-to-face which inherited the rhombic dodecahedral structure of ZIF-67 templates. Uniform palladium (Pd) nanocrystals with cubic shapes were imbedded in the LDH nanocages via a solvothermal method. The hydroxyl groups on LDH supports were critical to inhibit the association of excess hydrogen atoms on the catalyst, so less MBY molecules were converted to 2-methyl-2-butanol (MBA) during the hydrogenation catalysis. Under optimized reaction conditions the hydrogenation activity of Pd/Fe-Co-Ni LDH was significantly improved, and the conversion of MBY was higher than 99% with selectivity of 2-methyl-3-buten-2-ol (MBE) exceeding 99%. The catalyst was easily recovered and had little reduction in catalytic performance during the cycling reactions.
研究领域:
化学工程
·
催化科学
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产品关联
DOI
高影响因子
ChemistrySelect
·
2022
·Vol. 7
·期 40
·e202203035
·
IF 2.307
Yuxiu Fu,Yaming Pang,Yinan Zheng,Xiaoli Song,Liguo Gao
Graphical Photocatalysts enhance the ability to absorb low-energy photons due to the reduction of the band gap. Through the photocatalytic mechanism, it is known that when there is irradiation with light (hv) energy entering Mg 2+ -Mo 6+ -Al 3+ -MoO 4 2− -Layered double hydroxides (LDHs), highly active hole-electron pairs will be generated, and a large amount of ⋅OH will be generated after the reaction, which can completely oxidize the phenol in water into CO 2 and H 2 O. Mg 2+ -Mo 6+ -Al 3+ -MoO 4 2− -Layered double hydroxides (LDHs) materials were successfully prepared via a hydrothermal method by doping Mo 6+ in hydroxide laminates and inserting MoO 4 2− to replace the interlayer anions of LDHs materials. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), Fourier transform infrared spectrometer (FTIRS) and ultraviolet-visible spectrophotometer (UV). The electronic density of states was calculated using the density functional theory (DFT) of Vienna Ab-initio Simulation Package (VASP). The effects of Mo 6+ and MoO 4 2− on the structure, morphology, electronic structure and photocatalytic performance of Mg 2+ -Al 3+ -LDHs were systematically studied. The conditions for phenol degradation by Mg 2+ -Mo 6+ -Al 3+ -MoO 4 2− -LDHs were optimized by single factor analysis and response surface methodology. The results show that the MoO 4 2− anion reduces the band gap width and thus enhances the absorption of low-energy photons. The interaction between cations and anions enhances the photocatalytic performance. When the dosage of Mg 2+ -Mo 6+ -Al 3+ -MoO 4 2− -LDHs was 0.03 g, the temperature was 40 °C and the visible light irradiation was 15 min, the removal rate of phenol reached 94.76 %.
研究领域:
环境科学
·
材料科学
✓ 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）