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Covalent triazine framework with efficient photocatalytic activity in aqueous and solid media

Cyrine Ayed, Wei Huang, Kai A. I. Zhang

《化学科学与工程前沿(英文)》 2020年 第14卷 第3期   页码 397-404 doi: 10.1007/s11705-019-1884-2

摘要: Covalent triazine frameworks (CTFs) have been recently employed for visible light-driven photocatalysis due to their unique optical and electronic properties. However, the usually highly hydrophobic nature of CTFs, which originates from their overall aromatic backbone, leads to limitations of CTFs for applications in aqueous media. In this study, we aim to extend the range of the application media of CTFs and design hybrid material of a CTF and mesoporous silica (SBA-15) for efficient photocatalysis in aqueous medium. A thiophene-containing CTF was directly synthesized in mesopores of SBA-15. Due to the high surface area and the added hydrophilic properties by silica, the hybrid material demonstrated excellent adsorption of organic molecules in water. This leads not only to high photocatalytic performance of the hybrid material for the degradation of organic dyes in water, but also for efficient photocatalysis in solvent-free and solid state. Furthermore, the reusability, stability and easy recovery of the hybrid material offers promising metal-free heterogeneous photocatalyst for broader applications in different reaction media.

关键词: photocatalysis     covalent triazine framework     aqueous medium     SBA-15     solid state    

Floret-like Fe–N nanoparticle-embedded porous carbon superstructures from a Fe-covalent triazine polymer

《化学科学与工程前沿(英文)》 2023年 第17卷 第5期   页码 525-535 doi: 10.1007/s11705-022-2232-5

摘要: Fe–Nx nanoparticles-embedded porous carbons with a desirable superstructure have attracted immense attention as promising catalysts for electrochemical oxygen reduction reaction. Herein, we employed Fe-coordinated covalent triazine polymer for the fabrication of Fe–Nx nanoparticle-embedded porous carbon nanoflorets (Fe/N@CNFs) employing a hypersaline-confinement-conversion strategy. Presence of tailored N types within the covalent triazine polymer interwork in high proportions contributes to the generation of Fe/N coordination and subsequent Fe–Nx nanoparticles. Owing to the utilization of NaCl crystals, the resultant Fe/N@CNF-800 which was generated by pyrolysis at 800 °C showed nanoflower structure and large specific surface area, which remarkably suppressed the agglomeration of high catalytic active sites. As expect, the Fe/N@CNF-800 exhibited unexpected oxygen reduction reaction catalytic performance with an ultrahigh half-wave potential (0.89 V vs. reversible hydrogen electrode), a dominant 4e transfer approach and great cycle stability (> 92% after 100000 s). As a demonstration, the Fe/N-PCNF-800-assembled zinc–air battery delivered a high open circuit voltage of 1.51 V, a maximum peak power density of 164 mW·cm–2, as well as eminent rate performance, surpassing those of commercial Pt/C. This contribution offers a valuable avenue to exploit efficient metal nanoparticles-based carbon catalysts towards energy-related electrocatalytic reactions and beyond.

关键词: Fe–Nx nanoparticles     hypersaline-confinement conversion     floret-like carbon     covalent triazine polymers     oxygen reduction reaction    

Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen

《化学科学与工程前沿(英文)》 2021年 第15卷 第6期   页码 1550-1560 doi: 10.1007/s11705-021-2104-4

摘要: The low cost and highly efficient construction of electrocatalysts has attracted significant attention owing to the use of clean and sustainable energy technologies. In this work, cobalt nanoparticle decorated N-doped carbons (Co@NC) are synthesized by the pyrolysis of a cobalt covalent organic framework under an inert atmosphere. The Co@NC demonstrates improved electrocatalytic capabilities compared to N-doped carbon without the addition of Co nanoparticles, indicating the important role of cobalt. The well-dispersed active sites (Co-Nx) and the synergistic effect between the carbon matrix and Co nanoparticles greatly enhance the electrocatalytic activity for the oxygen reduction reaction. In addition, the Co content has a significant effect on the catalytic activity. The resulting Co@NC-0.86 exhibits a superb electrocatalytic activity for the oxygen reduction reaction in an alkaline electrolyte in terms of the onset potential (0.90 V), half-wave potential (0.80 V) and the limiting current density (4.84 mA·cm–2), and a high selectivity, as well as a strong methanol tolerance and superior durability, these results are comparable to those of the Pt/C catalyst. Furthermore, the superior bifunctional activity of Co@NC-0.86 was also confirmed in a home-built Zn-air battery, signifying the possibility for application in electrode materials and in current energy conversion and storage devices.

关键词: cobalt embedment     N-doped carbons     covalent organic framework     oxygen reduction     Zn-air battery    

Co anchored on porphyrinic triazine-based frameworks with excellent biocompatibility for conversion of

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1761-1771 doi: 10.1007/s11705-022-2195-6

摘要: Microbial electrosynthesis is a promising alternative to directly convert CO2 into long-chain compounds by coupling inorganic electrocatalysis with biosynthetic systems. However, problems arose that the conventional electrocatalysts for hydrogen evolution may produce extensive by-products of reactive oxygen species and cause severe metal leaching, both of which induce strong toxicity toward microorganisms. Moreover, poor stability of electrocatalysts cannot be qualified for long-term operation. These problems may result in poor biocompatibility between electrocatalysts and microorganisms. To solve the bottleneck problem, Co anchored on porphyrinic triazine-based frameworks was synthesized as the electrocatalyst for hydrogen evolution and further coupled with Cupriavidus necator H16. It showed high selectivity for a four-electron pathway of oxygen reduction reaction and low production of reactive oxygen species, owing to the synergistic effect of Co–Nx modulating the charge distribution and adsorption energy of intermediates. Additionally, low metal leaching and excellent stability were observed, which may be attributed to low content of Co and the stabilizing effect of metalloporphyrins. Hence, the electrocatalyst exhibited excellent biocompatibility. Finally, the microbial electrosynthesis system equipped with the electrocatalyst successfully converted CO2 to poly-β-hydroxybutyrate. This work drew up a novel strategy for enhancing the biocompatibility of electrocatalysts in microbial electrosynthesis system.

关键词: microbial electrosynthesis     hydrogen evolution reaction     metalloporphyrins     biocompatibility     CO2 conversion    

Room temperature preparation of hydrazine-linked covalent organic frameworks coated capillaries for

《化学科学与工程前沿(英文)》 2023年 第17卷 第5期   页码 548-556 doi: 10.1007/s11705-022-2252-1

摘要: Covalent organic frameworks (COFs) have been increasingly used in capillary electrochromatography due to their excellent characteristics. In this work, hydrazine-linked TFPB-DHzDS (TFPB: 1,3,5-tris(4-formylphenyl)benzene; DHzDS: 2,5-bis(3-(ethylthio)propoxy)terephthalohydrazide) was first synthesized by a simpler and easier method at room temperature and introduced into capillary electrochromatography as coating material. The TFPB-DHzDS coated capillaries were prepared by an in-situ growth process at room temperature. After optimizing the coating concentration and experimental conditions of capillary electrochromatography, baseline separation of two groups of polycyclic aromatic hydrocarbons was achieved based on the TFPB-DHzDS coated capillary. And the established method was used successfully to determine PAHs in natural water and soil samples. The spiked recoveries of polycyclic aromatic hydrocarbons in these samples ranged from 90.01% to 111.0%, indicating that the method is reliable and could detect polycyclic aromatic hydrocarbons in natural samples. Finally, molecular simulation was applied to study and visualize the interaction between the analytes and coating COF materials to investigate the molecular level separation mechanism further.

关键词: hydrazine-linked TFPB-DHzDS     in-situ growth method     open-tubular capillary electrochromatography     molecular simulations    

Trihydrazinotriazine-grafting Fe

Jamal Rahimi, Seyedeh Shadi Mirmohammadi, Ali Maleki

《化学科学与工程前沿(英文)》 2021年 第15卷 第4期   页码 1008-1020 doi: 10.1007/s11705-020-1996-8

摘要: This study focuses on the synthesis and characterization of a novel magnetic nanocomposite 2,4,6-trihydrazino-1,3,5-triazine (THDT)-functionalized with silica-coated iron oxide magnetic nanoparticles (MNPs). This nanocomposite has porous morphology decorated with the spherical MNPs. Through co-precipitation of iron salts, MNPs were obtained. The prepared THDT was placed on the chlorine surface-modified MNPs. The present environment-friendly nanocatalyst intensely accelerated the synthesis of highly functionalized tetrahydrobenzo[ ]pyran derivatives as well as reduced the reaction times and increased yields of the products.

关键词: trihydrazino-triazine     porous     magnetic nanocatalyst     green chemistry     tetrahydrobenzo[b]pyrans    

Metal-organic framework UiO-66 membranes

Xinlei Liu

《化学科学与工程前沿(英文)》 2020年 第14卷 第2期   页码 216-232 doi: 10.1007/s11705-019-1857-5

摘要: Metal-organic frameworks (MOFs) have emerged as a class of promising membrane materials. UiO-66 is a prototypical and stable MOF material with a number of analogues. In this article, we review five approaches for fabricating UiO-66 polycrystalline membranes including synthesis, secondary synthesis, biphase synthesis, gas-phase deposition and electrochemical deposition, as well as their applications in gas separation, pervaporation, nanofiltration and ion separation. On this basis, we propose possible methods for scalable synthesis of UiO-66 membranes and their potential separation applications in the future.

关键词: membrane     metal-organic framework     UiO-66     separation    

Iteration framework for solving mixed lubrication computation problems

《机械工程前沿(英文)》 2021年 第16卷 第3期   页码 635-648 doi: 10.1007/s11465-021-0632-8

摘要: The general discrete scheme of time-varying Reynolds equation loses the information of the previous step, which makes it unreasonable. A discretization formula of the Reynolds equation, which is based on the Crank–Nicolson method, is proposed considering the physical message of the previous step. Gauss–Seidel relaxation and distribution relaxation are adopted for the linear operators of pressure during the numerical solution procedure. In addition to the convergent criteria of pressure distribution and load, an estimation framework is developed to investigate the relative error of the most important term in the Reynolds equation. Smooth surface with full contacts and mixed elastohydrodynamic lubrication is tested for validation. The asperity contact and sinusoidal wavy surface are examined by the proposed discrete scheme. Results show the precipitous decline in the boundary of the contact area. The relative error suggests that the pressure distribution is reliable and reflects the accuracy and effectiveness of the developed method.

关键词: mixed lubrication     discretization formula     relative error     Reynolds equation     asperity    

Optimizing iodine capture performance by metal–organic framework containing with bipyridine units

《化学科学与工程前沿(英文)》 2023年 第17卷 第4期   页码 395-403 doi: 10.1007/s11705-022-2218-3

摘要: Radioactive iodine exhibits medical values in radiology, but its excessive emissions can cause environmental pollution. Thus, the capture of radioiodine poses significant engineering for the environment and medical radiology. The adsorptive capture of radioactive iodine by metal–organic frameworks (MOFs) has risen to prominence. In this work, a Th-based MOF (denoted as Th-BPYDC) was structurally designed and synthesized, consisting of [Th63-O)43-OH)4(H2O)6]12+ clusters, abundant bipyridine units, and large cavities that allowed guest molecules diffusion and transmission. Th-BPYDC exhibited the uptake capacities of 2.23 g·g−1 and 312.18 mg·g−1 towards I2 vapor and I2 dissolved in cyclohexane, respectively, surpassing its corresponding analogue Th-UiO-67. The bipyridine units boosted the adsorption performance, and Th-BPYDC showed good reusability with high stability. Our work thus opened a new way for the synthesis of MOFs to capture radioactive iodine.

关键词: metal–organic framework     iodine     adsorption     nuclear waste     environmental remediation    

Fluorescence detection of phosphate in an aqueous environment by an aluminum-based metal-organic framework

《环境科学与工程前沿(英文)》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1594-8

摘要:

● A novel Al-MOF was successfully synthesized by a facile solvothermal method.

关键词: Fluorescence     Metal-organic framework     Phosphate     Detection     Al-MOF    

MANURE AND METROPOLES---A GLOBAL FRAMEWORK FOR NUTRIENT CYCLING IN FOOD SYSTEMS

《农业科学与工程前沿(英文)》 2021年 第8卷 第1期

Nickel-based metal−organic framework-derived whisker-shaped nickel phyllosilicate toward efficiently

《化学科学与工程前沿(英文)》 2022年 第16卷 第10期   页码 1493-1504 doi: 10.1007/s11705-022-2168-9

摘要: Metal−organic framework-derived materials have attracted significant attention in the applications of functional materials. In this work, the rod-like nickel-based metal−organic frameworks were first synthesized and subsequently employed as the hard templates and nickel sources to prepare the whisker-shaped nickel phyllosilicate using a facile hydrothermal technology. Then, the nickel phyllosilicate whiskers were evaluated to enhance the mechanical, thermal, flammable, and tribological properties of epoxy resin. The results show that adequate nickel phyllosilicate whiskers can disperse well in the matrix, improving the tensile strength and elastic modulus by 13.6% and 56.4%, respectively. Although the addition of nickel phyllosilicate whiskers could not obtain any UL-94 ratings, it enhanced the difficulty in burning the resulted epoxy resin nanocomposites and considerably enhanced thermal stabilities. Additionally, it was demonstrated that such nickel phyllosilicate whiskers preferred to improve the wear resistance instead of the antifriction feature. Moreover, the wear rate of epoxy resin nanocomposites was reduced significantly by 80% for pure epoxy resin by adding 1 phr whiskers. The as-prepared nickel phyllosilicate whiskers proved to be promising reinforcements in preparing of high-performance epoxy resin nanocomposites.

关键词: metal−organic framework     nickel phyllosilicate     whisker     epoxy resin     mechanical response     tribological performance     flammable property    

Energy neutrality potential of wastewater treatment plants: A novel evaluation framework integrating

《环境科学与工程前沿(英文)》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1549-0

摘要:

• Framework of indicators was established based on energy efficiency and recovery.

关键词: Wastewater treatment plants     Energy neutrality potential     Energy efficiency     Energy recovery     Evaluation framework    

DNA alkylation promoted by an electron-rich quinone methide intermediate

Chengyun Huang,Steven E. Rokita

《化学科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 213-221 doi: 10.1007/s11705-015-1541-3

摘要: Biological application of conjugates derived from oligonucleotides and quinone methides have previously been limited by the slow exchange of their covalent self-adducts and subsequent alkylation of target nucleic acids. To enhance the rates of these processes, a new quinone methide precursor with an electron donating substituent has been prepared. Additionally, this substituent has been placed to the nascent -methylene group of the quinone methide for maximum effect. A conjugate made from this precursor and a 5'-aminohexyloligonucleotide accelerates formation of its reversible self-adduct and alkylation of its complementary DNA as predicted from prior model studies.

关键词: quione methide     DNA alkylation     reversible covalent reaction     bioconjugation     target-directed modification of nucleic acids    

The effect of altering crosslinker chemistry during interfacial polymerization on the performance of nanofiltration membranes for desalination, organic, and micropollutants removal

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2025-2036 doi: 10.1007/s11705-023-2356-2

摘要: Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical properties. In this study, we designed and fabricated three novel membranes with different active layers using the crosslinkers: terephthaloyl chloride, isophthaloyl chloride, and trimesoyl chloride. The crosslinkers were reacted with an aqueous solution of an aliphatic tetra-amine. Because these crosslinkers differ in their structures and crosslinking mechanisms during interfacial polymerization, the resultant membranes also possess different structural properties. The water contact angle of the fabricated membranes also varies; the water contact angles of 4A-3P-TPC@PSF/PET, 4A-3P-TMC@PSF/PET, and 4A-3P-IPC@PSF/PET, are 68.9°, 65.6°, and 53.9°, respectively. Similarly, the desalination performance of resultant membranes also showed variations, with 4A-3P-TPC@PSF/PET, 4A-3P-IPC@PSF/PET, and 4A-3P-TMC@PSF/PET having a permeate flux of 17.14, 25.70, and 30.90 L·m−2·h−1, respectively, at 2.5 MPa. The 4A-3P-TPC@PSF/PET membrane exhibited extensive crosslinking with aliphatic linear amine, and cationic dye rhodamine B, MgCl2, and amitriptyline rejection rates of 98.6%, 92.7% and 80.9%, respectively. The 4A-3P-TMC@PSF/PET membrane showed mediocre performance, while 4A-3P-IPC@PSF/PET membrane showed even lower performance, with a 35% rejection of methyl orange dye.

关键词: acid chlorides     covalent crosslinking     desalination     linear aliphatic amine     micropollutant removal     thin film composite membranes    

标题 作者 时间 类型 操作

Covalent triazine framework with efficient photocatalytic activity in aqueous and solid media

Cyrine Ayed, Wei Huang, Kai A. I. Zhang

期刊论文

Floret-like Fe–N nanoparticle-embedded porous carbon superstructures from a Fe-covalent triazine polymer

期刊论文

Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen

期刊论文

Co anchored on porphyrinic triazine-based frameworks with excellent biocompatibility for conversion of

期刊论文

Room temperature preparation of hydrazine-linked covalent organic frameworks coated capillaries for

期刊论文

Trihydrazinotriazine-grafting Fe

Jamal Rahimi, Seyedeh Shadi Mirmohammadi, Ali Maleki

期刊论文

Metal-organic framework UiO-66 membranes

Xinlei Liu

期刊论文

Iteration framework for solving mixed lubrication computation problems

期刊论文

Optimizing iodine capture performance by metal–organic framework containing with bipyridine units

期刊论文

Fluorescence detection of phosphate in an aqueous environment by an aluminum-based metal-organic framework

期刊论文

MANURE AND METROPOLES---A GLOBAL FRAMEWORK FOR NUTRIENT CYCLING IN FOOD SYSTEMS

期刊论文

Nickel-based metal−organic framework-derived whisker-shaped nickel phyllosilicate toward efficiently

期刊论文

Energy neutrality potential of wastewater treatment plants: A novel evaluation framework integrating

期刊论文

DNA alkylation promoted by an electron-rich quinone methide intermediate

Chengyun Huang,Steven E. Rokita

期刊论文

The effect of altering crosslinker chemistry during interfacial polymerization on the performance of nanofiltration membranes for desalination, organic, and micropollutants removal

期刊论文