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1.
Small ; 19(39): e2301121, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37271929

RESUMO

Optimizing catalysts for competitive photocatalytic reactions demand individually tailored band structure as well as intertwined interactions of light absorption, reaction activity, mass, and charge transport.  Here, a nanoparticulate host-guest structure is rationally designed that can exclusively fulfil and ideally control the aforestated uncompromising requisites for catalytic reactions. The all-inclusive model catalyst consists of porous Co3 O4 host and Znx Cd1- x S guest with controllable physicochemical properties enabled by self-assembled hybrid structure and continuously amenable band gap. The effective porous topology nanoassembly, both at the exterior and the interior pores of a porous metal-organic framework (MOF), maximizes spatially immobilized semiconductor nanoparticles toward high utilization of particulate heterojunctions for vital charge and reactant transfer. In conjunction, the zinc constituent band engineering is found to regulate the light/molecules absorption, band structure, and specific reaction intermediates energy to attain high photocatalytic CO2 reduction selectivity. The optimal catalyst exhibits a H2 -generation rate up to 6720 µmol g-1 h-1 and a CO production rate of 19.3 µmol g-1 h-1 . These findings provide insight into the design of discrete host-guest MOF-semiconductor hybrid system with readily modulated band structures and well-constructed heterojunctions for selective solar-to-chemical conversion.

2.
J Sep Sci ; 43(13): 2550-2557, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32246888

RESUMO

In this study, novel photo-stimulated molecularly imprinted polymers based on magnetic mesoporous carrier surface were developed for selective identification and intelligent separation of sulfamerazine in complex samples. The photosensitive monomer of the molecularly imprinted polymers was azobenzene derivative 5-[(4-(methacryloyloxy)phenyl) diazenyl] isophthalic acid with stimulus reaction mechanisms, which has photoisomerization between trans and cis for N=N bonds. Further, the properties of the photo-stimulated molecularly imprinted polymers were further evaluated through several sets of adsorption experiments. It illustrated that the maximum adsorption amount is 0.45 mmol/L. By ultraviolet spectrophotometry, the material reaches typical characteristic peaks of photo sensitivity, and the cycle time is 16 min. Three adsorption and desorption processes were repeated, the adsorption rate reached 34.4%. Overall, the photo-stimulated molecularly imprinted polymers can enrich and separate determine sulfamerazine with high selectivity, which have good recovery for real samples.

3.
Sci Total Environ ; 928: 172411, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608898

RESUMO

Exposure to diisodecyl phthalate (DIDP) during early pregnancy may be a risk factor for depressive behavior in offspring. While ozone (O3) exposure also raises the probability of depressive behavior during the preceding DIDP-induced process. In the present study, we investigated the effects of prenatal exposure to DIDP and O3 on the development of depressive-like behavior in offspring mice. The study found that prenatal exposure to both DIDP and O3 significantly increased depressive-like behavior in the offspring mice compared to either DIDP or O3 alone. Prenatal exposure to DIDP and O3 obviously increased the levels of corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and cortisol, and decreased the levels of brain-derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT), dopamine (DA) and norepinephrine (NE) in the brain tissues of offspring mice. Transcriptome analysis further revealed significant alterations in genes related to oxidative stress and TWIST1 (a helix-loop-helix transcription factor) in response to the combined exposure to DIDP and O3. HPA axis activation, dysregulation of neurodevelopmental factors, oxidative stress and TWIST1 involvement, collectively contributed to the development of depression-like behaviors in offspring mice following prenatal exposure to DIDP and O3. Moreover, the study also verified the potential role of oxidative stress using vitamin E as an antioxidant. The findings provide valuable evidence for the relationship between co-exposure to DIDP and O3 and depression, highlighting the importance of considering the combined effects of multiple environmental pollutants in assessing their impact on mental health outcomes.


Assuntos
Depressão , Estresse Oxidativo , Ozônio , Ácidos Ftálicos , Efeitos Tardios da Exposição Pré-Natal , Animais , Ozônio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Feminino , Gravidez , Camundongos , Ácidos Ftálicos/toxicidade , Depressão/induzido quimicamente , Poluentes Atmosféricos/toxicidade , Comportamento Animal/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Exposição Materna/efeitos adversos
4.
Small Methods ; 5(5): e2001200, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34928082

RESUMO

Freshwater production is one of the biggest global challenges today. Though desalination can provide a climate-independent source of clean water, the process requires a high energy consumption. Emerging advancement of photothermal nanomaterials and the urgent demand for a green technology transition have reinvigorated the established solar distillation technology. The current development of photothermal vaporization focuses on material innovation and interfacial heating, which largely emphasizes vapor generation efficiency, without considering pragmatic water collection. Moreover, salt accumulation is another critical issue of seawater solar-driven vaporization. The incorporation of photothermal materials into a photothermal membrane distillation (PMD) solar evaporator design harmoniously resolves these issues through combination of renewable energy and efficient interfacial distillation, to achieve the ultimate goal of practical saline water into freshwater conversion. At this juncture, it is imperative to review the recent opportunities and progresses of the PMD system. Here, the fundamental photothermal processes, strategies for efficient evaporator design, evaluation of various criteria for photothermal material incorporation with desired properties, discussions on desalination, water treatment, and energy generation applications are covered. Guidelines in material and system designs to further advance the PMD system that is highly promising in delivering portable water for both large-scale and decentralized systems are provided.

5.
Adv Sci (Weinh) ; 8(19): e2101232, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34363347

RESUMO

Solar-driven water evaporation and valuable fuel generation is an environmentally friendly and sustainable way for clean water and energy production. However, a few bottlenecks for practical applications are high-cost, low productivity, and severe sunlight angle dependence. Herein, solar evaporation with enhanced photocatalytic capacity that is light direction insensitive and of efficiency breakthrough by virtue of a three-dimensional (3D) photothermal catalytic spherical isotopic evaporator is demonstrated. A homogeneous layer of microfluidic blow spun polyamide nanofibers loaded with efficient light absorber of polypyrrole nanoparticles conformally wraps onto a lightweight, thermal insulating plastic sphere, featuring favorable interfacial solar heating and efficient water transportation. The 3D spherical geometry not only guarantees the omnidirectional solar absorbance by the light-facing hemisphere, but also keeps the other hemisphere under shadow to harvest energy from the warmer environment. As a result, the light-to-vapor efficiency exceeds the theoretical limit, reaching 217% and 156% under 1 and 2 sun, respectively. Simultaneously, CO2 photoreduction with generated steam reveals a favorable clean fuels production rate using photocatalytic spherical evaporator by secondary growth of Cu2 O nanoparticles. Finally, an outdoor demonstration manifests a high evaporation rate and easy-to-perform construction on-site, providing a promising opportunity for efficient and decentralized water and clean fuel production.

6.
Adv Mater ; 31(37): e1903605, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31364796

RESUMO

Converting and storing intermittent solar energy into stable chemical fuels of high efficiency depend crucially on harvesting excess energy beyond the conventional ultraviolet light spectrum. The means of applying highly efficient solar-thermal conversion on practical electricity-driven water splitting could be a significant stride toward this goal, while some bottlenecks remain unresolved. Herein, photothermic electrocatalytic oxygen and hydrogen evolution reactions are proposed, which bestow a distinctive exothermic activation and electrochemical reactivity in a reconstructed electrolyzer system, and which are poised for efficient renewable energy production. Attributed to the synergistic in situ coupling of the N-doped carbon, metallic alloy and oxides, in view of their broadband light absorption, high electrochemical surface area, and efficient charge transfer attributes, the hybrid photothermal electrocatalytic electrode simultaneously satisfies efficient photon-to-heat conversion and augmented electrochemical catalytic activity. Finally, a system level design of an appropriate photothermally mediated electrolytic cell with close-proximity light-illumination window along with a low-thermal-emittance electrolyte separator that preserve an overall large localized thermal gradient and efficient mass transport is devised. Such a photothermally mediated electrocatalytic system presented here may open up new avenues for the development of solar-thermal energy utilization in other forms.

7.
Adv Mater ; 30(47): e1802894, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30133029

RESUMO

Utilization of diffusive solar energy through photocatalytic processes for environmental purification and fuel production has long been pursued. However, efficient capture of visible-near-infrared (NIR) photons, especially for those with wavelengths longer than 600 nm, is a demanding quest in photocatalysis owing to their relatively low energy. In recent years, benefiting from the advances in photoactive material design, photocatalytic reaction system optimization, and new emerging mechanisms for long-wavelength photon activation, increasing numbers of studies on the harnessing of visible-NIR light for solar-to-chemical energy conversion have been reported. Here, the aim is to comprehensively summarize the progress in this area. The main strategies of the long-wavelength visible-NIR photon capture and the explicitly engineered material systems, i.e., narrow optical gap, photosensitizers, upconversion, and photothermal materials, are elaborated. In addition, the advances in long-wavelength light-driven photo- and photothermal-catalytic environmental remediation and fuel production are discussed. It is anticipated that this review presents the forefront achievements in visible-NIR photon capture and at the same time promotes the development of novel visible-NIR photon harnessing catalysts toward efficient solar energy utilization.

8.
Adv Mater ; 27(47): 7713-9, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26501718

RESUMO

A macroporous carbon network combined with mesoporous catalyst immobilization by a template method gives a metal-oxide-organic framework (MoOF) foam microreactor that readily soaks up pollutants and localizes solar energy in itself, leading to effective degradation of water pollutants (e.g., methyl orange (MO) and also hydrogen generation. The cleaned-up water can be removed from the microreactor simply by compression, and the microreactor used repeatedly.


Assuntos
Desenho de Fármacos , Poluentes Ambientais/química , Hidrogênio/química , Compostos Organometálicos/química , Processos Fotoquímicos , Luz Solar , Absorção Fisico-Química , Catálise , Poluentes Ambientais/isolamento & purificação , Modelos Moleculares , Conformação Molecular
9.
Nanoscale ; 6(21): 12655-64, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25201290

RESUMO

In this work, we demonstrate the fine structural tuning of metal-metal oxide heterostructure with regards to the individual tuning of the various core and shell components from shell thickness to metal core constitution. Furthermore, we deliberately engineered spatially confined and clustered Au nanoparticles in the core of a porous shell structure without the assistance of template or linker. Our findings unambiguously highlight that whilst it is important to incorporate metal nanoparticles into metal oxide for higher photocatalytic performance through enhanced light absorption and charge separation, the "whereabout" and clustering of Au nanoparticles affect the photocatalytic performance. Furthermore, we also prove the enhanced and prolonged catalytic activity of spatially confined metal cores over conventional surface loaded metal particles, which originates from the structural stability and optimized contact interface for heterojunction-induced charge transfer. The present well-controlled synthetic route can offer a facile and valuable way to tune and probe specific structure in relation to nanoscale light-matter manipulation and solar-to-chemical energy conversion studies.

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