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1.
Nat Commun ; 15(1): 4902, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38851770

ABSTRACT

Intrinsically stretchable organic photovoltaics have emerged as a prominent candidate for the next-generation wearable power generators regarding their structural design flexibility, omnidirectional stretchability, and in-plane deformability. However, formulating strategies to fabricate intrinsically stretchable organic photovoltaics that exhibit mechanical robustness under both repetitive strain cycles and high tensile strains remains challenging. Herein, we demonstrate high-performance intrinsically stretchable organic photovoltaics with an initial power conversion efficiency of 14.2%, exceptional stretchability (80% of the initial power conversion efficiency maintained at 52% tensile strain), and cyclic mechanical durability (95% of the initial power conversion efficiency retained after 100 strain cycles at 10%). The stretchability is primarily realised by delocalising and redistributing the strain in the active layer to a highly stretchable PEDOT:PSS electrode developed with a straightforward incorporation of ION E, which simultaneously enhances the stretchability of PEDOT:PSS itself and meanwhile reinforces the interfacial adhesion with the polyurethane substrate. Both enhancements are pivotal factors ensuring the excellent mechanical durability of the PEDOT:PSS electrode, which further effectively delays the crack initiation and propagation in the top active layer, and enables the limited performance degradation under high tensile strains and repetitive strain cycles.

2.
Environ Sci Technol ; 58(14): 6370-6380, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38497719

ABSTRACT

The discovery of the significant lethal impacts of the tire additive transformation product N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-Q) on coho salmon has garnered global attention. However, the bioaccumulation and trophic transfer of tire additives and their transformation products (TATPs) within food webs remain obscure. This study first characterized the levels and compositions of 15 TATPs in the Pearl River Estuary, estimated their bioaccumulation and trophic transfer potential in 21 estuarine species, and identified priority contaminants. Our observations indicated that TATPs were prevalent in the estuarine environment. Eight, six, seven, and 10 TATPs were first quantified in the shrimp, sea cucumber, snail, and fish samples, with total mean levels of 45, 56, 64, and 67 ng/g (wet weight), respectively. N,N'-Diphenyl-p-phenylenediamine (DPPD) and N,N'-bis(2-methylphenyl)-1,4-benzenediamine (DTPD) exhibited high bioaccumulation. Significant biodilution was only identified for benzothiazole, while DPPD and DTPD displayed biomagnification trends based on Monte Carlo simulations. The mechanisms of bioaccumulation and trophodynamics of TATPs could be explained by their chemical hydrophobicity, molecular mass, and metabolic rates. Based on a multicriteria scoring technique, DPPD, DTPD, and 6PPD-Q were characterized as priority contaminants. This work emphasizes the importance of biomonitoring, particularly for specific hydrophobic tire additives.


Subject(s)
Food Chain , Phenylenediamines , Water Pollutants, Chemical , Animals , Bioaccumulation , Environmental Monitoring , Water Pollutants, Chemical/analysis
3.
J Hazard Mater ; 465: 133088, 2024 03 05.
Article in English | MEDLINE | ID: mdl-38016320

ABSTRACT

The substantial utilization of antibiotics causes their "pseudo-persistence" in offshore environments. Published studies on antibiotic surveillance in food webs have primarily emphasized on parent forms; however, the compositions and concentrations of conjugated antibiotics in aquatic organisms remain largely unexplored. This study systematically examined the distribution characteristics and trophodynamics of free antibiotics and their conjugated forms in an estuarine food web. Total antibiotic levels differed insignificantly between the surface and bottom waters. The total mean values of free antibiotics in crabs, fish, shrimps, sea cucumbers, and snails varied from 0.77 to 1.4 ng/g (wet weight). The numbers and values of antibiotics rose in these biological samples after enzymatic hydrolysis. Conjugated antibiotics accounted for 23.8-76.9% of the total antibiotics in the biological samples, revealing that conjugated forms play a non-negligible role in aquatic organisms. More number of antibiotics exhibited bioaccumulation capabilities after enzymatic hydrolysis. In the food web, the free forms of anhydroerythromycin and conjugated forms of trimethoprim and ciprofloxacin underwent trophic dilution, whereas the free forms of trimethoprim and conjugated forms of ofloxacin underwent trophic amplification. The present work provides new insights into the bioaccumulation and trophic transfer of free and conjugated antibiotics in food webs.


Subject(s)
Food Chain , Water Pollutants, Chemical , Animals , Anti-Bacterial Agents/analysis , Bioaccumulation , Multimedia , Water Pollutants, Chemical/analysis , Aquatic Organisms , Fishes , Trimethoprim , Environmental Monitoring , China
4.
Water Res ; 235: 119913, 2023 May 15.
Article in English | MEDLINE | ID: mdl-36996753

ABSTRACT

Steroids have attracted particular attention as environmental contaminants because of their severe endocrine-disrupting effects. Previous studies have predominantly focused on parent steroids; however, the levels and proportions of the free and conjugated forms of their metabolites remain largely unclear, especially in food webs. Here, we first characterized the free and conjugated forms of parent steroids and their metabolites in 26 species in an estuarine food web. The steroids were dominated by their metabolites in water samples, whereas parent compounds were predominant in sediment samples. The total mean steroid concentrations in the biota samples that underwent non-enzymatic hydrolysis decreased in the following order: crabs (27 ng/g) > fish (5.9 ng/g) > snails (3.4 ng/g) > shrimps and sea cucumbers (1.2 ng/g); and those in the biota samples that underwent enzymatic hydrolysis decreased in the following order: crabs (57 ng/g) > snails (9.2 ng/g) > fish (7.9 ng/g) > shrimps and sea cucumbers (3.5 ng/g). The proportion of metabolites in the enzymatic hydrolysis biota samples was higher (38-79%) than that (2.9-65%) in non-enzymatic ones, indicating that the free and conjugated forms of metabolites in aquatic organisms were not negligible. Most synthetic steroids were either bioaccumulative or highly bioaccumulative. Importantly, in the invertebrate food web, 17α-methyltestosterone was biomagnified, while 17ß-boldenone underwent trophic dilution. Although the estuarine water had a median ecological risk level, the health risks via aquatic product consumption were very low. This study provides novel insights into the composition and trophic transfer of steroids in an estuarine food web for the first time and highlights that free and conjugated metabolites should receive more attention, particularly in biota samples.


Subject(s)
Food Chain , Water Pollutants, Chemical , Animals , Environmental Monitoring , Water Pollutants, Chemical/analysis , Fishes , Steroids/metabolism , Water , China
5.
Angew Chem Int Ed Engl ; 59(48): 21499-21504, 2020 Nov 23.
Article in English | MEDLINE | ID: mdl-32725851

ABSTRACT

Graphitic carbon nitride quantum dots (g-CNQDs) are highly promising photoresponsive materials. However, synthesis of monodispersed g-CNQDs remains challenging. Here we report the dual function of MOF [Cu3 BTC2 ] (HKUST-1) as a catalyst and template simultaneously to prepare g-CNQDs under mild conditions. Cyanamide (CA), a graphitic carbon nitride precursor, catalytically dimerized inside the larger MOF cavities at 90 °C and condensed into g-CNQDs at 120 °C in a controlled fashion. The HKUST-1 template was stable under the reaction conditions, leading to uniform g-CNQDs with a particle size of 2.22±0.68 nm. The as prepared g-CNQDs showed photoluminescence emission with a quantum yield of 3.1 %. This concept (MOF dual functionality) for catalyzing CA polycondensation (open metal sites (OMSs) effect) and controlling the produced particle size (pore-templating effect), together with the tunable MOF porosity, is expected to produce unique g-CNQDs with controllable size, morphology, and surface functionality.

6.
Dalton Trans ; 49(28): 9662-9667, 2020 Jul 21.
Article in English | MEDLINE | ID: mdl-32633302

ABSTRACT

Photosynthesis plays a vital role on earth and photo-induced organic reactions have artificially created many valuable materials. However, the photo-induced syntheses of inorganic compounds are much less reported. Herein, we report the photo-assisted synthesis of a mixed-valence polyoxovanadate with the formula [C9H14N]6[V15O36Cl], under AM1.5 irradiation in a N2 atmosphere. Single-crystal X-ray diffraction analysis reveals a hexagonal structure (space group P63/mmc) with cell parameters: a = 14.1100(6) Å, b = 14.1100(6) Å, c = 22.0265(10) Å, and V = 3797.8(4) Å3. UV-Vis and EPR analyses verified that the [V15O36Cl]6- cluster formed within 0.5 h; powder XRD results indicated that the crystalline phase appeared after irradiation for 9.5 h (200 mW cm-2). These findings suggested that the nucleation and crystallization processes took longer than [V15O36Cl]6- cluster formation and dominated the [C9H14N]6[V15O36Cl] crystal formation. This primary work could open the door for the syntheses of inorganic compounds using photo-assisted reactions instead of conventional thermo-driving syntheses.

7.
Nat Commun ; 11(1): 3124, 2020 06 19.
Article in English | MEDLINE | ID: mdl-32561736

ABSTRACT

Adsorption of guest molecules by porous materials proceeds in a spontaneous exothermic way, whereas desorption usually requires external energy input as an endothermic process. Reducing such energy consumption makes great sense in practice. Here we report the reversible and automatic methanol (MeOH) adsorption/release in an ionic hydrogen-bonded organic framework (iHOF) constructed from guanidinium cation and borate anion ([B(OCH3)4]3[C(NH2)3]4Cl•4CH3OH, termed Gd-B) at ambient condition. The metastable Gd-B automatically releases all sixteen MeOH molecules (63.4 wt%) via desorption and tetra-methyl borate hydrolysis at ambient atmosphere and the structure can be recovered when re-exposed to MeOH vapor or liquid, mimicking combustible ice behavior but at ambient condition. Reversible capture/release of four guest MeOH molecules is also realized without destroying its crystal structure. The combustible Gd-B paves a way for exploring metastable iHOF materials as carrier for alternative energy source and drug delivery etc.

8.
ChemSusChem ; 13(11): 2945-2951, 2020 Jun 08.
Article in English | MEDLINE | ID: mdl-32240576

ABSTRACT

Efficient utilization of solar energy for water evaporation is an advanced and environmentally friendly technology to address the crisis of global drinking water shortages. This study concerns an efficient solar vapor generator comprised of a light-absorbing and photothermal hybrid compound [Ni(Phen)3 ][V14 O34 Cl]Cl (NiV14 ) confined in mesoporous and hydrophilic glass (meso-glass). The generator is floated in water by supporting it on a domestic melamine-formaldehyde (MF) foam to ensure evaporation at the water-air interface. The porous structures and poor thermal conductivities of the meso-glass and MF foam contribute to enabling a consistent water supply, strong solar thermal localization, and less heat dissipation and convection. Associated with the strong photothermal role of NiV14 , these synergistic effects lead to a water evaporation rate of 14.38 kg m-2 h-1 with total water evaporation efficiency of 111.4% under 6 suns and a daily solar water purification yield of 42.00 L m-2 under 1 sun irradiation. This solar evaporation system shows great promise for high-efficiency water purification application.

9.
Nat Commun ; 10(1): 2500, 2019 06 07.
Article in English | MEDLINE | ID: mdl-31175298

ABSTRACT

Precise control of interlayer spacing and functionality is crucial in two-dimensional material based membrane separation technology. Here we show anion intercalation in protonated graphite phase carbon nitride (GCN) that tunes the interlayer spacing and functions of GCN-based membranes for selective permeation in aqueous/organic solutions. Sulfate anion intercalation leads to a crystalline and amphipathic membrane with an accessible interlayer spacing at ~10.8 Å, which allows high solvent permeability and sieves out the solutes with sizes larger than the spacing. We further extend the concept and illustrate the example of GCN-based chiral membrane via incorporating (1R)-(-)-10-camphorsulfonic anion into protonated GCN layers. The membrane exhibits a molecular weight cutoff around 150 among various enantiomers and highly enantioselective permeation towards limonene racemate with an enantiomeric excess value of 89%. This work paves a feasible way to achieve water purification and chiral separation technologies using decorated laminated membranes.

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