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1.
Nat Commun ; 15(1): 4213, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760369

RESUMEN

Nanofluidic membranes have demonstrated great potential in harvesting osmotic energy. However, the output power densities are usually hampered by insufficient membrane permselectivity. Herein, we design a polyoxometalates (POMs)-based nanofluidic plasmonic electron sponge membrane (PESM) for highly efficient osmotic energy conversion. Under light irradiation, hot electrons are generated on Au NPs surface and then transferred and stored in POMs electron sponges, while hot holes are consumed by water. The stored hot electrons in POMs increase the charge density and hydrophilicity of PESM, resulting in significantly improved permselectivity for high-performance osmotic energy conversion. In addition, the unique ionic current rectification (ICR) property of the prepared nanofluidic PESM inhibits ion concentration polarization effectively, which could further improve its permselectivity. Under light with 500-fold NaCl gradient, the maximum output power density of the prepared PESM reaches 70.4 W m-2, which is further enhanced even to 102.1 W m-2 by changing the ligand to P5W30. This work highlights the crucial roles of plasmonic electron sponge for tailoring the surface charge, modulating ion transport dynamics, and improving the performance of nanofluidic osmotic energy conversion.

2.
J Colloid Interface Sci ; 666: 648-658, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38570207

RESUMEN

Interfacial regulation is key to photocatalytic performance, yet modulating interfacial charge transfer in heterostructures remains challenging. Herein, a novel nanoflower-like FeP/ZnIn2S4 Ohm heterostructure is first designed, with Zn atoms in ZnIn2S4 (ZIS) acting as potential anchoring sites around P atoms, forming liganded Zn-P bonds. Combining 1D FeP nanowires and 2D ZIS nanosheets enhances the mobility of photogenerated electrons. The synergistic chain-type "electron pickup" mechanism of the Ohm heterojunction coupled with the Zn-P bond speeds up electron transport at the interface. The Ohm heterojunction initiates an internal electric field, creating a driving force to further transfer photogenerated electrons through the Zn-P rapid electron transport channel to FeP, which acts as a reservoir for active sites to release H2. The optimized FeP/ZIS demonstrates a remarkable H2 evolution rate at 4.36 mmol h-1 g-1, 3.6 times that of pristine ZIS. This work provides novel insights into optimizing photocarrier dynamics via interfacial microenvironment modulation.

3.
ACS Nano ; 17(12): 11869-11881, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37289089

RESUMEN

Photocatalytic reduction of CO2 to value-added solar fuels is of great significance to alleviate the severe environmental and energy crisis. Herein, we report the construction of a synergistic silver nanoparticle catalyst with adjacent atomic cobalt-silver dual-metal sites on P-doped carbon nitride (Co1Ag(1+n)-PCN) for photocatalytic CO2 reduction. The optimized photocatalyst achieves a high CO formation rate of 46.82 µmol gcat-1 with 70.1% selectivity in solid-liquid mode without sacrificial agents, which is 2.68 and 2.18-fold compared to that of exclusive silver single-atom (Ag1-CN) and cobalt-silver dual-metal site (Co1Ag1-PCN) photocatalysts, respectively. The closely integrated in situ experiments and density functional theory calculations unravel that the electronic metal-support interactions (EMSIs) of Ag nanoparticles with adjacent Ag-N2C2 and Co-N6-P single-atom sites promote the adsorption of CO2* and COOH* intermediates to form CO and CH4, as well as boost the enrichment and transfer of photoexcited electrons. Moreover, the atomically dispersed dual-metal Co-Ag SA sites serve as the fast-electron-transfer channel while Ag nanoparticles act as the electron acceptor to enrich and separate more photogenerated electrons. This work provides a general platform to delicately design high-performance synergistic catalysts for highly efficient solar energy conversion.

4.
Chemosphere ; 307(Pt 4): 135915, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35977577

RESUMEN

Tri(2-chloroisopropyl) phosphate (TCPP), a common organophosphate flame retardant, was frequently detected in the environment and posed threats to human health. In this work, the main component of ilmenite FeTiO3 was synthesized by the sol-gel method and employed as the catalyst for the degradation of TCPP by activating persulfate (PS) under UV irradiation. The degradation processes were fitted by the pseudo-first-order kinetic. The kobs value in UV/FeTiO3/PS system was up to 0.0056 min-1 and much higher than that in UV/PS (0.0014 min-1), UV/FeTiO3 (0.0012 min-1) and FeTiO3/PS (0.0016 min-1) systems, demonstrating a distinct synergistic effect in TCPP removal. The degradation efficiency of TCPP increased with the increase of UV intensity, PS concentration and catalyst dosage, and with the decrease of pH. By quenching experiment and EPR analysis, ·OH was confirmed to be the dominant radical in the reaction of the UV/FeTiO3/PS system. The possible degradation pathways of TCPP were dechlorination, dealkylation, and further oxidation of alkyl groups based on the theoretical calculation of frontier molecular orbits. The toxicity of degradation intermediates evaluated by luminescence inhibition rate of photoluminescence was higher than TCPP. Thus, TCPP can be degraded in the UV/FeTiO3/PS system effectively at the premise of introducing controlling measures to reduce the toxicity of degradation intermediates.


Asunto(s)
Retardadores de Llama , Contaminantes Químicos del Agua , Retardadores de Llama/análisis , Humanos , Hierro , Organofosfatos/química , Oxidación-Reducción , Fosfatos/química , Titanio , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisis
5.
Int J Gen Med ; 15: 513-522, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35058708

RESUMEN

PURPOSE: This study aims to explore the psychological status of suspected COVID-19 patients during quarantine and put forward a new yet effective psychological nursing strategy for intervention. PATIENTS AND METHODS: We performed a retrospective study with suspected COVID-19 patients who were hospitalized to the two hospitals of Hunan province, China and accepted the intervention of psychological nursing from 01/2020 to 03/2020. The control group received routine psychological nursing care and the observation group received the new psychological nursing intervention according to Pygmalion effect. RESULTS: A total of 89 objects were included in the analysis. Results of the questionnaire before intervention showed that the majority of isolated suspected COVID-19 patients showed negative emotions, with the incidence of depression (51.69%), anxiety (14.617%), inverted provocation (22.47%), extraverted provocation (25.84%). And the extraverted provocation scores of female patients was significantly higher than that of male counterparts (P < 0.05). At discharge, compared with the control group, the scores of depression, anxiety, introversion and extraversion of patients in the observation group were significantly lower after nursing intervention based on Pygmalion effect. The satisfaction rate of psychological care based on Pygmalion effect was 86.66%. CONCLUSION: Suspected COVID-19 patients tend to show the symptoms of depression, anxiety and irritation during quarantine. The psychological nursing based on Pygmalion effect is helpful to alleviate their negative emotions.

6.
J Colloid Interface Sci ; 612: 722-736, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35032927

RESUMEN

A novel 2D/3D S-scheme carbon nitride/iodine-deficient bismuth oxyiodide (g-C3N4/BiO1.2I0.6) heterojunction was constructed for the first time by calcining a mixture of g-C3N4 nanosheets and flower-like BiOI. Irradiated by visible light, this g-C3N4/BiO1.2I0.6 heterojunction exhibited excellent photocatalytic hydrogen production and BPA degradation activity with high cycle stability. In particular, the photocatalytic activity of 0.2-C3N4/BiO1.2I0.6 could reach 1402.7 µmol g-1 h-1 (hydrogen production rate) and 0.01155 min-1 (apparent rate of bisphenol A degradation), which were 3.5 and 3.2 times that of g-C3N4 respectively. The remarkable photocatalytic performance was due to the efficient charge separation of g-C3N4/BiO1.2I0.6 and the formation of S-scheme heterojunction, which maintained strong photocatalytic reduction and oxidation potentials. Noticeably, the charge density difference and band offsets of the g-C3N4/BiO1.2I0.6 were calculated. The results revealed that a built-in electric field (IEF) was created. The values of the valence band offset (ΔEVBO) and the conduction band offset (ΔECBO) were -0.84 and -1.27 eV, respectively, which further demonstrated the formation of S-scheme photocatalytic charge transfer mechanism.

7.
J Colloid Interface Sci ; 610: 280-294, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34922080

RESUMEN

Based on single metal-organic framework (MOF) composite catalyst ZIF-67/g-C3N4 (ZG), the composite catalysts ZIF-67/MOF-74(Ni)/g-C3N4 (ZNG) and ZIF-67/MIL-100(Fe)/g-C3N4 (ZMG) with double MOFs were synthesized, used to effectively activate peroxymonosulfate (PMS) for degrade venlafaxine (VEN). Various characterization methods (XRD, FT-IR, Raman, SEM, EDS, TEM and TG) showed that ZIF-67 and g-C3N4; ZIF-67, MOF-74(Ni) and g-C3N4; as well as ZIF-67, MIL-100(Fe) and g-C3N4 successfully formed heterostructures. The series of catalytic degradation results showed that within 120 min, the degradation rate of VEN by ZMG achieved 100% and the mineralization rate reached 51.32%. The removal rate of VEN by ZNG was 91.38%, while that by ZG was only 27.75%. Free radical quenching tests and EPR further confirmed the production of OH and SO4-, which could be conducive to the degradation of VEN. The mechanism analysis of PMS activation confirmed that the interaction of Fe2+/Co3+ was stronger than that of Ni2+/Co3+, and it was an important driving force to significantly enhance the synergistic effect. Finally, Gauss theory calculation and HPLC-MS/MS were used to analyze the intermediate products of VEN. It was verified that the main chemical reactions in the degradation process of VEN were hydroxylation, dehydration, demethylation and tertiary amine substitution.


Asunto(s)
Estructuras Metalorgánicas , Antidepresivos , Peróxidos , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría de Masas en Tándem , Clorhidrato de Venlafaxina
8.
Sci Total Environ ; 804: 150215, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34798743

RESUMEN

As an emerging group of visible-light-driven photocatalysts, bismuth-based complex oxides have attracted considerable attention owing to their outstanding photo-oxidation ability and high performance in decomposition of organic contaminants and water oxidation via photocatalytic processes. However, the relatively low level of the conduction band limits their further application in photocatalytic hydrogen evolution and overall water splitting processes. In this paper, three representative and most-studied Bi-based complex oxides of BiOX (X = Cl, Br, I)/BiFeO3/Bi2WO6 are discussed mainly for environmental pollutants degradation and oxygen generation from water splitting. We present a comprehensive overview of their fundamental compositions, electronic structures and synthesis strategies. On the basis of analyzing the structural-property-activity relationships, detailed approaches for enhancement of their photocatalytic performance have been addressed and compared including morphology/facets control, heterostructures construction and introduction of oxygen vacancies. In addition, several techniques such as engineering energy band and building a Z-scheme system have been proposed to modulate the energy band positions of the photocatalysts and overcome the bottleneck to realize overall water splitting into H2 and O2 simultaneously. Finally, remarks on the current challenges, research directions and future perspectives are presented to provide guidance for designing and configuring highly efficient solar-light-driven photocatalysts in the field of environmental purification and energy conversion.

9.
J Colloid Interface Sci ; 599: 23-33, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33933794

RESUMEN

Nanorod-like CoP nanoparticles were fabricated from different precursors of Co(OH)2 and Co3O4 by gas-solid reaction, then further embedded into g-C3N4 nanosheets to form intimate heterojunctions via the (011) crystal planes of CoP nanoparticles. The heterojunction hybrid obtained from Co(OH)2 exhibits superior activity in photo, electro and photoelectrochemical water splitting processes. In photocatalytic water half-splitting for hydrogen evolution reaction, the as-obtained 0.5% CoP-CN achieved a rate at 959.4 µmol·h-1·g-1 and 59.1 µmol·h-1·g-1 when irradiated by simulated sunlight and visible light respectively, almost 3.1 times and 15.8 times that of pristine g-C3N4, For photocatalytic water full-splitting, a stoichiometric evolution of H2 (14.7 µmol·h-1·g-1) and O2 (7.6 µmol·h-1·g-1) was observed on 3%Pt-0.5% CoP-CN composite. The onset potential for electrochemical HER process was drastically reduced after deposition with 0.5% CoP. Meanwhile, a higher photocurrent response and larger anodic photocurrent was detected over 0.5% CoP-CN photoanode during the photoelectrochemical water splitting process, relative to pristine g-C3N4 and its analogues. The comprehensive enhancements for catalytic activity of 0.5% CoP-CN could be attributed to its reduced over-potentials, more negative photo-reductive potentials, boosted interfacial charge transfer efficiency, as well as a much higher solar to hydrogen efficiency. The contrastive redox roles of CoP in both photocatalytic water half-splitting and full-splitting processes have been fully explored and revealed. This design on covalent organic framework of highly efficient CoP-based heterojunctions holds great promise for direct water splitting applications in utilizing solar energy.

10.
RSC Adv ; 10(44): 26090-26101, 2020 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-35519775

RESUMEN

Cadmium (Cd) pollution poses a serious risk to human health and ecological security. Bioremediation can be a promising and effective remediation technology for treating Cd contaminated soils. In this study, seven heterotrophic strains were isolated from Cd contaminated soil and 7 autotrophic strains were isolated from acid mine drainage. Cd removal efficiencies were compared after leaching with autotrophic bacteria (Att-sys), heterotrophic isolates (Htt-sys) and cooperative leaching systems (Co-sys) in laboratory agitating reactors. The results indicated that Cd removal efficiency of Co-sys (32.09%) was significantly higher than that of Att-sys (23.24%) and Htt-sys (0.74%). By analyzing the soil microbial community in different bioleaching systems, we found that the addition of heterotrophic isolates significantly promoted the growth of some heavy metal resistant inhabitants (Massilia, Alicyclobacillus, Micromonospora, etc.), and Co-sys had a minor effect on the growth of soil indigenous microbes. In Co-sys, the content of the four Cd fractions all decreased compared with other leaching systems. The analysis of soil physicochemical parameters during the leaching process showed that pH and ORP (oxidation reduction potential) were not the only determinants for Cd removal efficiency in Co-sys, synergistic metabolic activities of autotrophic and heterotrophic strains may be other determinants. This study demonstrated that cooperative bioremediation may prove to be a safe and efficient technique for field application in heavy metal soil pollution.

11.
J Colloid Interface Sci ; 532: 321-330, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30096526

RESUMEN

Photocatalysis has been believed as one of the green and sustainable avenues to address energy and environmental crises by converting solar energy to chemical energy via reactions. Temperature is usually a vital factor controlling kinetics and thermodynamics of a reaction, but it has been less investigated in photocatalysis. In this work, the effect of reaction temperature on photocatalysis was investigated in a simple process, photocatalytic degradation of Congo Red (CR) on three typical catalysts, g-C3N4, TiO2 and ZnO, to differentiate the interfacial radical generation and reaction mechanism. The results showed that the temperature has a positive effect on the photocatalytic activity of the three catalysts. The scavenger experiments at various temperatures indicated that the generation of reactive species from the three photocatalysts is different and that the free radicals can be produced more quickly at higher temperatures, causing improved activities in photocatalysis. However, photocurrent analysis and EIS at various temperatures showed that the temperature had a different effect on recombination rate and transfer barriers of the charge carriers from each catalyst. Therefore, the dramatic enhancement in photodegradation activities probably originated from a novel mechanism of the photothermocatalytic oxidation. The interfacial reaction and mechanism from the influence of reaction temperature on the photocatalytic process was proposed.

12.
Nanomaterials (Basel) ; 7(3)2017 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-28336897

RESUMEN

Three-dimensional flower-like BiOI/BiOX (X = Br or Cl) hybrids were synthesized via a facile one-pot solvothermal approach. With systematic characterizations by X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission electron microscopy (TEM), the Brunauer-Emmett-Teller (BET)specific surface area, X-ray photoelectron spectroscopy (XPS), and the UV-Vis diffuse reflectance spectra (DRS), the BiOI/BiOCl composites showed a fluffy and porous 3-D architecture with a large specific surface area (SSA) and high capability for light absorption. Among all the BiOX (X = Cl, Br, I) and BiOI/BiOX (X = Cl or Br) composites, BiOI/BiOCl stands out as the most efficient photocatalyst under both visible and UV light irradiations for methyl orange (MO) oxidation. The reaction rate of MO degradation on BiOI/BiOCl was 2.1 times higher than that on pure BiOI under visible light. Moreover, BiOI/BiOCl exhibited enhanced water oxidation efficiency for O2 evolution which was 1.5 times higher than BiOI. The enhancement of photocatalytic activity could be attributed to the formation of a heterojunction between BiOI and BiOCl, with a nanoporous structure, a larger SSA, and a stronger light absorbance capacity especially in the visible-light region. The in situ electron paramagnetic resonance (EPR) revealed that BiOI/BiOCl composites could effectively evolve superoxide radicals and hydroxyl radicals for photodegradation, and the superoxide radicals are the dominant reactive species. The superb photocatalytic activity of BiOI/BiOCl could be utilized for the degradation of various industrial dyes under natural sunlight irradiation which is of high significance for the remediation of industrial wastewater in the future.

13.
Sci Rep ; 5: 15765, 2015 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-26497265

RESUMEN

A facile method to synthesize a TiO2/PEDOT:PSS hybrid nanocomposite material in aqueous solution through direct current (DC) plasma processing at atmospheric pressure and room temperature has been demonstrated. The dispersion of the TiO2 nanoparticles is enhanced and TiO2/polymer hybrid nanoparticles with a distinct core shell structure have been obtained. Increased electrical conductivity was observed for the plasma treated TiO2/PEDOT:PSS nanocomposite. The improvement in nanocomposite properties is due to the enhanced dispersion and stability in liquid polymer of microplasma treated TiO2 nanoparticles. Both plasma induced surface charge and nanoparticle surface termination with specific plasma chemical species are proposed to provide an enhanced barrier to nanoparticle agglomeration and promote nanoparticle-polymer binding.

14.
J Hazard Mater ; 142(1-2): 208-15, 2007 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-16982137

RESUMEN

TiO2 thin films were deposited on granular activated carbon by a dip-coating method at low temperature (373 K), using microwave radiation to enhance the crystallization of titania nanoparticles. Uniform and continuous anatase titania films were deposited on the surface of activated carbon. BET surface area of TiO2-mounted activated carbon (TiO2/AC) decreased a little in comparison with activated carbon. TiO2/AC possessed strong optical absorption capacity with a band gap absorption edge around 360 nm. The photocatalytic activity did not increase when the as-synthesized TiO2/AC was thermally treated, but was much higher than commercial P-25 in degradation of phenol by irradiation of electrodeless discharge lamps (EDLs).


Asunto(s)
Carbono/química , Frío , Microondas , Fotoquímica , Titanio/química , Adsorción , Catálisis , Microscopía Electrónica de Rastreo , Fenol/química , Difracción de Rayos X
15.
Huan Jing Ke Xue ; 27(9): 1808-13, 2006 Sep.
Artículo en Chino | MEDLINE | ID: mdl-17117637

RESUMEN

Experimental study on microwave assisted photocatalytic degradation of phenol in aqueous solution was carried out with modified domestic microwave oven, electrodeless discharge lamps (EDLs) and TiO2 catalyst. Results showed that the removal rate of phenol in the MAPC process was 92% after 30 min reaction. Loss of total organic carbon (TOC) was 84% . The optimal conditions for the MAPC method were 10 mg/L phenol, 900 W MW output energy, 50 mL solution volume, EDLs-3, 1-4 g/l. catalyst dosage and 15 mL/min of flowing velocity in the circulating mode. The MAPC process was promising in treating phenolic waste water.


Asunto(s)
Microondas , Fenol/química , Titanio/química , Contaminantes Químicos del Agua/química , Catálisis/efectos de la radiación , Oxidación-Reducción , Fotoquímica , Fotólisis/efectos de la radiación , Purificación del Agua/instrumentación , Purificación del Agua/métodos
16.
Huan Jing Ke Xue ; 27(2): 347-50, 2006 Feb.
Artículo en Chino | MEDLINE | ID: mdl-16686203

RESUMEN

In order to detect the permethrin (Py) residue in environment samples, Ovalbumin(OVA)was used as protein carrier to couple with semi-antigen permethrin by active ester method. Indirect competitive ELISA (icELISA) was established. The most appropriate titration of coating antigen was 0.45 microg/mL and optimal dilution was 1/2 500 correspondingly. The standard curve of icELISA was also established and the curve indicated that the lowest detection limit was 0.l microg/mL, the curve had a favorable linear relation with the concentration range of 10 to approximately 800 microg/mL, recoveries of permethrin (>97%) were satisfactory.


Asunto(s)
Insecticidas/análisis , Permetrina/análisis , Residuos de Plaguicidas/análisis , Piretrinas/análisis , Ensayo de Inmunoadsorción Enzimática/métodos
17.
J Hazard Mater ; 133(1-3): 162-6, 2006 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-16297536

RESUMEN

Photocatalytic degradation of methylene blue (MB) in TiO(2) aqueous suspensions using microwave (MW) powered electrodeless discharge lamps (EDLs) was studied. MB of initial concentration 100 mg/l was mainly decomposed in the process of photocatalytic degradation using EDLs (PCD/EDLs) after 15 min of irradiation. The corresponding mineralization efficiency was 45%. The influence of factors as EDLs, solution volume and TiO(2) catalyst dosage on the decomposition of MB in the PCD/EDLs process was also investigated. The optimal decomposition efficiency was observed when EDLs-4 (four 10 mm x 50 mm EDLs), solution volume of 50 ml and TiO(2) catalyst dosage of 1-4 g/l were used in the study. The PCD/EDLs process was promising in treating MB polluted water.


Asunto(s)
Azul de Metileno/química , Microondas , Titanio/química , Catálisis , Electrodos , Peso Molecular , Fotoquímica , Suspensiones/química
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