A CГh 3
CLICK HERE - https://urlin.us/2tlHwd
The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
The synthesis of an NbO-type metal-organic framework was achieved by design: o-Br-BDC (BDC = benzenedicarboxylate) was used to direct the formation of Cu2(CO2)4 paddle wheel units at 90 degrees to each other and thus yield the target network. The compound was formulated as Cu2[o-Br-BDC]2(H2O)2.(DMF)8(H2O)2 (MOF-101) and characterized by single-crystal X-ray diffraction [cubic, space group Imm (No. 229) with a = 21.607(3) A, V = 10088(2) A3, Z = 6], which fully confirmed the presence of the expected structure. Despite having very large apertures and voids, MOF-101 has a noninterpenetrated structure, an intriguing observation that is discussed in the context of dual structures.
During this time the performance of our website may be affected - searches may run slowly and some pages may be temporarily unavailable. If this happens, please try refreshing your web browser or try waiting two to three minutes before trying again. We apologise for any inconvenience caused and thank you for your patience.
If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.
The use of semiconductors for bacterial photoinactivation is a promising approach that has attracted great interest in wastewater remediation. The photoinactivator Cu-TTC/ZTO/TO was synthesized by the solvothermal method from the coordination complex Cu(C3H3N3S3)3 (Cu-TTC) and the hybrid semiconductor ZnTiO3/TiO2 (ZTO/TO). In this study, the effect of photocatalyst composition/concentration as well as radiation intensity on the photoinactivation of the gram-negative bacteria Escherichia coli and the gram-positive bacteria Staphylococcus aureus in aqueous solutions was investigated. The results revealed that 25 mg/mL of photoinactivator, in a Cu-TTC:ZTO/TO molar ratio of 1:2 (w/w%) presents a higher rate of bacterial photoinactivation under simulated solar light (λ = 300-800 nm) in comparison to the individual components. The evidence of this study suggests that the presence of the Cu(C3H3N3S3)3 coordination complex in the ZnTiO3/TiO2 hybrid semiconductor would contribute to the generation of reactive oxygen species (ROS) that are essential to initiate the bacterial photoinactivation process. Finally, the results obtained allow us to predict that the Cu-TTC/ZTO/TO photocatalyst could be used for effective bacterial inactivation of E. coli and S. aureus in aqueous systems under simulated solar light.
This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.
Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.
The findings of this study are available within the paper and its Supplementary Information. Crystallographic parameters for compounds 14 and 62 are available free of charge from the Cambridge Crystallographic Data Centre under CCDC 1923926 (14) and 1923927 (62). All data are available from the authors upon reasonable request.
C.-J.Y., C.Z. and Q.-S.G. designed the experiments and analysed the data. C.-J.Y., C.Z., J.-H.F., X.-L.S., L.Y., Y.S., Y.T. and Z.-L.L. performed the experiments. All authors participated in writing the manuscript. X.-Y.L. conceived and supervised the project.
Metal organic frameworks (MOF) are a new materials with many remarkable advantages such as being porous, having a low density, high adsorption ability and high specific surface area, leading to many applications in gas storage, gas separation, gas purification, catalysis, supercapacitors, and electrode materials for batteries [1], [2], [3], [4], [5], [6], [7]. There are hundreds of types of MOF which have been synthesized by many different methods such as the mechanochemical method, solvothermal method, microwave method, chemical method and electrochemical method [1], [6], [8], [9], [10], [11], [12], [13], [14]. Cu-BTC, which is formed from Cu and benzene-1,3,5-tricarboxylic acid (H3BTC) is well known and is one of the MOF materials which has been studied by many scientists. We chose to synthesize MOF based on Cu-BTC, by an electrochemical method, since Cu is a common and cheap metal and this method is environmentally friendly, with no use of toxic solvent and a large amount of pure material can be obtained in a short time. Cu-BTC has many applications, namely in gas storage (hydrogen [1], methane, carbon dioxide [15]), gas separation [15], supercapicitors [2], catalysis [4], [5] and sensors [13]. Electrochemical methods, namely with applied current, applied potential or scanning potential processes, can be used to synthesize MOF. The morphology, structure and properties of MOF are affected by many factors in the synthesis process such as the organic ligand, the nature of metal ion, the solvent, temperature, pH, synthesis time, electrolyte and Cu-BTC treatment process such as a hydration process [12], [15]. Some research has shown that synthesized Cu-BTC has a small specific surface area or is unstable in water and that a hydration step can increase the Brunauer, Emmett and Teller (BET) specific surface area. This paper presents results obtained by the investigation of the effects of the electrolyte, the synthesis time, the hydration process and dehydration process on the morphology, structure, specific surface area and stability in water of MOF based on Cu-BTC synthesized by applying a controlled potential.
Cu-BTC material was synthesized by applying a potential of 5 V/saturated calomel reference electrode (SCE) in a three electrode electrochemical cell containing 80 ml of a solution with a composition as follows:
The cell includes an SCE, a working electrode (limited area: 10 cm2) and counter electrode both in Cu 99.61% with 20 mm50 mm3 mm in size. The chemical composition is shown in Table 1. The Cu electrode was mechanically polished by abrasive paper 400, 800, 1200 (Japan), rinsed by distilled water and solvent. The electrochemical experiments were conducted with Autolab equipment (AUT71290, Netherland).
Figure 1 presents the current intensity as a function of time during the synthesis process of Cu-BTC at 5 V/SCE in solution containing methanol+H3BTC 0.05 M+TBATFB 0.05 M (DD2). At the beginning, the current increases quickly due to the formation of copper ions on the electrode surface; after that, the current reaches a stable value at 0.420 A corresponding to the synthesis process of Cu-BTC.
2θ, (hkl), distance between crystal plane d and lattice parameter a of Cu-BTC, formed from Cu and benzene-1,3,5-tricarboxylic acid, synthesized with electrolyte tetrabutylammonium tetrafluoroborate (TBATFB).
Figure 5 presents scanning electron microscopy images of Cu-BTC synthesized at 5 V with TBATFB or NaNO3. Cu-BTC has a nonuniform block shape with size from 50 nm to 900 nm when synthesized in solution containing TBATFB (Figure 5A). In the presence of NaNO3, the obtained Cu-BTC has a plate shape with large sizes from 100 nm to 3 µm (Figure 5B).
Electrodeposition time can affect the morphology and phase structure of Cu-BTC. Long synthesis time is advantageous for the growth of single crystals. Figure 6 presents X-ray diffraction patterns of Cu-BTC synthesized in DD2 during different times. All the characteristic peaks of Cu-BTC 3D structure can be observed (Table 4). This result shows that the electrodeposition time does not affect the phase structure of Cu-BTC 3D.
X-ray diffraction patterns of Cu-BTC, formed from Cu and benzene-1,3,5-tricarboxylic acid, synthesized in DD2 with different times: 10 min (A), 15 min (B), 25 min (C) and 60 min (D) (2-Cu-BTC 3D, 3-C3H5CuO2).
From the X-ray diffraction pattern, the lattice parameter (a) of Cu-BTC with different synthesis times can be calculated (Table 5). When the reaction time increases, the lattice parameter (a) increases slightly and the size of crystal rises.
To study the effect of the reaction time on the formation of Cu-BTC 1D, we electrodeposited Cu-BTC in DD1 with an applied potential of 5 V/SCE during 10 min and 60 min. The X-ray diffraction patterns of Cu-BTC synthesized in DD1 with different times are shown in Figure 7.
X-ray diffraction patterns of Cu-BTC, formed from Cu and benzene-1,3,5-tricarboxylic acid, synthesized in DD1 with an applied potential of 5 V/saturated calomel reference electrode (SCE) during (A) 10 min and (B) 60 min (1-Cu-BTC 1D, 3-C3H5CuO2, 4-C8H4CuO43H20, 5-C6H5Cu, 6-C4H4CuO42H2O). 59ce067264