查找使用阿拉丁产品的科研文献

Core-Shell Self-Doped Polyaniline Coated Metal-Organic-Framework (SPAN@UIO-66-NH2) Screen Printed Electrochemical Sensor for Cd2+ Ions

Xiaoyu Zhao,Wenlong Bai,Yujia Yan,Yanfei Wang,Juankun Zhang

Cadmium ions have variable degrees of toxicity on the environment and organisms. An electrochemical sensor based on self-doped polyaniline (SPAN) modified Metal-organic Framework (SPAN@UIO-66-NH2) with high electron mobility was developed. Cyclic voltammetry and electrochemical impedance spectroscopy indicated that doping of SPAN enhanced the electron transfer rate of UIO-66-NH2 in SPAN@UIO-66-NH2. The optimized Cd2+ sensor exhibited good linear response from 0.5 μg L−1 to 100 μg L−1, low detection limit of 0.17 μg L−1 (based on S/N = 3), good stability, and fast response time. It showed decent reliability for detection of trace Cd2+ in natural lake and urine samples.

Immobilization of high temperature-resistant GH3 β-glucosidase on a magnetic particle Fe3O4-SiO2-NH2-Cellu-ZIF8/zeolitic imidazolate framework

Xuejia Shi,Jin Xu,Changning Lu,Zhenzhong Wang,Wei Xiao,Linguo Zhao

The magnetic particle Fe 3 O 4 -SiO 2 -NH 2 -Cellu-ZIF8 (FSNCZ8) was used to immobilize the high-temperature resistant GH3 β-glucosidase (Tpebgl3) from the Thermomotoga petrophila DSM 13995. The Tpebgl3 has great potential in the catalytic conversion of pharmaceutically active components. The magnetic carrier (FSNCZ8) which provided stronger adsorption capacity, magnetic and high-temperature stability than the previously discussed Fe 3 O 4 -NH 2 -Cellu-ZIF8 without tetraethyl silicate coated. The properties of FSNCZ8-Tpebgl3 (FSNCZ8-T) were as follows: The optimal temperature and pH were 90 °C and 5.5, respectively; the highest activity of FSNCZ8-T approached 2672 U/g; Fe 2+ enabled immobilized enzyme to increase its relative activity to 194%. The main characteristics of FSNCZ8-T, including thermal stability, pH stability, and glucose tolerance, were greatly enhanced by adding Fe 2+ , which was also superior to free enzymes; moreover, the residual activity of FSNCZ8-T was 74% of the initial activity at the end of 10 repeated cycles.

Bromomethylated poly(phenylene oxide) (BPPO)-assisted fabrication of UiO-66-NH2/BPPO/polyethersulfone mixed matrix membrane for enhanced gas separation

Mingmin Jia,Yi Feng,Jianhao Qiu,Xiaocheng Lin,Jianfeng Yao

UiO-66-NH 2 nanocrystals were synthesized and embedded into bromomethylated poly(phenylene oxide)/polyethersulfone (BPPO/PES) polymer matrix to form UiO-66-NH 2 /BPPO/PES mixed matrix membranes (MMMs). The crystalline structure, interaction between UiO-66-NH 2 and BPPO, and dispersion of UiO-66-NH 2 were characterized by FTIR, XRD, and SEM. Nanoparticle dispersion was drastically enhanced with the assistance of BPPO, giving an improved adhesion between the polymer and filler particles. Owing to the intrinsic adsorption property of UiO-66-NH 2 and BPPO to CO 2 , the CO 2 permeability was significantly increased. As a result, the UiO-66-NH 2 /BPPO/PES membrane exhibited enhanced gas separation performance, where CO 2 /N 2 and H 2 /N 2 ideal selectivities were increased to 50.2 and 302.4 with a CO 2 permeability of 125.6 Barrer. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46759.

Synthesis and enhanced visible light-induced photocatalytic activity of a hierarchical porous biomorphic N/Zn–TiO2@NH2-MIL-125 photocatalyst

Du Yingying,Zhao Lei,Chen Hui,Huang Zhaohui,He Xuan,Fang Wei,Li Weixin,Zhang Fuqing,Wang Guanghui

Heterojunction is considered as very promising material for various applications in photocatalysis. Herein, an efficient heterojunction photocatalyst N/Zn–TiO 2 @NH 2 -MIL-125 was successfully synthesized for photo-degradation organic oxidation by biological-templated method. The electron–hole pairs can be separated in space more efficiently because of heterojunction structure. Systematical analyses of spectroscopy and microscopy measurements revealed that N/Zn–TiO 2 @NH 2 -MIL-125 heterojunction materials exhibited hierarchical porous structure with high surface area of 366.02 m 2  g −1 and outstanding optical properties. Photocatalytic activity was investigated by degradating of rhodamine B (1000 µM) under visible-light irradiation. The N/Zn–TiO 2 @NH 2 -MIL-125 showed enhanced photocatalytic activity for RhB degradation, which is respectively about 1.81 and 1.97 times higher than that of the pristine N/Zn–TiO 2 and NH 2 -MIL-125. Various advanced spectroscopic characterizations were applied including photoluminescence, Mott–Schottky curves and electrochemical impedance spectroscopy. A possible mechanism of enhanced photocatalytic oxidation activity for N/Zn–TiO 2 @NH 2 -MIL-125 composite under visible light irradiation was discussed.

A Gel Polymer Electrolyte Based on IL@NH2-MIL-53 (Al) for High-Performance All-Solid-State Lithium Metal Batteries

Sijia Wang,Ye Liu,Liang He,Yu Sun,Qing Huang,Shoudong Xu,Xiangyun Qiu,Tao Wei

Solid polymer composite electrolytes possess the benefits of superior compatibility with electrodes and good thermal characteristics for more secure energy storage equipment. Herein, a new gel polymer electrolyte (GPE) containing NH 2 -MIL-53(Al), [PP 13 ][TFSI], LiTFSI, and PVDF-HFP was prepared using a simple method of solution casting. The effects of encapsulating different ratios of ionic liquid ([PP 13 ][TFSI]) into the micropores of functionalized metal-organic frameworks (NH 2 -MIL-53(Al)) on the electrochemical properties were compared. XRD, SEM, Nitrogen adsorption-desorption isotherms and electrochemical measurements were conducted. This GPE demonstrates a superior ionic conductivity of 8.08×10 –4 S cm –1 at 60 °C and can sustain a discharge specific capacity of 156.6 mAh g –1 at 0.2 C for over 100 cycles. This work might offer a potential approach to alleviate the solid-solid contact with the solid-state electrolyte and electrodes, and broadens up new window for the creation of all-solid-state batteries.

Bioenzyme-free dual-mode sensing for organophosphorus pesticides based on UiO-66-NH2 MOFs encapsulated tris(2,2′-bipyridyl) ruthenium(II)

Gangbing Zhu,Diyan Liao,Nian Hu,Jing Li,Yong He,Yinhui Yi

Herein, we proposed a novel bioenzyme-free dual-mode sensing strategy for the rapid and accurate monitoring of organophosphorus pesticides (OPs) by preparing tris(2,2′-bipyridyl) ruthenium(II) (Ru(bpy) 3 2+ ) encapsulated with UiO-66-NH 2 MOFs as nanozyme (Ru@Zr-MOFs). The as-prepared Ru@Zr-MOFs nanozyme not only exhibits superior peroxidase-like activity which can catalyze O-phenylenediamine (OPD) oxidation to generate yellow 2,3-diaminophenazinc, but also exhibits dual-fluorescence feature (at 442 and 612 nm respectively) and specific interaction capacity with OPs. However, in the existence of OPs, the peroxidase-like activity of Ru@Zr-MOFs nanozyme is restricted and the oxidation process of OPD is stopped; meanwhile, the fluorescence of Ru@Zr-MOFs at 442 nm increases rapidly (< 10 s) while that at 612 nm is apathetic, thus a colorimetric and ratiometric fluorescent sensing strategy was first designed to detect OPs by using glyphosate (Gly) as a typical model of OPs. Then, in consideration of the benefits of smartphone which can make the sensing process more convenient, stable, rapid and sensitive feedback, a smartphone coupled with hydrogel detection platform was proposed also for OPs determination. In addition, the designed sensing strategy offers superior selectivity , stability and real application capabilities. It’s thus expected the as-designed Ru@Zr-MOFs nanozyme based dual-mode sensing strategy possesses important real application for the low-cost, rapid, sensitive and accurate determination of OPs.

Constructing S-scheme heterojunctions with tunable interfacial oxygen vacancy via UiO-66-NH2-derived ZrO2-x for efficient photocatalytic performance

Yu Zhang,Pei Wang,Gaiying Han,Zhaoyang Wang,Haitao Yu,Zhenzi Li,Xuepeng Wang,Ying Xie,Wei Zhou

Defects engineering is significant for photocatalytic environment remediation. To this end, visible-light-driven α-Fe 2 O 3 /ZrO 2-x S-scheme heterojunction photocatalysts with optimal oxygen vacancy (O v ) defects are successfully synthesized via a two-step method. Compared with pristine UiO-66-NH 2 -derived ZrO 2-x and α-Fe 2 O 3 , the heterojunction photocatalysts exhibit a wider range of visible light response and higher efficiency in separating photogenerated electron–hole pairs. Among them, the 5% α-Fe 2 O 3 /ZrO 2-x sample shows the best photocatalytic performance to the degradation of tetracycline (TC) (89.3%), in which the pseudo-first-order kinetic rate constants are 8.20 and 16.75 times that of pristine ZrO 2-x and α-Fe 2 O 3 , respectively. The outstanding photocatalytic degradation efficiency can be attributed to both the narrow-bandgap ZrO 2-x with visible light response and the formation of α-Fe 2 O 3 /ZrO 2-x S-scheme heterojunctions. During the formation of heterojunctions, the concentration of oxygen vacancies (O v ) at the interface of α-Fe 2 O 3 /ZrO 2-x decreases monotonically with the increasing loading of α-Fe 2 O 3 , thereby altering the electronic structure of the photocatalyst and forming the heterojunction firmly. In addition, the high stability implies the potential applications in fields of environment.

Constructing SiAPP-NH2@MOFs Core-Shell Structure Toward Hierarchical Composites With Excellent Flame Retardancy, Smoke Suppression, and Electromagnetic Interference Shielding

Yongqian Shi,Junqiang Han,Ansheng Yao,Miao Liu,Bibo Wang,Cancan Zhang,Hongfei Zou

Designing multifunctional composites with high flame retardancy and excellent electromagnetic shielding performance is of significant importance. In order to address the poor flame retardant and electromagnetic shielding performances of thermoplastic polyurethane (TPU) composites, in this work, the γ-propyl-trimethoxysilane (KH550) functionalized silicon microencapsulated ammonium polyphosphate (SiAPP-NH 2 ) was synthesized using interface modulation technology. Then, SiAPP-NH 2 was combined with a copper metal–organic framework (MOF-Cu) through microencapsulation and electrostatic self-assembly techniques to prepare microencapsulated flame retardants (SiAPP-NH 2 @MOF-Cu). Subsequently, TPU composites were prepared through melt blending of SiAPP-NH 2 @MOF-Cu with TPU material. The results showed that the interface interaction between SiAPP-NH 2 @MOF-Cu and the TPU matrix was significantly enhanced. Compared to pure TPU, TPU/5SAN@1MC composite exhibited decreases of 78.7%, 51.3%, 59.3%, and 58.7% in peak heat release rate, total heat release, total smoke release, and total carbon dioxide release, respectively. In addition, TPU/1SAN@1MC/rGO composite achieved an average shielding effectiveness of 13.82 dB in the X-band, enabling its broad commercial application. This study offers a promising strategy for the fabrication of TPU composites with good flame retardant and electromagnetic shielding properties.

Construction of a sensitive electrochemical biosensor for detecting protein kinase A activity based on NH2-Zr-MOF@Thi signal amplification

Xue Men,Rong Li,Aiwen Su,Yanli Zhang,Lian-Xun Gao,Chengxin Wu,Hongbin Wang,Wenrong Yang,Pengfei Pang

Protein kinase A (PKA) plays a significant role in the regulation of biological activities by the phosphorylation of the specific proteins or substrate peptides. The highly sensitive and reusable electrochemical biosensor has been developed to detect PKA activity based on the specific coordination between Zr 4+ and phosphate group. In this strategy, the specially designed substrate peptide can be anchored on the surface of gold electrode by Au-S bond. In the presence of adenosine triphosphate (ATP) and PKA, the substrate peptide is phosphorylated. Due to the large surface area of MOF and rich Zr 4+ active sites, signal molecule Thionine (Thi) can be absorbed into the cavity of NH 2 -Zr-MOF by the electrostatic interaction to form NH 2 -Zr-MOF@Thi signal probe. The phosphorylated peptide is linked to NH 2 -Zr-MOF@Thi probe because of the strong coordination interaction between Zr 4+ and phosphate group. Therefore, the number of Thi close to the electrode surface is increased and the response signal experiences amplification, markedly enhancing the sensitivity of the detection of PKA activity, which provides an excellent electrochemical sensing platform for PKA activity detection. The response signal of the electrochemical biosensor is proportional to the logarithm of PKA concentration, ranging from 0.05 U mL −1 to 100 U mL −1 , and the limit of detection of this biosensor for PKA is 0.017 U mL −1 when the signal-to-noise ratio is 3. In particular, the proposed method can selectively distinguish the target from other interferents, and can be used to screen potential small molecule inhibitors and detect PKA activity in complex cell samples. Therefore, the developed electrochemical biosensor can be used as a new way for the determination of PKA activity and the screening of its inhibitors in the future.

A chemiluminescence metalloimmunoassay for sensitive detection of alpha-fetoprotein in human serum using Fe-MIL-88B-NH2 as a label

Jingrong Zhou,Zhou Long,Yunfei Tian,Xiaodong Ding,Lan Wu,Xiandeng Hou

A Novel Electrochemiluminescence Sensor for Sensitive Determination of Carbaryl Based on Solid Phase Microextraction at NH2–Graphene–Nafion Modified Electrode

Sui Wang,Shasha Lv,Wenwen Wu,Zhiyong Guo

Sensitive electrochemiluminescence (ECL) detection and solid phase microextraction (SPME) using a NH2–graphene–Nafion modified glassy carbon electrode was developed for carbaryl. The NH2–graphene was synthesised and characterised by Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. The main parameters that affect the extraction efficiencies, such as the buffer and sample pH, and extraction time were investigated and optimised. The introduction of NH2–graphene into Nafion improves the conductivity of the film because of its electrical conductivity. The electrode enables the determination of carbaryl in the range from 5 × 10–4 to 10 μg mL–1, and the limit of detection was 2 × 10–4 μg mL–1 at a signal-to-noise ratio of 3. The ECL intensity retained 97 % of its initial response current after storage for 10 days, indicating a good storage stability of the sensor. The relative standard deviations (RSDs) of intra-assay and inter-assay were found to be 3.5 and 5.3 %, respectively, indicating an acceptable reproducibility. Furthermore, the ECL sensor was successfully applied to the selective and sensitive quantitative determination of carbaryl in river samples, the recoveries of carbaryl ranged from 99.0 to 108.0 %, and the RSDs were less than 5.0 %, which shows good reproducibility and high precision of analysis.

Enhancing corrosion resistance and self-healing of water-borne epoxy coatings using Ti3C2Tx-supported tannic acid on UIO-66-NH2

Xiaoyu Mao,Changhua Li,Xiaofeng Zhang,Hao Chen,Chao Zhang,Rui Gou,Yi He

In this study, we developed a composite material comprising UIO-66-NH 2 encapsulated tannic acid (TA) loaded on Ti 3 C 2 Tx to improve the corrosion resistance of water borne epoxy (WEP) coatings. The successful synthesis of the material was determined by FT-IR, XRD, XPS, EDS, TGA, SEM and TEM characterization. Furthermore, ultraviolet (UV)tests were conducted to evaluate the release rate of TA at varying pH levels, revealing a release rate of approximately 95 % at pH 2. Electrochemical impedance spectroscopy (EIS) results over 60 d indicated that the R c value of TU-T/WEP remained unchanged at 3.934 × 10 8 , demonstrating a two-order magnitude increase compared to those of pure epoxy coatings, attributed to the synergistic active and passive protection of TU-T materials. The self-healing ability of the TU-T/WEP coating was validated through manual scratch experiments. Additionally, the EIS test showed that the R c value of TU-T/WEP coating increased to 3.5 × 10 5 after 72 h, representing a two-order magnitude increase over that of the WEP coating alone. This study introduces a novel approach using green tannic acid as a corrosion inhibitor and amino-functionalized Ti 3 C 2 Tx with UIO-66-NH 2 to enhance corrosion resistance and self-healing aproperties of coatings.