Electrochemical micro analytical device interfaced with portable potentiostat for rapid detection of chlorpyrifos using acetylcholinesterase conjugated metal organic framework using Internet of things

Seeking for low-cost and high-performance electrocatalysts for oxygen evolution reaction (OER) has drawn enormous research interest in the last few years. Reported herein is the topotactic construction of a binuclear...

Download Full-text

Water Photo-Electrooxidation Using Mats of TiO2 Nanorods, Surface Sensitized by a Metal–Organic Framework of Nickel and 1,2-Benzene Dicarboxylic Acid

Hydrogen ◽

10.3390/hydrogen2010004 ◽

2021 ◽

Vol 2 (1) ◽

pp. 58-75

Author(s):

Sheng-Mu You ◽

Waleed M. A. El Rouby ◽

Loïc Assaud ◽

Ruey-An Doong ◽

Pierre Millet

Keyword(s):

Dicarboxylic Acid ◽

Electrochemical Impedance ◽

Metal Organic Framework ◽

Linear Sweep Voltammetry ◽

Tio2 Nanorods ◽

Tem Analysis ◽

Vis Spectroscopy ◽

Metal Organic ◽

Benzene Dicarboxylic Acid ◽

Organic Framework

Photoanodes comprising a transparent glass substrate coated with a thin conductive film of fluorine-doped tin oxide (FTO) and a thin layer of a photoactive phase have been fabricated and tested with regard to the photo-electro-oxidation of water into molecular oxygen. The photoactive layer was made of a mat of TiO2 nanorods (TDNRs) of micrometric thickness. Individual nanorods were successfully photosensitized with nanoparticles of a metal–organic framework (MOF) of nickel and 1,2-benzene dicarboxylic acid (BDCA). Detailed microstructural information was obtained from SEM and TEM analysis. The chemical composition of the active layer was determined by XRD, XPS and FTIR analysis. Optical properties were determined by UV–Vis spectroscopy. The water photooxidation activity was evaluated by linear sweep voltammetry and the robustness was assessed by chrono-amperometry. The OER (oxygen evolution reaction) photo-activity of these photoelectrodes was found to be directly related to the amount of MOF deposited on the TiO2 nanorods, and was therefore maximized by adjusting the MOF content. The microscopic reaction mechanism which controls the photoactivity of these photoelectrodes was analyzed by photo-electrochemical impedance spectroscopy. Microscopic rate parameters are reported. These results contribute to the development and characterization of MOF-sensitized OER photoanodes.

Download Full-text

Construction of Silver Quantum Dot Immobilized Zn-MOF-8 Composite for Electrochemical Sensing of 2,4-Dinitrotoluene

Applied Sciences ◽

10.3390/app9224952 ◽

2019 ◽

Vol 9 (22) ◽

pp. 4952 ◽

Cited By ~ 1

Author(s):

Sushma Rani ◽

Bharti Sharma ◽

Shivani Kapoor ◽

Rajesh Malhotra ◽

Rajender S. Varma ◽

...

Keyword(s):

Quantum Dot ◽

Limit Of Detection ◽

Metal Organic Framework ◽

Linear Sweep Voltammetry ◽

Electrochemical Sensing ◽

Amperometric Determination ◽

Transmission Electron ◽

Electro Catalysis ◽

Metal Organic ◽

Organic Framework

In the present study, we report a highly effective electrochemical sensor for detecting 2,4-dinitrotoluene (2,4-DNT). The amperometric determination of 2,4-DNT was carried out using a gold electrode modified with zinc–metal organic framework-8 and silver quantum dot (Zn-MOF-8@AgQDs) composite. The synthesized nanomaterials were characterized by using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). The synthesized nanocomposite proved to be efficient in electro-catalysis thereby reducing the 2,4-DNT. The unique combination present in Zn-MOF-8@AgQDs composite offered an excellent conductivity and large surface area enabling the fabrication of a highly sensitive (−0.238 µA µM−1 cm−2), selective, rapid and stable 2,4-DNT sensor. The dynamic linear range and limit of detection (LOD) was about 0.0002 µM to 0.9 µM and 0.041 µM, respectively. A 2,4-DNT reduction was also observed during the linear sweep voltammetry (LSV) experiments with reduction peaks at −0.49 V and −0.68 V. This is an unprecedented report with metal organic framework (MOF) composite for sensing 2,4-DNT. In addition, the presence of other species such as thiourea, urea, ammonia, glucose, and ascorbic acid displayed no interference in the modified electrode suggesting its practicability in various environmental applications.

Download Full-text

Application of a Zn(ii) based metal–organic framework as an efficient solid-phase extraction sorbent for preconcentration of plasticizer compounds

RSC Advances ◽

10.1039/c6ra06560k ◽

2016 ◽

Vol 6 (46) ◽

pp. 40211-40218 ◽

Cited By ~ 25

Author(s):

Elham Tahmasebi ◽

Mohammad Yaser Masoomi ◽

Yadollah Yamini ◽

Ali Morsali

Keyword(s):

Solid Phase Extraction ◽

Solid Phase ◽

Low Cost ◽

Metal Organic Framework ◽

Phase Extraction ◽

Metal Organic ◽

Organic Framework

A solid-phase extraction (SPE) sorbent, a Zn(ii) based metal–organic framework, was prepared via a simple, solventless, green and a low-cost mechanosynthesis process.

Download Full-text

Polymer-Assisted Modification of Metal-Organic Framework MIL-96 (Al): Influence on Particle Size, Crystal Morphology and Perfluorooctanoic Acid (PFOA) Removal

10.26434/chemrxiv.12262010 ◽

2020 ◽

Author(s):

Luqman Hakim Mohd Azmi ◽

Daryl R. Williams ◽

Bradley P. Ladewig

Keyword(s):

Particle Size ◽

Crystal Morphology ◽

Low Cost ◽

Metal Organic Framework ◽

Synthesis Method ◽

Perfluorooctanoic Acid ◽

Water Soluble ◽

Water Soluble Polymer ◽

Metal Organic ◽

Organic Framework

<div><b>Abstract</b></div><div>A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine functionality present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.<br></div>

Download Full-text

Polymer-Assisted Modification of Metal-Organic Framework MIL-96 (Al): Influence on Particle Size, Crystal Morphology and Perfluorooctanoic Acid (PFOA) Removal

10.26434/chemrxiv.12262010.v1 ◽

2020 ◽

Author(s):

Luqman Hakim Mohd Azmi ◽

Daryl R. Williams ◽

Bradley P. Ladewig

Keyword(s):

Particle Size ◽

Crystal Morphology ◽

Low Cost ◽

Metal Organic Framework ◽

Synthesis Method ◽

Perfluorooctanoic Acid ◽

Water Soluble ◽

Water Soluble Polymer ◽

Metal Organic ◽

Organic Framework

<div><b>Abstract</b></div><div>A new synthesis method was developed to prepare an aluminum-based metal organic framework (MIL-96) with a larger particle size and different crystal habits. A low cost and water-soluble polymer, hydrolyzed polyacrylamide (HPAM), was added in varying quantities into the synthesis reaction to achieve >200% particle size enlargement with controlled crystal morphology. The modified adsorbent, MIL-96-RHPAM2, was systematically characterized by SEM, XRD, FTIR, BET and TGA-MS. Using activated carbon (AC) as a reference adsorbent, the effectiveness of MIL-96-RHPAM2 for perfluorooctanoic acid (PFOA) removal from water was examined. The study confirms stable morphology of hydrated MIL-96-RHPAM2 particles as well as a superior PFOA adsorption capacity (340 mg/g) despite its lower surface area, relative to standard MIL-96. MIL-96-RHPAM2 suffers from slow adsorption kinetics as the modification significantly blocks pore access. The strong adsorption of PFOA by MIL-96-RHPAM2 was associated with the formation of electrostatic bonds between the anionic carboxylate of PFOA and the amine functionality present in the HPAM backbone. Thus, the strongly held PFOA molecules in the pores of MIL-96-RHPAM2 were not easily desorbed even after eluted with a high ionic strength solvent (500 mM NaCl). Nevertheless, this simple HPAM addition strategy can still chart promising pathways to impart judicious control over adsorbent particle size and crystal shapes while the introduction of amine functionality onto the surface chemistry is simultaneously useful for enhanced PFOA removal from contaminated aqueous systems.<br></div>

Download Full-text

Efficient One-Pot Synthesis of a Hexamethylenetetramine-Doped Cu-BDC Metal-Organic Framework with Enhanced CO2 Adsorption

Nanomaterials ◽

10.3390/nano9081063 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1063 ◽

Cited By ~ 4

Author(s):

Aisha Asghar ◽

Naseem Iqbal ◽

Tayyaba Noor ◽

Majid Ali ◽

Timothy L. Easun

Keyword(s):

Co2 Adsorption ◽

Low Cost ◽

Metal Organic Framework ◽

Single Step ◽

Co2 Uptake ◽

One Pot ◽

Amine Functionalized ◽

Metal Organic ◽

Thermogravimetric Studies ◽

Organic Framework

Herein we report a facile, efficient, low cost, and easily scalable route for an amine-functionalized MOF (metal organic framework) synthesis. Cu-BDC⊃HMTA (HMTA = hexamethylenetetramine) has high nitrogen content and improved thermal stability when compared with the previously reported and well-studied parent Cu-BDC MOF (BDC = 1,4-benzenedicarboxylate). Cu-BDC⊃HMTA was obtained via the same synthetic method, but with the addition of HMTA in a single step synthesis. Thermogravimetric studies reveal that Cu-BDC⊃HMTA is more thermally stable than Cu-BDC MOF. Cu-BDC⊃HMTA exhibited a CO2 uptake of 21.2 wt % at 273 K and 1 bar, which compares favorably to other nitrogen-containing MOF materials.

Download Full-text

Waste PET as a Reactant for Lanthanide MOF Synthesis and Application in Sensing of Picric Acid

Polymers ◽

10.3390/polym11122015 ◽

2019 ◽

Vol 11 (12) ◽

pp. 2015 ◽

Cited By ~ 1

Author(s):

Feng Zhang ◽

Shuyi Chen ◽

Shengqiang Nie ◽

Jun Luo ◽

Shaomin Lin ◽

...

Keyword(s):

Terephthalic Acid ◽

Limit Of Detection ◽

Picric Acid ◽

Metal Organic Framework ◽

Pet Bottles ◽

Metal Organic ◽

Lanthanide Metal ◽

Ft Ir ◽

First Time ◽

Organic Framework

In this study, a lanthanide metal organic framework based on the ligand of terephthalic acid derived from waste polyethylene terephthalate (PET) bottles was designed and synthesized. The structure and morphology of the Tb-BDC was investigated by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The Tb-BDC displays a high selectivity and sensitivity towards picric acid (TNP). The luminescence intensities exhibit a linear relation, with a concentration of TNP over the range of 1 × 10−5–1 × 10−4 M, with a limit of detection of 1 × 10−5 M. The sensing mechanism is also discussed. This is the first time that waste PET materials have been used as the starting precursor of terephthalic acid (BDC) for the fabrication of lanthanide MOF (metal organic framework), which is applied in sensing TNP.

Download Full-text

Rosebengal-Loaded Nanoporous Structure Based on Rare Earth Metal-Organic-Framework: Synthesis, Characterization and Photophysical Performance

Crystals ◽

10.3390/cryst10030185 ◽

2020 ◽

Vol 10 (3) ◽

pp. 185

Author(s):

Kai Song ◽

Han Yu ◽

Jingyi Zhang ◽

Yumeng Bai ◽

Yanjun Guan ◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Metal ◽

Limit Of Detection ◽

Metal Organic Framework ◽

Earth Metal ◽

Nanoporous Structure ◽

Quenching Effect ◽

Metal Organic ◽

Emission Quenching ◽

Organic Framework

A rosebengal-modified nanoporous structure was designed and constructed. This composite structure consisted of an organic sensitizer based on rosebengal and a supporting host of rare earth metal-organic-framework (MOF). It was identified by means of its x-ray diffraction (XRD) pattern, Infrared (IR) spectra, thermal stability and photophysical measurements. Its absorption was increased by 2,4,6-trinitrophenol. Its rosebengal emission was proportionally increased. But its rare earth emission was well-preserved, offering ratiometric signals. These two sensing modes exhibited linear response and good selectivity with a limit of detection (LOD) of 1.9 μM. Its sensing nature was confirmed as the combination of increased rosebengal emission and rare earth emission quenching effect triggered electron-deficient molecules. This nanoporous structure was superior to traditional ones owing to its double sensing modes.

Download Full-text