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1.
Macromol Rapid Commun ; 45(1): e2300238, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37335809

RESUMO

Engineering of conjugated microporous polymers (CMPs) with high porosity, redox activity, and electronic conductivity is of significant importance for their practical applications in electrochemical energy storage. Aminated-multiwall carbon nanotubes (NH2 -MWNT) are utilized to modulate the porosity and electronic conductivity of polytriphenylamine (PTPA), which is synthesized via Buchwald-Hartwig coupling reaction of tri(4-bromophenyl)amine and phenylenediamine as constitutional units in a one-step in situ polymerization process. Compared to PTPA, the specific surface area of core-shell PTPA@MWNTs has been greatly improved from 32 to 484 m2  g-1 . The PTPA@MWNTs exhibites an improved specific capacitance, with the highest value 410 F g-1 in 0.5 M H2 SO4 at a current of 10 A g-1 achieve for PTPA@MWNT-4 due to the hierarchical meso-micro pores, high redox-activity and electronic conductivity. Symmetric supercapacitor assemble by PTPA@MWNT-4 has a capacitance of 216 F g-1 of total electrode materials and retains 71% of initial capacitance after 6000 cycles. This study gives new insights into the role of CNT templates in the adjustment of molecular structure, porosity, and electronic property of CMPs for the high-performance electrochemical energy storage.


Assuntos
Nanotubos de Carbono , Porosidade , Polímeros/química , Eletrodos , Oxirredução
2.
Angew Chem Int Ed Engl ; 63(23): e202404563, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38565431

RESUMO

Bipyridine-based covalent organic frameworks (COFs) have emerged as promising contenders for the photocatalytic generation of hydrogen peroxide (H2O2). However, the presence of imine nitrogen alters the mode of H2O2 generation from an efficient one-step two-electron (2e-) route to a two-step 2e- oxygen reduction pathway. In this work, we introduce 3,3'-bipyridine units into imine-based COF skeletons, creating a pyridyl-imine structure with two adjacent nitrogen atoms between the pyridine ring and imine linkage. This unique bipyridine-like architecture can effectively suppress the two-step 2e- ORR process at the single imine-nitrogen site, facilitating a more efficient one-step 2e- pathway. Consequently, the optimized pyridyl-imine COF (PyIm-COF) exhibits a remarkable H2O2 production rate of up to 5850 µmol h-1 g-1, nearly double that of pristine bipyridine COFs. This work provides valuable insight into the rational design of functionalized COFs for enhanced H2O2 production in photocatalysis.

3.
Angew Chem Int Ed Engl ; : e202406427, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837308

RESUMO

Tuning the interfacial structure of metal oxide substrates is an essential strategy to induce electronic structure reconstruction of supported catalysts, which is of great importance in optimizing their catalytic activities. Herein, vanadium oxides-supported Ir catalysts (Ir-V2O3, Ir-VO2, and Ir-V2O5) with different interfacial bonding environments (Ir-V, Ir-Obri, and Ir-O, respectively) were investigated for hydrogen evolution reaction (HER). The regulating mechanism of the influence of different interfacial bonding environments on HER activity was investigated by both experimental results and computational evidence. Benefiting from the unique advantages of interfacial Ir-V direct metal bonds in Ir-V2O3, including enhanced electron transfer and electron donation ability, an optimized HER performance can be obtained with lowest overpotentials of 16 and 26 mV at 10 mA cm-2, high mass activities of 11.24 and 6.66 A mg-1, and turnover frequency values of 11.20 and 6.63 s-1, in acidic and alkaline conditions respectively. Furthermore, the assembled Ir-V2O3||RuO2 anion exchange membrane (AEM) electrolyzer requires only 1.92 V to achieve a high current density of 500 mA cm-2 and realizes long-term stability. This study provides essential insights into the regulating mechanism of interfacial chemical bonding in electrocatalysts and offers a new pathway to design noble metal catalysts for different applications.

4.
Environ Sci Technol ; 57(30): 11325-11335, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37395618

RESUMO

Simultaneous recovery of energy and carbon from recalcitrant wastewater has attracted ever-growing interest for water management. However, the existing technologies to break down recalcitrant pollutants are mainly energy and chemical intensive. Here, a novel hydrothermal reaction amended with activated carbon (AC) was demonstrated to enable an unprecedented 99.5% removal of an exemplar difficult-to-degrade contaminant, polyvinyl alcohol (PVA), from wastewater. Meanwhile, an easy-separated hydrochar (C6H7.08O0.99) with an abundance of unsaturated aromatic rings was produced, exhibiting 118.46% of energy yield with a high heating value of 32.9 MJ/kg, outperforming the hydrochar(s) reported to date. The retrieved energy from the hydrochar was able to entirely offset the energy needs for this hydrothermal process. Interestingly, the AC catalyst can sustain in situ reuse over 125 cycles with no evidence of irreversible deactivation. The adjacent carbonyl groups on AC were revealed to provide active sites for dehydrogenation from either the C-H (1.24 Å) or O-H (1.40 Å) bond in PVA, forming hydroxyl groups on AC and highly reactive intermediates (ΔG0 = -11.5 kcal/mol). It was further proved that the free oxygen in the headspace extracted H atoms from the newly formed hydroxyl groups on AC (ΔG0 = -4.7 kcal/mol), thus regenerating the carbonyl sites on AC for the next catalytic hydrothermal dehydrogenation cycles. The long-lasting catalyst reusability and energy self-sufficient approach offer a sustainable route to carbon neutrality in recalcitrant wastewater treatment.

5.
Macromol Rapid Commun ; 44(20): e2300309, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37501566

RESUMO

With the rapid development of energy storage technology, the operation of portable and wearable devices is inseparable from high energy density power supplies. However, the demand for high performance supercapacitors in movable smart electronics is still restrained by their insufficient areal capacitance and limited power/energy densities. In addition, some electroactive materials, including metal oxides, conductive polymers, graphene, porous carbons, etc., are inevitable to use extra adhesives for the preparation of electrode materials. In this work, integrated hierarchical graphitic porous carbon membranes used as the electrodes without adhesives are successfully synthesized, via pyrolyzing poly(ionic liquid)s (PILs)-metal organic frameworks (MOFs) composite membranes. The asymmetric supercapacitor is assembled by the carbonized PIL-MOF composite membrane and PILs-derived porous carbon membrane, and exhibits significant areal capacitance with remarkable power and energy densities. In the two-electrode system, the areal capacitance can reach 9.5 F cm-2 with an energy density of 1.91 mWh cm-2 . In the fabricated all-solid-state supercapacitors, the areal capacitance and energy density achieved 3.2 F cm-2 and 0.65 mWh cm-2 , respectively, exceeding most reported ones. Therefore, the integrated carbon membrane electrodes with high areal capacitance reveal great potential in miniaturized devices, and further show a wider application scope through regulating PILs.


Assuntos
Grafite , Líquidos Iônicos , Estruturas Metalorgânicas , Nanoporos , Carbono
6.
Macromol Rapid Commun ; 41(22): e2000489, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33051928

RESUMO

Capturing volatile radioactive nuclides including iodine (I129 or I131 ) is one of the major problems to be solved for environmental sustainability. Multiple types of functional microporous materials such as metal organic frameworks and covalent organic frameworks have been constructed for iodine emission control. However, most of the microporous materials are limited by their weak binding force with iodine and low stability, leading to low capture efficiencies. Herein, the synthesis of pyridyl conjugated microporous polymer networks with large surface areas (PCMP-Y) up to 1304 m2 g-1 and high yields up to 95% via a simple Yamamoto cross-coupling reaction, is reported. The PCMP-Y carries amine and pyridine N groups which have stronger interactions with iodine molecules. The high specific surface areas and porosities of PCMP-Y facilitate iodine capture, delivering a maximum adsorption capacity of 4.75 g g-1 in a short time (3 h), which is superior to a majority of porous materials reported. Moreover, the reversible desorption nature of PCMP-Y capturing iodine imparts a platform for metal-free heterogeneous catalyst, which can be applied to synthesize aminobenzothiazole medicines via O2 -promoted cascade reactions.


Assuntos
Iodo , Polímeros , Adsorção , Catálise , Porosidade
7.
Macromol Rapid Commun ; 40(24): e1900455, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31709638

RESUMO

Nitrogen-rich conjugated microporous polymers (CMPs) with tunable porosities and reversible redox properties have received increasing interest as electrode materials for supercapacitors. Herein, pyridyl building blocks with different substitutions are selected to synthesize four amine-linked conjugated microporous polytriphenylamine (PTPA) networks via Buchwald-Hartwig cross-coupling reaction engineering the redox activity of PTPAs. The structures, porosities, and redox activities of these four PTPAs are investigated. The electrochemical characterization results show that PTPA obtained using 2,5-diaminopyridine dihydrochloride (i.e., PTPA-25) displays the highest specific capacitances up to 335 F g-1 in 1.0 m H2 SO4 at a current density of 0.5 A g-1 . Upon 5000 cycles, PTPA-25 maintains good initial capacitances up to 65%, nearly 100% Coulombic efficiencies at a current density of 2 A g-1 , and high rate properties (remained a high capacitance of 250 F g-1 at 10 A g-1 ). The influence of different substitutions of pyridyl on the redox activities of the synthesized PTPA electrodes is further proposed, which would give insight into engineering the performance of CMPs-based supercapacitors.


Assuntos
Compostos de Anilina/química , Polímeros/química , Compostos de Anilina/síntese química , Técnicas Eletroquímicas , Eletrodos , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Estrutura Molecular , Oxirredução , Tamanho da Partícula , Polímeros/síntese química , Porosidade , Propriedades de Superfície
8.
Small ; 14(42): e1803232, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30230234

RESUMO

Cobalt nanocrystals encapsulated in N,O-dual-doped porous carbons as efficient and stable electrocatalysts for hydrogen evolution reaction (HER) are reported. A heteroatom-rich-conjugated microporous polymer is first chemically deposited on a carbon fiber cloth, and after addition of a cobalt salt, pyrolyzed to produce a heteroatom-doped C/Co nanocrystal composite. With this process, the use of additional binders for preparation of electrodes can be avoided. With a trace cobalt loading (0.46 wt%), the electrodes achieve a low Tafel slope of 46 mV dec-1 and overpotential of only 69 mV at a current density of 10 mA cm-2 in 0.5 m H2 SO4 . Experimental and computational studies reveal that the superior HER behavior is due to a decreased free energy of hydrogen adsorption, induced by i) electrons transferred from the cobalt nanocrystals to graphite layers and ii) N,O-dual doping reduced the Fermi level of neighboring C atoms.

9.
Macromol Rapid Commun ; 35(21): 1833-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25228586

RESUMO

Novel macrocyclic amine-linked oligocarbazole hollow microspheres are synthesized via a one-step oxidative method in aqueous solution. Upon altering the oxidants and acidic media, the average diameters of the obtained hollow microspheres are tunable from 0.23 to 2.0 µm. With attractive amine and carbazole functionalities, exposed surface area, thermostability, and photoluminescent properties, the amine-linked oligocarbazole hollow microspheres are directly assembled to yield heavy metal sorbents with excellent selectivity and recyclability, shown to efficiently remove lead from contaminated water.


Assuntos
Aminas/química , Carbazóis/química , Compostos Macrocíclicos/química , Microesferas , Adsorção , Técnicas de Química Sintética/métodos , Dimerização , Condutividade Elétrica , Fluorescência , Chumbo/química , Chumbo/isolamento & purificação , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Modelos Químicos , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
10.
Int J Mol Sci ; 15(1): 774-86, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24406731

RESUMO

This study reports a new type of drug-loaded core-shell nanofibers capable of providing dual controlled release with tunable dose in the second phase. The core-shell nanofibers were fabricated through a modified coaxial electrospinning using a Teflon-coated concentric spinneret. Poly(vinyl pyrrolidone) and ethyl cellulose were used as the shell and core polymer matrices respectively, and the content of active ingredient acetaminophen (APAP) in the core was programmed. The Teflon-coated concentric spinneret may facilitate the efficacious and stable preparation of core-shell nanofibers through the modified coaxial electrospinning, where the core fluids were electrospinnable and the shell fluid had no electrospinnability. The resultant nanofibers had linear morphologies and clear core-shell structures, as observed by the scanning and transmission electron microscopic images. APAP was amorphously distributed in the shell and core polymer matrices due to the favorite second-order interactions, as indicated by the X-ray diffraction and FTIR spectroscopic tests. The results from the in vitro dissolution tests demonstrated that the core-shell nanofibers were able to furnish the desired dual drug controlled-release profiles with a tunable drug release amount in the second phase. The modified coaxial electrospinning is a useful tool to generate nanostructures with a tailored components and compositions in their different parts, and thus to realize the desired functional performances.


Assuntos
Acetaminofen/metabolismo , Portadores de Fármacos/química , Nanofibras/química , Acetaminofen/química , Celulose/análogos & derivados , Celulose/química , Povidona/química , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Small Methods ; : e2301554, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485672

RESUMO

Solar energy is a primary form of renewable energy, and photothermal conversion is a direct conversion process with tunable conversion efficiency. Among various kinds of photothermal conversion materials, porous organic polymers (POP) are widely investigated owing to their controllable molecular design, tailored porous structures, good absorption of solar light, and low thermal conductivity. A variety of POP, such as conjugated microporous polymers (CMP), covalent organic frameworks (COF), hyper-crosslinked porous polymers (HCP), polymers of intrinsic microporosity (PIM), porous ionic polymers (PIP), are developed and applied in photothermal conversion applications of seawater desalination, latent energy storage, and biomedical fields. In this review, a comprehensive overview of the recent advances in POP for photothermal conversion is provided. The micro molecular structure characteristics and macro morphology of POP are designed for applications such as seawater desalination, latent heat energy storage, phototherapy and photodynamic therapy, and drug delivery. Besides, a probe into the underlying mechanism of structural design for constructing POP with excellent photothermal conversion performance is methodicalized. Finally, the remaining challenges and prospective opportunities for the future development of POP for solar energy-driven photothermal conversion applications are elucidated.

12.
Adv Sci (Weinh) ; : e2401966, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828756

RESUMO

Engineering a catalytic membrane capable of efficiently removing emerging organic microcontaminants under ultrahigh flux conditions is of significance for water purification. Herein, drawing inspiration from the functional attributes of lymphatic vessels involved in immunosurveillance and fluid transport with minimal energy consumption, a novel hierarchical porous catalytic membrane is engineered. This membrane, based on an innovative nitrogen-rich conjugated microporous polymer (polytripheneamine, PTPA), is synthesized using an electrospinning coupled in situ polymerization approach. The resulting bioinspired membrane with hierarchical channels comprises a thin layer (≈1.7 µm) of crosslinked PTPA nanoparticles covering the interconnected electrospun nanofibers. This unique design creates an intrinsic microporous angstrom-confined system capable of activating peroxymonosulfate (PMS) to generate 98.7% singlet oxygen (1O2), enabling durable and highly efficient degradation of microcontaminants. Additionally, the presence of a thin layer of mesoporous structure between PTPA nanoparticles and macroporous channels within the interwoven nanofibers enhances mass transfer efficiency and facilitates high flux rates. Notably, the prepared hierarchical porous organic catalytic membrane demonstrates enduring high-efficiency degradation performance with a superior permeance (>95% and >2500 L m-2 h-1 bar-1) sustained over 100 h. This work introduces an innovative pathway for the design of high-performance catalytic membranes for the removal of emerging organic microcontaminants.

13.
Adv Mater ; 36(16): e2305755, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38227620

RESUMO

Gradients play a pivotal role in membrane technologies, e.g., osmotic energy conversion, desalination, biomimetic actuation, selective separation, and more. In these applications, the compositional gradients are of great relevance for successful function implementation, ranging from solvent separation to smart devices; However, the construction of functional gradient in membranes is still challenging both in scale and directions. Inspired by the specific function-related, graded porous structures in glomerular filtration membranes, a general approach for constructing gradient covalent organic framework membranes (GCOMx) applying poly (ionic liquid)s (PILs) as template is reported here. With graded distribution of highly porous covalent organic framework (COF) crystals along the membrane, GCOMx exhibts an unprecedented asymmetric solvent transport when applying different membrane sides as the solvent feed surface during filtration, leading to a much-enhanced flux (10-18 times) of the "large-to-small" pore flow comparing to the reverse direction, verified by hydromechanical theoretical calculations. Upon systematic experiments, GCOMx achieves superior permeance in nonpolar (hexane ≈260.45 LMH bar-1) and polar (methanol ≈175.93 LMH bar-1) solvents, together with narrow molecular weight cut-off (MWCO, 472 g mol-1) and molecular weight retention onset (MWRO, <182 g mol-1). Interestingly, GCOMx shows significant filtration performance in simulated kidney dialysis, revealing great potential of GCOMx in bionic applications.

14.
Adv Sci (Weinh) ; 11(19): e2400626, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38476058

RESUMO

Engineering porous organic polymers (POPs) into 1D morphology holds significant promise for diverse applications due to their exceptional processability and increased surface contact for enhanced interactions with guest molecules. This article reviews the latest developments in nanofibrous POPs and their derivatives, encompassing porous organic polymer nanofibers, their composites, and POPs-derived carbon nanofibers. The review delves into the design and fabrication strategies, elucidates the formation mechanisms, explores their functional attributes, and highlights promising applications. The first section systematically outlines two primary fabrication approaches of nanofibrous POPs, i.e., direct bulk synthesis and electrospinning technology. Both routes are discussed and compared in terms of template utilization and post-treatments. Next, performance of nanofibrous POPs and their derivatives are reviewed for applications including water treatment, water/oil separation, gas adsorption, energy storage, heterogeneous catalysis, microwave absorption, and biomedical systems. Finally, highlighting existent challenges and offering future prospects of nanofibrous POPs and their derivatives are concluded.

15.
J Fluoresc ; 23(4): 621-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23475273

RESUMO

Poly(1-amino-5-chloroanthraquinone) (PACA) was firstly synthesized by a chemically oxidative interfacial polymerization. The PACA has been developed as a fluorescent sensor for the determination of Fe(III) in semi-aqueous solution at pH 7.0. The sensor exhibited remarkably high sensitivity toward Fe(3+) since the fluorescence of the polymer could be significantly quenched even though trace Fe(3+) was added. The sensor showed a linear fluorescence emission response over a wide concentration range from 1.0 × 10(-10) to 1.0 × 10(-4) M, with an ultra-low detection limit of 2.0 × 10(-11) M. The quenching of the fluorescence was found to be static one due to the formation of non-fluorescent complex in the ground state.

16.
Int J Mol Sci ; 14(11): 21647-59, 2013 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-24185912

RESUMO

The objective of this study is to develop a structural nanocomposite of multiple components in the form of core-sheath nanofibres using coaxial electrospinning for the fast dissolving of a poorly water-soluble drug quercetin. Under the selected conditions, core-sheath nanofibres with quercetin and sodium dodecyl sulphate (SDS) distributed in the core and sheath part of nanofibres, respectively, were successfully generated, and the drug content in the nanofibres was able to be controlled simply through manipulating the core fluid flow rates. Field emission scanning electron microscope (FESEM) images demonstrated that the nanofibres prepared from the single sheath fluid and double core/sheath fluids (with core-to-sheath flow rate ratios of 0.4 and 0.7) have linear morphology with a uniform structure and smooth surface. The TEM images clearly demonstrated the core-sheath structures of the produced nanocomposites. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results verified that quercetin and SDS were well distributed in the polyvinylpyrrolidone (PVP) matrix in an amorphous state, due to the favourite second-order interactions. In vitro dissolution studies showed that the core-sheath composite nanofibre mats could disintegrate rapidly to release quercetin within 1 min. The study reported here provides an example of the systematic design, preparation, characterization and application of a new type of structural nanocomposite as a fast-disintegrating drug delivery system.


Assuntos
Sistemas de Liberação de Medicamentos , Nanofibras/administração & dosagem , Quercetina/administração & dosagem , Portadores de Fármacos/química , Humanos , Nanocompostos/química , Nanofibras/química , Quercetina/química , Dodecilsulfato de Sódio/química
17.
J Colloid Interface Sci ; 633: 265-274, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36455434

RESUMO

Designing porous FeNC nanomaterials with highly efficient active sites is an effective strategy for constructing high-performance oxygen reduction reaction (ORR) electrocatalysts. N-containing porous organic polymers (POPs) have emerged as promising candidates for the preparation of porous FeNC catalysts. Here, N-rich tripolycyanamide-based microporous polymer (TCAMP)-coated SiO2 nanospheres (SiO2@TACMP) were prepared as the precursors of an Fe-N doped hierarchical meso-micro porous carbon (Fe-N-HMC) electrocatalyst for the ORR. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) characterizations demonstrated that the Fe-N-HMC catalyst possessed a higher content percentage of Fe-Nx active sites and a better distribution of Fe nanoparticles than its Fe-N doped microporous carbon (Fe-N-MC) counterpart. N2 adsorption-desorption isotherm analysis showed that Fe-N-HMC catalyst exhibited a hierarchical meso-micro porous system, with a Brunauer-Emmett-Teller (BET) surface area (SBET) of 733 m2 g-1 (∼2 times of Fe-N-MC's SBET). As a result, Fe-N-HMC catalyst presented a highly efficient ORR performance with a half-wave potential of 0.856 mV, which is similar to the commercial grade 20 wt% Pt/C catalyst and superior to the Fe-N-MC catalyst. Moreover, the as-synthesized Fe-N-HMC catalyst displayed a better durability and methanol tolerance than the commercial Pt/C catalyst. Therefore, Fe-N-HMC shows great promise as an ORR catalyst for fuel batteries and metal-air cells due to its low-cost, high activity, and good stability.

18.
Mater Horiz ; 10(9): 3569-3581, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37306627

RESUMO

Stretchable organohydrogel fibers are attracting considerable interest for next-generation flexible and wearable soft strain sensors due to their excellent stability in harsh environments. However, due to the uniformly distributed ions and reduced number of carriers in the whole material, the sensitivity of organohydrogel fibers under subzero temperature is not desirable, which significantly hinders their practical application. Herein, a newly competitive proton-trapping strategy was designed to obtain anti-freezing organohydrogel fibers for high-performance wearable strain sensors via a simple freezing-thawing process, in which tetraaniline (TANI), serving as the proton trapper, and representing the shortest repeated structural unit of polyaniline (PANI), was physically crosslinked with polyvinyl alcohol (PVA) (PTOH). The as-prepared PTOH fiber exhibited an outstanding sensing performance at -40 °C due to the unevenly distributed ion carriers and the highly breakable proton-migration pathways, with a high gauge factor of 24.6 at a strain of 200-300%. Moreover, the existence of hydrogen bonds between the TANI and PVA chains endowed PTOH with a high tensile strength (1.96 MPa) and toughness (8.0 MJ m-3). Accordingly, strain sensors made from PTOH fibers and knitted textiles could monitor human motions rapidly and sensitively, demonstrating their potential as wearable anti-freezing anisotropic strain sensors.

19.
ACS Appl Mater Interfaces ; 15(38): 45158-45166, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37708412

RESUMO

Modification of the molecular packing of nonfullerene acceptors through fluorination represents one of the most promising strategies to achieve highly efficient organic solar cells (OSCs). In this work, three nonfused electron acceptors, namely, DTCBT-Fx (x = 0, 5, 9) with precisely controlled amounts of fluorine atoms in the side chains are designed and synthesized, and the effect of side chain fluorination is systematically studied. The results demonstrate that the light absorption, energy levels, molecular ordering, and film morphology could be effectively tuned by precisely controlling the side chain fluorination. DTCBT-F5 with an appropriate fluorine functionalization exhibits suitable miscibility with the donor polymer (PM6), leading to diminished charge recombination and improved charge carrier mobility. Consequently, a promising power conversion efficiency of 12.7% was obtained for DTCBT-F5-based solar cells, which outperforms those OSCs based on DTCBT-F0 (11.4%) and DTCBT-F9 (11.6%), respectively. This work demonstrates that precise control of the fluorine functionalization in side chains of nonfused electron acceptors is an effective strategy for realizing highly efficient OSCs.

20.
Nat Commun ; 14(1): 263, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650177

RESUMO

The role of N-heterocyclic carbene, a well-known reactive site, in chemical catalysis has long been studied. However, its unique binding and electron-donating properties have barely been explored in other research areas, such as metal capture. Herein, we report the design and preparation of a poly(ionic liquid)-derived porous organic polycarbene adsorbent with superior gold-capturing capability. With carbene sites in the porous network as the "nanotrap", it exhibits an ultrahigh gold recovery capacity of 2.09 g/g. In-depth exploration of a complex metal ion environment in an electronic waste-extraction solution indicates that the polycarbene adsorbent possesses a significant gold recovery efficiency of 99.8%. X-ray photoelectron spectroscopy along with nuclear magnetic resonance spectroscopy reveals that the high performance of the polycarbene adsorbent results from the formation of robust metal-carbene bonds plus the ability to reduce nearby gold ions into nanoparticles. Density functional theory calculations indicate that energetically favourable multinuclear Au binding enhances adsorption as clusters. Life cycle assessment and cost analysis indicate that the synthesis of polycarbene adsorbents has potential for application in industrial-scale productions. These results reveal the potential to apply carbene chemistry to materials science and highlight porous organic polycarbene as a promising new material for precious metal recovery.

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