查找使用阿拉丁产品的科研文献

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 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.

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

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.

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.

Experimental and Computational Insights into the Effects of -NH2 and -Cl Functional Groups on the Copper Corrosion Inhibition by Benzotriazole

Thanh Hai Pham,Viorel Chihaia,Phung K. Le,Do Ngoc Son

The influences of -NH2 and -Cl groups on the copper corrosion inhibition in 0.5 M H2SO4 solution by benzotriazole were studied using experimental methods and density functional theory calculations. Mass loss tests, potentiodynamic polarization, and surface morphology analyses revealed notable differences: while unmodified benzotriazole showed an inhibition efficiency of 76.6%, the -Cl derivative increased this to 87.6%, whereas the -NH2 derivative dropped it to 61.0% at the concentration of 5 × 10−4 M. Density functional theory calculations indicated these differences are not due to electronic properties or inhibitor-copper interaction energies but rather to the inhibitor's influence on the oxygen reduction reaction, especially O2 and H2O adsorption. The -NH2 group formed strong hydrogen bonds with O2 and H2O, reducing oxygen reduction inhibition, while the -Cl group repelled O2, resulting in enhanced inhibition. Free energy analysis of the oxygen reduction reaction supported these findings. These new insights into benzotriazole derivatives' copper corrosion inhibition mechanisms offer valuable guidance for developing next-generation corrosion inhibitors.

Flame-retardant effects of NH2-MIL-53(Al) in combination with phosphorus-containing and nitrogen-containing flame retardants on polypropylene

Liang Yu,Lv Shen,Hongzhe Zhong,Ru Zhou,Min Hao,Juncheng Jiang

Polypropylene (PP) flammability poses great fire risks for its application. A metal-organic framework (MOF), NH 2 -MIL-53(Al), was synthesized and subsequently integrated into PP, the flame-retardant efficacy in conjunction with piperazine pyrophosphate (PAPP) and melamine cyanurate (MCA) was additionally examined. When the total mass fraction of the additives was 25 %, the limiting oxygen index (LOI) of PP composite reached 31.1 %, it also passed the UL-94 test with a V-0 rating. The peak heat release rate (pHRR) and the total heat release rate (THR) was reduced by 88.55 % and 79.75 %, respectively, compared with the pure PP. The char residual char percentage increased to 8.02 %. The Tensile Strength reached 30.1 MPa. The results indicate that adding NH 2 -MIL-53(Al) significantly enhanced the flame retardancy and thermal stability of PP composites, without significantly affecting their mechanical properties, which offers a novel potential direction for the advancement of polymer flame retardants (FRs).

Grafting of acidic ionic liquids onto the NH2-UiO-66 for butyric acid glyceride synthesis through heterogeneous catalysis of esterification

Jiawei Zheng,Xiaoyi Zhang,Zhuowa Li,Nanjing Zhong

Immobilization of acid ionic liquid (AIL) for heterogeneous catalysis is benificial for products separation and recycling the AIL for continuing reuse. In this study, AIL was grafted onto the amino group functionalized zirconium-based metal organic framework (NH 2 -UiO-66) to catalyze esterification for short chain fatty acid glycerides synthesis. AIL of 1-(4-Sulfobutyl)-3-Methylimidazolium Hydrogen Sulfate ([HSO 3 -BMIM][HSO 4 ]) was found suitable for short chain fatty acid glycerides after screening varied fatty acids with chain length from 4 to 18. [HSO 3 -BMIM][HSO 4 ] was therefore grafted and butyric acid glyceride was synthesized. Reaction conditions were optimized by means of single factor study and orthogonal experiment. The reusability of the AIL@NH 2 -UiO-66 was evaluated. The AIL@NH 2 -UiO-66 showed good esterificaiton performance and fine reusability. Butyric acid conversion (converted into the glycerides of mono-, di- and tributyrin) at 62.16% was obtained under the optimum conditions. In addition, the present AIL@NH 2 -UiO-66 was quite stable, and 67.39% of its initial esterification activity was retained after 11 cycles of reuse, suggesting it was potential in the esterification reaction.

High-efficiency CO2-epoxide cycloaddition using multifunctional ionic liquids grafted onto UiO-66-NH2 under solvent /cocatalyst both-free conditions

Yuanyuan Cui,Jianmin Sun

Developing a highly efficient catalyst for the conversion of CO 2 into cyclic carbonate is crucial for achieving carbon neutrality. Incorporating target-specific active sites into solid catalysts represents a novel and promising strategy for enhancing the chemical conversion of CO 2 . In this study, the original UiO-66-NH 2 was post-synthetically modified by replacing the H atom of –NH 2 functional group in UiO-66-NH 2 with the Br group in 1-bromobutylimidazole (BIm) under alkaline conditions. Subsequently, the imidazole group in UiO-66-NH 2 -BIm was quaternized with bromoalkyls (including 3-bromopropionic acid, 2-bromoethanol, and 2-bromoethylamine hydrobromide), resulting in the synthesis of UiO-66-NH 2 modified by ionic liquids (ILs) containing hydrogen bond donors, denoted as IL-R@UiO-66-NH 2 (where R OH, NH 2 , COOH). The catalytic performance was assessed in the absence of cocatalyst and solvent at 100 °C, 5 h and 1.0 MPa CO 2 . Notably, IL-COOH@UiO-66-NH 2 exhibited the highest catalytic performance, achieving propylene carbonate yield of 96.1 %. This outstanding performance was attributed to the synergistic interactions between the Lewis acidity of the MOF node, the strong nucleophilicity provided by the Br − of the IL, and the hydrogen bonding interaction facilitated by the carboxyl group, Lewis basic N site from the IL cation. Additionally, IL-COOH@UiO-66-NH 2 demonstrated compatibility with a wide range of epoxy substrates and exhibited good recyclability.

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.

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.

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.