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1.
Org Lett ; 26(11): 2338-2342, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38458971

RESUMEN

A mild, facile, and metal-free approach via the N-heterocyclic carbene-catalyzed SNAr reaction between aryl aldehydes with perfluoroarenes to obtain the coveted functional perfluorinated diarylmethanones is disclosed. This method accommodates a diverse substrate range and exhibits notable tolerance toward various functional groups. Our success in modifying biologically relevant molecules, crafting a fully fluorinated bioisosteric analogue of drug candidate D1, and highlighting the potential of these ketones as valuable electrolyte additives for lithium-ion batteries (LIBs) underscores the versatility of our methodology.

2.
Molecules ; 27(19)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36234775

RESUMEN

In this study, we synthesized three hybrid microporous polymers through Heck couplings of octavinylsilsesquioxane (OVS) with 2,5-bis(4-bromophenyl)-1,3,4-oxadiazole (OXD-Br2), tetrabromothiophene (Th-Br4), and 2,5-bis(4-bromophenyl)-3,4-diphenylthiophene (TPTh-Br2), obtaining the porous organic-inorganic polymers (POIPs) POSS-OXD, POSS-Th, and POSS-TPTh, respectively. Fourier transform infrared spectroscopy and solid state 13C and 29Si NMR spectroscopy confirmed their chemical structures. Thermogravimetric analysis revealed that, among these three systems, the POSS-Th POIP possessed the highest thermal stability (T5: 586 °C; T10: 785 °C; char yield: 90 wt%), presumably because of a strongly crosslinked network formed between its OVS and Th moieties. Furthermore, the specific capacity of the POSS-TPTh POIP (354 F g-1) at 0.5 A g-1 was higher than those of the POSS-Th (213 F g-1) and POSS-OXD (119 F g-1) POIPs. We attribute the superior electrochemical properties of the POSS-TPTh POIP to its high surface area and the presence of electron-rich phenyl groups within its structure.

3.
Micromachines (Basel) ; 13(9)2022 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-36144089

RESUMEN

In this study, we have used the one-pot polycondensation method to prepare novel 2D conjugated microporous polymers (Th-F-CMP) containing thiophene (Th) and fluorene (Fl) moieties through the Suzuki cross-coupling reaction. The thermogravimetric analysis (TGA) data revealed that Th-F-CMP (Td10 = 418 °C, char yield: 53 wt%). Based on BET analyses, the Th-F-CMP sample displayed a BET specific surface area of 30 m2 g-1, and the pore size was 2.61 nm. Next, to show the effectiveness of our study, we utilized Th-F-CMP as a fluorescence probe for the selective detection of Fe3+ ions at neutral pH with a linear range from 2.0 to 25.0 nM (R2 = 0.9349). Furthermore, the electrochemical experimental studies showed that the Th-F-CMP framework had a superior specific capacity of 84.7 F g-1 at a current density of 0.5 A g-1 and outstanding capacitance retention (88%) over 2000 cycles.

4.
Int J Mol Sci ; 23(6)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35328595

RESUMEN

Conductive and porous nitrogen-rich materials have great potential as supercapacitor electrode materials. The exceptional efficiency of such compounds, however, is dependent on their larger surface area and the level of nitrogen doping. To address these issues, we synthesized a porous covalent triazine framework (An-CTFs) based on 9,10-dicyanoanthracene (An-CN) units through an ionothermal reaction in the presence of different molar ratios of molten zinc chloride (ZnCl2) at 400 and 500 °C, yielding An-CTF-10-400, An-CTF-20-400, An-CTF-10-500, and An-CTF-20-500 microporous materials. According to N2 adsorption-desorption analyses (BET), these An-CTFs produced exceptionally high specific surface areas ranging from 406-751 m2·g-1. Furthermore, An-CTF-10-500 had a capacitance of 589 F·g-1, remarkable cycle stability up to 5000 cycles, up to 95% capacity retention, and strong CO2 adsorption capacity up to 5.65 mmol·g-1 at 273 K. As a result, our An-CTFs are a good alternative for both electrochemical energy storage and CO2 uptake.


Asunto(s)
Estructuras Metalorgánicas , Triazinas , Adsorción , Antracenos , Dióxido de Carbono/química , Nitrógeno/química , Triazinas/química
5.
ACS Macro Lett ; 10(1): 110-115, 2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35548989

RESUMEN

Two thermoplastic triblock copolymers of poly(ε-caprolactone)-based acidic (PCL-A) and basic (PCL-B) polymers are synthesized by atom transfer radical polymerization. PCL-A and PCL-B are sequentially electrospun on a sulfur electrode and then ionically cross-linked by an acid-base reaction via hot pressing at 70 °C, which is confirmed by infrared (IR) spectroscopy. The cross-linked PCL-A/PCL-B-electrospun sulfur electrode is assembled as a lithium-sulfur battery with an asymmetric gel polymer electrolyte. The cross-linked polymer is swollen by a liquid electrolyte to form an asymmetric gel polymer electrolyte. The cyclic voltammetry results indicate that the asymmetric gel polymer electrolyte can suppress the dissolution of lithium polysulfides (Li2Sn) into the electrolyte. Furthermore, the lithium-sulfur battery with the asymmetric gel polymer electrolyte exhibits enhanced cycle-life performance.

6.
ACS Omega ; 5(46): 29678-29687, 2020 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-33251403

RESUMEN

We herein report the functionalization of plant oil with norbornene (NB) and subsequent polymerization to prepare biobased thermoset films and biobased binders for silicon/mesocarbon microbead (MCMB) composite electrodes for use in lithium-ion batteries. A series of NB-functionalized plant oils were prepared as biobased thermoset films via ring-opening metathesis polymerization (ROMP) in the presence of a second-generation Grubbs catalyst with tunable thermomechanical properties. Increasing the catalyst loading and cross-linking agent increased cross-link density, storage modulus (E'), and glass transition temperature (T g), while the numbers of unreacted or oligomeric components in the films were reduced. High number of NB rings per triglyceride in the plant oil encouraged monomer incorporation to form a polymer network, therefore accounting for the high T g and E' values. Furthermore, the NB-functionalized plant oil and 2,5-norbornadiene (NBD) were copolymerized as bioderived binders for silicone/MCMB composite electrodes of lithium-ion batteries via ROMP during electrode preparation. Cell performance investigation showed that the silicone/MCMB composite electrode bearing the NBD-cross-linked NB-functionalized plant oil binder exhibited a higher C-rate and cycle-life performance than that using a conventional poly(vinylidene fluoride) (PVDF) binder. Finally, the electrode based on the bioderived binder exhibited a high specific charge capacity of 620 mA h g-1 at 0.5 C.

7.
Macromol Rapid Commun ; 33(2): 107-13, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22134984

RESUMEN

The synthesis and electrochemical performance of three-dimensionally ordered macroporous (3DOM) nitroxide polymer brush electrodes for organic radical batteries are reported. The 3DOM electrodes are synthesized via polystyrene colloidal crystal templating with electropolymerization of polypyrrole, modification of surface initiator, and surface-initiated atom transfer radical polymerization. The discharge capacity of the 3DOM electrodes is proportional to the thickness of the inverse opal. The discharge capacity of the 3DOM electrode at a discharge rate of 5 C is 40 times higher than that of the planar electrode; its cycle-life performance exhibits 96.1% retention after 250 cycles.


Asunto(s)
Polímeros/química , Poliestirenos/química , Pirroles/química , Electroquímica/métodos , Electrodos , Porosidad
8.
Chem Commun (Camb) ; 47(4): 1249-51, 2011 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-21103524

RESUMEN

Nitroxide polymer brushes were covalently patterned on flexible conducting substrates via surface-initiated atom transfer radical polymerization and microcontact printing. As a cathode of organic radical batteries, the nitroxide polymer brushes prevent the nitroxide polymer from dissolving into electrolyte solvents, which improves the cycle-life performance of batteries.

9.
J Am Chem Soc ; 131(32): 11294-5, 2009 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-19637870

RESUMEN

We demonstrate a facile method for fabricating novel 3D microfluidic channels by using two-photon-activated chemistry to locally switch the interior surface of a porous host from a hydrophobic state to a hydrophilic state. The 3D structures can be infilled selectively with water and/or hydrophobic oil with a minimum feature size of only a few micrometers. We envision that this approach may enable the fabrication of complex microfluidic structures that cannot be easily formed via current technologies.


Asunto(s)
Técnicas Analíticas Microfluídicas/instrumentación , Microtecnología/métodos , Fotoquímica/métodos , Polímeros/química , Diseño de Equipo , Interacciones Hidrofóbicas e Hidrofílicas , Porosidad , Dióxido de Silicio/química , Propiedades de Superficie
10.
J Colloid Interface Sci ; 329(2): 300-5, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18977001

RESUMEN

Highly hydroxylated barium titanate (BaTiO(3)) nanoparticles have been prepared via an easy and gentle approach which oxidizes BaTiO(3) nanoparticles using an aqueous solution of hydrogen peroxide (H(2)O(2)). The hydroxylated BaTiO(3) surface reacts with sodium oleate (SOA) to form oleophilic layers that greatly enhance the dispersion of BaTiO(3) nanoparticles in organic solvents such as tetrahydrofuran, toluene, and n-octane. The results of Fourier transform infrared spectroscopy confirmed that the major functional groups on the surface of H(2)O(2)-treated BaTiO(3) nanoparticles are hydroxyl groups which are chemically active, favoring chemical bonding with SOA. The results of transmission electron microscopy of SOA-modified BaTiO(3) nanoparticles suggested that the oleate molecules were bonded to the surfaces of nanoparticles and formed a homogeneous layer having a thickness of about 2 nm. Furthermore, the improved dispersion capability of the modified BaTiO(3) nanoparticles in organic solvents was verified through analytic results of its settling and rheological behaviors.

11.
J Phys Chem B ; 109(49): 23279-84, 2005 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-16375294

RESUMEN

Manganese oxide electrodes composed of interconnected nanowires are electrochemically synthesized in manganous acetate solution at room temperature without any template and catalyst. Annealing temperature affects the electrode morphology, crystallization, and electrochemical performance. Scanning electron microscope (SEM) results show that nanowires are uniformly distributed and sizes are about 12-18 nm in diameter; the diameter decreases to about 8-12 nm after annealing at 300 degrees C. X-ray diffraction (XRD) and transmission electron microscope (TEM) images indicate that nanowires have poor crystalline characteristics. The higher the annealing temperature, the higher the crystalline degree is in manganese oxide. The synthesized anode material shows a much larger capacity than the traditional graphite materials for lithium storage. After annealing at 300 degrees C, the electrode's reversible capacity reaches 800 mAhg(-1), and the specific capacity retention remains nearly constant after 100 cycles.

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