A Novel of PTA/ZIF-8@Cellulose Aerogel Composite Materials for Efficient Photocatalytic Degradation of Organic Dyes in Water

A novel PTA/ZIF-8@CA composite material (PTA = phosphotungstic acid; CA = cellulose aerogel) with multilayer three-dimensional network structure was synthesized with cellulose aerogel as the framework and MOFs as the filler. The results showed that the degradation rates of methylene blue at δ = 10 ppm reached 99.8 % respectively in 30 min under the conditions of PTA/ZIF-8@CA input amount of 0.6 g · L^–1 and pH = 5. The degradation rate of rhodamine B at δ = 10 ppm reached 99.7 % in 60 min. This shows that PTA/ZIF-8@CA has excellent degradation efficiency and short-term performance. In addition, after 5 photocatalytic cycles, the degradation rates of methylene blue and rhodamine B by PTA/ZIF-8@CA were still 83.0 % and 82.5 %, respectively, reflecting that PTA/ZIF-8@CA has terrific photocatalysis stability.     

Fabrication of the Metal-Organic Framework Membrane with Excellent Adsorption Properties for Paraben Based on Micro Fibrillated Cellulose

A kind of novel environmental-friendly composite absorbent material was designed and prepared in this paper. Nanoscale metal-organic frameworks(MOFs) were embedded in the skeleton of cotton micro fibrillated cellulose. By scanning electron microscope(SEM), we observed that a large number of MOFs were attached to the cellulose skeleton. In addition, under the condition of 1800 r/min vortex, the structure of the composite material was stable and was not easily damaged by external forces. The water contact angle test showed that the composite material had excellent hydrophilicity and could be used for the adsorption of pollutants. Then, the material was characterized by energy dispersive X-ray spectroscopy(EDX), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR) and BET adsorption. Through verification, the material had very stable reusability(n=10). The composite material was applied to the solid phase extraction of water samples, such as rain water, toning water and fruit juice, and was quantitatively analyzed by high performance liquid chromatography(HPLC)-UV. This method was then applied to the extraction of four parabens(methyl-, ethyl-, propyl-, and butyl-paraben) from real samples, yielding limits of detection(LODs) of 0.29-0.58 ng/mL. The linear range was 2-500 ng/mL. The inter-day and intra-day recoveries were 90.7%-106.0% and 87.1%-109.3%, respectively(relative standard deviation<10.8%).     

Nano/Micro HKUST-1 Fabricated by Coordination Modulation Method at Room Temperature

A simple and fast route for the synthesis of metal-organic framework(MOF) particles was presented.Cu 3(BTC) 2(HKUST-1,BTC=1,3,5-benzenetricarboxylate),one of the most well-known MOFs,was synthesized at room temperature via coordination modulation method.By adding different modulators(monocarboxylic acids) into the reaction system,the morphologies of HKUST-1 crystals were tuned from nano spheres to micro octahedrons at room temperature without any complex equipment.X-Ray diffractions and gas sorption measurements revealed highly crystalline particles with large Brunauer-Emmett-Teller(BET) surface areas(1116―1273 m 2 /g) and total pore volumes(0.62―0.73 cm 3 /g).The significantly small particle sizes and high capacity of gas sorption are considered advantageous for envisaged application in practical industrial process.     

Recent Advances of Metal-Organic Frameworks-based Nanozymes for Bio-applications

Artificial nanoenzymes with enzyme-like catalytic activity have gradually become an alternative to natural enzymes due to their low production cost, high stability, and good tolerance. In recent years, various enzyme mimics have emerged with the rapid development of nano-teclnology. Metal-organic frameworks(MOFs) are a novel class of porous inorganic-organic hybrid materials made from metal ions/clusters and organic ligands, and MOFs-based nanozymes show great prospect in biosensing, biocatalysis, biomedical imaging, and therapeutic applications, due to unique properties, such as high specific surface area, high porosity, tunable morphology, and excellent biocatalytic properties. In this paper, the recent progresses concerning MOFs-based nanozymes are systematically summarized, including the synthesis, design strategies and related applications, which are divided into two major categories, namely, MOFs structured nanoenzymes and MOFs composite structured nanoenzymes. Meanwhile, the applications of various classifications of MOFs research are introduced. At the end, current challenges and future perspectives of MOFs-based nanozymes are also discussed. It is highly expected that this review on this important area can provide a meaningful guidance for tumor therapy, biosensing and other aspects.     

金属-有机骨架材料用于去除天然气中H2S的计算研究

众所周知, 天然气作为一种利用效率高的清洁能源, 其需求量正与日俱增. 但天然气中包含的H₂S等有害气体会危害人类健康、腐蚀设备、污染生态环境等. 为解决这一问题, 寻找良好的H₂S吸附剂, 本文采用巨正则系综蒙特卡罗(GCMC)模拟方法, 针对天然气中H₂S/CH₄混合气分离, 对33种具有代表性的稳定金属-有机骨架(MOF)材料进行H₂S选择性和工作容量(变压吸附(PSA)及真空变压吸附(VSA)过程)的筛选. 结果表明,ZIF-80, Zn₂-bpydtc, CAU-1-(OH)₂, CH₃O-MOFa最适用于本体系VSA过程的气体分离; 而后两者最适用于PSA过程的气体分离.通过分析高选择性和高工作容量材料的结构特征, 发现改性官能基团以及小孔作用的出现是影响选择性的关键因素, 其中―Cl、―OH、―OCH₃基团对H₂S气体的吸附作用力最强. 具有高的工作容量材料的特点是选择性高, 对气体吸附作用力大, 吸附位置多. 基于筛选出的高选择性、高工作容量的稳定MOF材料总结出的强化H₂S选择性及工作容量的一般性规律, 为MOF材料应用于天然气脱硫提供了理论基础.     

A Luminescent Metal-Organic Framework with LON Topology for Highly Effective Fluorescence Sensing of Fe3+ and TNP

Aluminescent Ag-based metal-organic framework(1) has been synthesized and its structure has been characterized. Compound 1 was fabricated using the Ag⁺ and bbimb^2‒ ligands and manifestes a rare LON topology. Compound 1 is selective not only in detecting traces of Fe³⁺ and 2,4,6-trinitrophenol(TNP) via luminescence quenching, but also demonstrates high selectivity in the presence of other competitors. Compound 1’s K_sv values towards Fe³⁺ can reach as high as 9.3×10³ L/mol, which is higher than those of several other MOF materials. It is also a recyclable luminous sensor with the potential to be utilized for detecting TNP. Hence, based on its characteristics, compound 1 can be regarded as a prospective luminescence sensor for detecting Fe³⁺ and TNP.     

纳微尺度铜金属有机框架催化过氧化氢氧化异丁香酚

通过水热法及沉淀法,合成了纳微尺度铜金属有机框架催化剂。 通过FT-IR、TG及TEM等技术手段对其性能和结构进行了表征。 系统考察了催化剂、溶剂种类及用量、反应时间等因素对异丁香酚氧化制备香草醛的影响。 结果表明,用均苯三甲酸根(BTC)作配体时制备的催化剂Cu-BTC性能较佳。 以Cu-BTC为催化剂、30%(质量分数)H₂O₂为氧化剂、乙腈为介质,当n(异丁香酚):n(H₂O₂)=1:2.4时,50 ℃,反应8 h,异丁香酚转化率为94.4%,香草醛产率达到81.8%。 纳微尺度(粒径30~300 nm)Cu-BTC催化剂体现了良好的重复使用性能,连续反应5次,异丁香酚转化率保持在90%左右。     

An Overview of Metal-Organic Framework Based Electrocatalysts: Design and Synthesis for Electrochemical Hydrogen Evolution,Oxygen Evolution,and Carbon Dioxide Reduction Reactions

Due to the increasing global energy demands, scarce fossil fuel supplies, and environmental issues, the pursued goals of energy technologies are being sustainable, more efficient, accessible, and produce near zero greenhouse gas emissions. Electrochemical water splitting is considered as a highly viable and eco-friendly energy technology. Further, electrochemical carbon dioxide (CO₂) reduction reaction (CO₂RR) is a cleaner strategy for CO₂ utilization and conversion to stable energy (fuels). One of the critical issues in these cleaner technologies is the development of efficient and economical electrocatalyst. Among various materials, metal-organic frameworks (MOFs) are becoming increasingly popular because of their structural tunability, such as pre- and post- synthetic modifications, flexibility in ligand design and its functional groups, and incorporation of different metal nodes, that allows for the design of suitable MOFs with desired quality required for each process. In this review, the design of MOF was discussed for specific process together with different synthetic methods and their effects on the MOF properties. The MOFs as electrocatalysts were highlighted with their performances from the aspects of hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and electrochemical CO₂RR. Finally, the challenges and opportunities in this field are discussed.     

Ecofriendly and sustainable Sargassum spp.-based system for the removal of highly used drugs during the COVID-19 pandemic

Analgesic consumption increased significantly during the COVID-19 pandemic. A high concentration of this kind of drug is discarded in the urine, reaching the effluents of rivers, lakes, and seas. These medicines have brought serious problems for the flora and, especially, the ecosystems’ fauna. This paper presents the results of removing diclofenac, ibuprofen, and paracetamol in an aqueous solution, using Sargassum spp. from the Caribbean coast. The study consisted of mixing each drug in an aqueous solution with functionalized Sargassum spp in a container under constant agitation. Therefore, this work represents an alternative to solve two of the biggest problems in recent years; first, the reduction of the overpopulation of sargassum through its use for the remediation of the environment. Second is the removal of drug waste used excessively during the COVID-19 pandemic. Liquid samples of the solution were taken at intervals of 10 min and analyzed by fluorescence to determine the concentration of the drug.The sorption capacity for diclofenac, ibuprofen, and paracetamol was 2.46, 2.08, and 1.41 μg/g, corresponding to 98 %, 84 %, and 54 % of removal, respectively. The removal of the three drugs was notably favored by increasing the temperature to 30 and 40 °C, reaching efficiencies close to 100 %. Moreover, the system maintains its effectiveness at various pH values. In addition, the Sargassum used can be reused for up to three cycles without reducing its removal capacity. The wide diversity of organic compounds favors the biosorption of drugs, removing them through various kinetic mechanisms. On the other hand, the Sargassum used in the drugs removal was analyzed by X-ray diffraction, FTIR spectroscopy, TGA analysis, and scanning electron microscopy before and after removal. The results showed an evident modification in the structure and morphology of the algae and demonstrated the presence of the biosorbed drugs. Therefore, this system is sustainable, simple, economical, environmentally friendly, highly efficient, and scalable at a domestic and industrial level that can be used for aquatic remediation environments.     

A 3D Ba-MOF for selective adsorption of CO_2/CH_4 and CO_2/N_2

An unexpected in-situ hydrolysis reaction occurred during the solvothermal reaction of N,N'-bis(4-carboxy-2-methylphenyl)pyromellitic di-imide) and Ba(NO_3)_2,and a novel porous Ba-MOF,[H_2 N(CH_3)_2]_(0.5) [Ba_(1.5)(L)(DMA)]·1.5 DMA·1.5 H_2 O(UPC-70,H3 L=2-(4-ca rboxy-2-methylphenyl)-1,3-dioxoisoindoline-5,6-dicarboxylic acid,DMA=N,N-dimethylacetamide),was obtained on the basis of the partial hydrolysate.The as-synthesized 3 D network with 1 D open channels of different sizes(24 A and 10 A)contains abundant open metal sites after removal of solvents,which is conducive to the preferential adsorption of CO_2.The subsequent gas sorption measurement reveals the high separation selectivity of UPC-70 for CO_2/CH_4(15) and CO_2/N_2(32) at ambient conditions,and GCMC theoretical simulation provides good verification of the experimental results,indicating that UPC-70 is a potential candidate for CO_2 capture from flue gas and natural gas.     

Ionic Liquid-assisted Formation of Lanthanide Metal-organic Framework Nano/Microrods for Superefficient Removal of Congo Red

New lanthanide metal-organic framework(MOF) nano/microrods, [C₄mim]Cl-Eu-MOF, [C₈mim]Cl-Eu- MOF and [C₁₂mim]Cl-Eu-MOF, were conveniently synthesized via an ionic liquid-assisted hydrothermal method and characterized by means of powder X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), thermogravimetric analysis(TG) and transmission electron microscopy(TEM). The obtained nano/microrods with low surface areas were efficient for the removal of Congo red(CR) from aqueous solutions. Under the optimum conditions, [C₄mim]Cl-Eu-MOF with a specific surface area of 5.1 m²/g exhibited an ultrahigh adsorption capacity of 2606 mg/g toward CR. Notably, the adsorption efficiency of [C₄mim]Cl-Eu-MOF for CR via nano/microscale stacking can be directly demonstrated by TEM. In-depth understanding of CR removal by [C₄mim]Cl-Eu-MOF nano/microrods was also supported by FTIR, Raman spectroscopy and zeta potential analyses.     

Fe／ZrO_2气凝胶超细粒子催化剂的制备、表征及F－T反应性能的研究

用超临界流体干燥法制备出大孔高比表面高分散态Ｆｅ／ＺｒＯ_２气凝胶超细粒子催化剂，研究了在其制备过程中织构性质、颗粒大小、体相和表面结构的变化，并与普通浸渍法制备的Ｆｅ／ＺｒＯ_２催化剂作了对比。对几种Ｆｅ／ＺｒＯ_２催化剂的Ｆ－Ｔ反应性能考察表明，Ｆｅ／ＺｅＯ_２气凝胶超细催化剂显示出高的反应活性；随载体ＺｒＯ_２颗粒尺寸减小，活性组分铁的分散度变大，其颗粒尺寸变小，催化剂比表面积增大，反应活性增大，甲烷和低碳烃生成量增加，重质组分减少，认为产物烃分布主要受催化剂活性相颗粒尺寸效应制约。     

基于金属有机框架/卟啉/多壁碳纳米管构建的新型葡萄糖非酶传感器

利用钴卟啉(Co-TCPP)的催化性能、多壁碳纳米管(MWCNTs)的良好导电性和金属有机框架(Co-MOFs)的高密度活性位点,通过温和方法制备了新型复合材料Co-TCPP/MWCNTs@Co-MOFs,并用此材料构筑了一种新型葡萄糖非酶传感器.电化学实验结果表明,该传感器对葡萄糖具有良好的响应.     

聚苯胺纳/微米结构薄膜的制备及对pH传感的影响

考察了溶液酸度对纳/微米结构聚苯胺生长的影响. 在0.1 mol/L硫酸、pH=4和pH=7的磷酸缓冲溶液及0.1 mol/L氨水中, 在冰冻条件下氧化聚合苯胺单体, 在溶液中和浸入反应溶液的玻璃基底上分别得到一系列不同形貌的聚苯胺, 如: 纳米仙人球、微米席子、微米片、微米花、三维网络、微米树状物和微米枝等. 各种形貌的形成机理归结为pH的影响和冰的晶体结构的模板作用. 另外, 浸入反应溶液的基底诱导作用和聚合物扩散受限生长导致基底上树状结构的形成. 基底上原位沉积的薄膜直接用于对pH缓冲溶液的响应研究, pH范围宽(pH=3~9), 反应灵敏.     

A Novel Electrochemical Sensor for Detection of Baicalein in Human Serum Based on DUT‐9/Mesoporous Carbon Composite

DUT‐9/mesoporous carbon (DUT‐9/MC) nanocomposites were synthesized by in‐situ growth of nickel‐based metal‐organic frameworks (DUT‐9) on the MC for the first time. Compared with original DUT‐9 crystals, the presence of MC in the composites can avoid the agglomeration of DUT‐9 sheets, increase the specific surface area and reduce the electron transfer resistance. DUT‐9/MC shows enhanced electrocatalytic activity toward redox of baicalein compared with DTU‐9. The possible electrocatalytic redox mechanism of baicalein involves two electrons and two protons. Under the optimized conditions, the proposed sensor shows a wide linear relationship in the concentration range of 0.05‐20 μM (R²=0.993, sensitivity of 0.1188 μA/μM) with a low detection limit of 0.015 μM. It is worth noting that the oxidation overpotential of baicalein (0.107 V) is significantly lower than that of most literatures in pH 7.0. Meanwhile, the proposed sensor shows satisfactory results for the detection of baicalein in human serum samples. This research provides a highly efficient strategy for fabricating novel electrochemical sensor based two‐dimensional lamellar structure MOFs.     

Post Synthetic Modification of NH2-(Zr-MOF) via Rapid Microwave-promoted Synthesis for Effective Adsorption of Pb(II) and Cd(II)

Excessive heavy metals in the water constitute a health hazard to humans, yet it may be efficiently purified using adsorbents. Herein, for the first time, UiO-66-NH₂ was modified by Glycidyl methacrylate (GMA) via microwave heating method to investigate its potential for adsorption of Pb(II) and Cd(II) metal ions. Synthesized MOF was characterized by TGA, XRD, BET, FE-SEM-EDX, and FTIR. The MOF has a huge surface area of 1144 m²/g, a mean pore diameter of 2.84 nm, and a total pore volume of 0.37 cm³/g. The effect of UiO-66-GMA performance was evaluated by investigating the impact of pH (1–9), contact time (0–200 min), initial metal ions concentration (20–1000 mg/L), temperature (25–55 °C), adsorbent dosage (0.5–3 g/L), and co existences of other metals was investigated on Pb(II) and Cd(II) percentage removal. Following an analysis of the adsorption isotherms, kinetics, and thermodynamics, the Temkin isothermal model showed an excellent fit with the adsorption data (R² = 0.99). The adsorption process was a spontaneous endothermic reaction and kinetically followed the pseudo-second-order kinetics model. Microwave heating method produced highly crystalline small Zr-MOF nanoparticles with a short reaction time. It promoted the simple yet highly efficient synthesis of Zr-based MOFs, as shown by the reaction mass space-time yield. The adsorption capability of Pb to the presence of several polar functional groups, including as primary and secondary amines, ester, alkene, and hydroxyl groups. This adsorbent is a potential candidate for wastewater treatment due to its outstanding structural stability in acidic and basic solutions, high removal efficiency, and recyclability.     

面向乙烷/乙烯分离的金属有机框架膜的大规模计算筛选

相比于传统热驱动的低温蒸馏工艺, 基于金属有机框架(Metal-organic frameworks, MOFs)的膜分离是一种在技术和成本上可行的乙烷/乙烯分离替代方案. 为了加速MOF膜在这一气体分离领域中的应用, 本工作提出了两步筛选策略对12,020个真实MOF膜材料进行了大规模计算筛选, 其中MISQIQ04表现出最高的乙烷/乙烯膜选择系数(4.16)和较高的乙烷渗透率(4.35×10⁵ Barrer). 通过结构-性能关系分析, 可以发现窄孔径和低孔隙率的MOFs是选择性分离乙烷的最佳膜材料, 并且乙烷的选择性吸附对乙烷/乙烯膜分离过程起着主导作用. 与传统计算筛选方法相比, 本工作所提出的筛选策略降低了约87.1%的计算时间成本. 为了进一步缩短模拟时间, 本工作还开发了机器学习分类模型以实现对高性能MOF膜的快速预筛选并探讨了该模型的可移植性. 结果表明, 增加数据集的多样性有助于提高所开发模型的可移植性和泛化能力.     

原位组装在碳纸上的有机金属骨架材料衍生的NC/Co/CoP催化剂用于碱性环境水分解（英文）

随着世界工业经济的发展,作为不可再生能源的化石燃料消耗日趋增大并带来严重的环境污染.氢能具有能量密度高、燃烧无污染等优点,被认为是替换传统化石燃料的理想能源之一.通过电化学方法实现水裂解制氢是既满足环境要求又符合氢气生产需要的一种潜在有效方法,受到人们广泛关注.基于铂、钌等贵金属的电催化剂在水裂解中具有很高的活性,然而其稀缺性和高成本是阻碍其大规模实际应用的重要因素.水裂解制氢包括二电子转移的质子还原和四电子转移的水氧化两个过程.相对于质子还原,水氧化反应动力学过程缓慢,是决定水裂解速率的关键.通常,质子还原反应倾向于在酸性条件下进行,而水氧化反应在碱性环境下更有利,反应条件的差异阻碍了水裂解制氢的发展.因此,制备在碱性环境下具有高催化性能、高稳定性和低成本的催化剂是促进水裂解制氢能源技术进一步发展的关键.金属有机骨架(MOF)衍生的复合催化剂具有良好的催化性能和广阔的应用前景,在催化反应中得到越来越多的重视.传统的催化剂组装方式是通过全氟磺酸聚合物等辅助剂将催化剂组装到工作电极上,这些辅助剂具有较强的酸性,而且会覆盖催化剂表面的催化活性位点,降低催化剂比表面积,阻碍催化剂活性的进一步提升.本文通过电泳的方法,将ZIF-67负载到碳纸上,进一步通过碳化、部分磷化过程得到NC/Co/Co P/CP催化电极.研究发现,在碱性环境(1 mol/LKOH)下,催化电流达到10 m A/cm^2的析氢过电位只有208 m V,析氧反应的过电位为350 m V,在二电极体系中所需的电压也只有1.72 V,催化活性明显高于通过传统方法组装的电极.在长时间的电化学稳定性测试中,经过20h的电流测试和1000次的CV测试后,该电极的催化活性没有明显下降.我们报道了一种基于MOF材料的复合电极组装新方法,为MOF材料在能源储存与转化领域应用提供了新思路.     

有机太阳能电池给受体材料界面的微纳结构调控

有机太阳能电池因具有成本低、质轻、柔韧性好、可大面积印刷制备等优势,引起了人们极大的关注并成为现阶段有机电子学研究的重要热点之一。有机功能层中电子给体和受体界面特性对电池的功率转换效率影响很大,通过给受体界面的微纳结构化,可扩大给受体的接触面积、缩短给体和受体的距离、增强光吸收,能产生更多激子并促进激子有效分离,从而有效提高器件的电池效率。本文综述了纳米压印、自组装、溶剂挥发以及模板法等调控微纳结构的技术和方法,总结了基于微纳结构构建有机光伏器件的发展现状,并对目前微纳结构化方法和光伏应用中存在问题和研究重点做了简要评述,最后展望了该研究领域下一步的发展方向和应用前景。     

A unique 3D microporous MOF constructed by cross-linking 1D coordination polymer chains for effectively selective separation of CO_2/CH_4 and C_2H_2/CH_4

Selective separation of CO_2/CH_4 and C_2 H_2/CH_4 are promising for their high-purity industrial demand and scientific research on account of the similar molecular radius and physical properties.In this work,a unique 3 D microporous MOF material [Cu(SiF_6)(sdi)_2]·solvents(1,sdi=1,1'-sulfonyldiimidazole) was successfully constructed by cross-linking 1 D coordination polymer chains.The dense functional active sites on the inner walls of the channel of la can provide strong binding affinities to CO_2,C_2 H_2,and thus effectively improve the gas separation performance of CO_2/CH_4 and C_2 H_2/CH_4.