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1.
Small ; 20(30): e2310644, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38386306

RESUMO

Mixed matrix composite membranes (MMCMs) have shown advantages in reducing VOCs and CO2 emissions. Suitable composite layer, substrate, and good compatibility between the filler and the matrix in the composite layer are critical issues in designing MMCMs. This work develops a high-performance UiO-66-NA@PDMS/MCE for VOCs adsorption and CO2 permea-selectivity, based on a simple and facile fabrication of composite layer using amidation-reaction approach on the substrate. The composite layer shows a continuous morphological appearance without interface voids. This outstanding compatibility interaction between UiO-66-NH2 and PDMS is confirmed by molecular simulations. The Si─O functional group and UiO-66-NH2 in the layer leads to improved VOCs adsorption via active sites, skeleton interaction, electrostatic interaction, and van der Waals force. The layer and ─CONH─ also facilitate CO2 transport. The MMCMs show strong four VOCs adsorption and high CO2 permeance of 276.5 GPU with a selectivity of 36.2. The existence of VOCs in UiO-66-NA@PDMS/MCE increases the polarity and fine-tunes the pore size of UiO-66-NH2, improving the affinity towards CO2 and thus promoting the permea-selectivity for CO2, which is further verified by GCMC and EMD methods. This work is expected to offer a facile composite layer manufacturing method for MMCMs with high VOC adsorption and CO2 permea-selectivity.

2.
Angew Chem Int Ed Engl ; : e202416921, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39347914

RESUMO

Mineralization of emerging contaminants by using advanced oxidation processes (AOPs) is a desirable option to ensure water safety, but still challenged by the excessive chemical and/or energy input. Here, we conceptually proposed the tandem reaction system (TRS) of different reactive oxygen species (ROS) based on structure adaption of target contaminants. To construct a model TRS, we first realized highly selective generation of three classical ROS (1O2, HO• and SO4•-) by peroxymonosulfate activation in an electrochemical Fenton-like system, where three replaceable Fe-centered cathodes were rationally designed as electronic mediator. The 1O2+SO4•--TRS exhibited nearly 100% mineralization of sulfamethoxazole (SMX), whereas only 34.2%, 56.2% and 60.8% for each of the single 1O2/HO•/SO4•--AOP systems. Mechanism exploration of SMX degradation in TRS evidenced that the initial reaction with 1O2 selectively destructed the sulfonamide bridge of SMX to form p-aminobenzenesulfonic acid, which will be vulnerable to sequent SO4•- attack to facilitate mineralization. Successful extendibility of 1O2+SO4•--TRS to other sulfonamide antibiotics and 1O2+HO•-TRS to phenolic and arylcarboxylic compounds, as well as the demonstration of 1O2+SO4•--TRS in treatment of three actual pharmaceutical wastewaters strongly support that TRS is a powerful and sustainable strategy to enhance the mineralization of emerging contaminants in water.

3.
Angew Chem Int Ed Engl ; : e202414481, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227999

RESUMO

Electro-oxidation (EO) technology demonstrates significant potential in wastewater treatment. However, the high energy consumption has become a pivotal constraint hindering its large-scale implementation. Herein, we design an EO and 4-electron oxygen reduction reaction coupled system (EO-4eORR) to replace the traditional EO and hydrogen evolution reaction (HER) coupled system (EO-HER). The theoretical cathodic potential of the electrolytic reactor is tuned from 0 V (vs. RHE) in HER to 1.23 V (vs. RHE) in 4eORR, which greatly decreases the required operation voltage of the reactor. Moreover, we demonstrate that convection can improve the mass transfer of oxygen and organic pollutants in the reaction system, leading to low cathodic polarization and high pollutant removal rate. Compared with traditional EO-HER system, the energy consumption of the EO-4eORR system under air aeration for 95 % total organic carbon (TOC) removal is greatly decreased to 2.61 kWh/kgTOC (only consider the electrolyzer energy consumption), which is superior to previously reported EO-based water treatment systems. The reported results in this study offer a new technical mode for development of highly efficient and sustainable EO-based treatment systems to remove organic pollutants in waste water.

4.
Angew Chem Int Ed Engl ; 63(10): e202317214, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38263618

RESUMO

Photocatalytic H2 O2 generation system based on polymer catalyst receives increasing attention in recent years; however, the insufficient charge separation efficiency and low oxygen adsorption/activation capacity severely limit their potential application. In this study, a sulfur (C=S) functionalized polymer catalyst is reported through a green water-mediated and catalyst-free multi-component reactions (MCRs) route. The sulfur functional group endows the polymer with a suitable energy band and facilitates the separation of photogenerated electron-hole pair. The reported polymer achieves a high H2 O2 production efficiency (3132 µmol g-1 h-1 ) in pure water without oxygen aeration. To demonstrate their potential in in situ wastewater treatment, a panel reactor system (20×20 cm) is constructed for large-scale production of H2 O2 , which realizes continuous degradation of emerging pollutants including antibiotics and bisphenol A under natural sunlight irradiation condition. The H2 O2 utilization efficiency of the photo-self-Fenton system using in situ generated H2 O2 is found 7.9 times higher than that of the traditional photo-Fenton system. This study offers new insights in green synthesis and design of functional polymer photocatalyst, and demonstrates the feasibility of panel reactor system for large-scale continuous H2 O2 photocatalytic production and water treatment.

5.
Anal Chem ; 95(49): 18065-18074, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38019807

RESUMO

Two-dimensional violet phosphorus (VP) has emerged as a new sensing material in various sensing applications due to its unique electrical properties and high stability among allotropes of phosphorus. Currently, the research of the VP-based analysis method is at the early stage. In this work, a VP nanosheet-based field-effect transistor (FET) sensor is reported for the detection of NO2 and N2O gases with extraordinary sensing performance. This sensor can achieve excellent sensitivity of up to ∼50% current change/ppm and a low detection limit of 5.9 ppb and enables the NO2 analysis in various mixed gases. Moreover, this sensor can effectively distinguish between NO2 and N2O gases, which is a big challenge for current FET or chemiresistor gas sensors. The different sensing behaviors of the VP sensor to NO2 and N2O gases have been investigated, and the mechanism study shows that the adsorption energy, bond length of the gas molecule on the VP surface, and the decomposition of N2O led to the differential responses. This work is one of the pioneer studies of VP gas sensors and presents a new sensing method for the discriminative analysis of NO2 and N2O for greenhouse gas emission monitoring and air quality control.

6.
Anal Chem ; 95(4): 2436-2444, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36650048

RESUMO

Disinfection byproducts (DBPs), as an emerging water pollutant, present increasing concern and risk in public health and water safety. Due to their low concentration levels and inherent similarity in molecular structures, sensitive and accurate determination of DBPs is still a challenge especially for onsite or online detection. Herein, a self-regulated fluorescent probe based on the Ag nanoprism-modified lanthanide metal-organic framework (AgNPR@EuMOF) is designed for trichloroacetic acid (TCAA) detection. The EuMOF is constructed with Eu as the metal node and 5-boronoisophthalic acid as the ligand. By introducing sulfhydryl groups into EuMOF, AgNPR can be anchored on the EuMOF surface through Ag-S bonds, enabling the synthesis of stable AgNPR@EuMOF composites. During the sensing process, the triangle AgNPR will react with the organic halogen molecule, accomplished with the blue shift of surface plasmon resonance absorption peak and the significant change in the fluorescence of EuMOF. This probe can detect TCAA in a wide concentration range (0.1-40 µM) with high sensitivity and specificity. The density functional theory calculation on binding energies between DBPs and AgNPR suggests that TCAA has the largest interaction ability with AgNPR than other DBPs. Moreover, the detection of TCAA in real tap water and swimming pool water is also demonstrated with high accuracy. The reported AgNPR@EuMOF represents one of the pioneer fluorescence probes in DBP detection, which holds great promise for onsite or online analysis of trace DBPs in water.

7.
Small ; 19(46): e2303796, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37442785

RESUMO

Photocatalytic production of H2 O2 has drawn significant attention in recent years, but the yield rate of current photocatalytic systems is still unsatisfactory. Moreover, the presence of various components in actual water bodies will consume the photogenerated charges and deactivate the catalyst, severely limiting the real applications of photocatalytic H2 O2 production. Herein, a cyano-modified polymer photocatalyst is synthesized by Knoevenagel condensation with subsequent thermal polymerization. The introduction of cyano group and sulfer (S), oxygen (O) elements modulates the microstructure and energy band of the polymer catalyst, and the cyano group sites can effectively adsorb and activate O2 , realizing the generation of H2 O2 in the two-step single-electron oxygen reduction process. The reported system achieves high H2 O2 generation rate up to 1119.2 µmol g-1 h-1 in various water bodies including tap water, river water, seawater, and secondary effluent. This simple and readily available catalyst demonstrates good anti-interference performance and pH adaptability in photocatalytic H2 O2 production in actual water bodies, and its photodegradation and sterilization applications are also demonstrated. This study offers new insights in developing polymer catalysts for efficient photocatalytic production of H2 O2 in various water bodies for practical application.

8.
Environ Sci Technol ; 57(36): 13710-13720, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37639499

RESUMO

The efficiency of persulfate-assisted advanced oxidation processes (PS-AOPs) in degrading organic pollutants is affected by the electron-donating capability of organic substances present in the water source. In this study, we systematically investigate the electron-donating capacity (EDC) difference between groundwater and surface water and demonstrate the dependence of removal efficiency on the EDC of target water by PS-AOPs with carbon nanotubes (CNTs) as a catalyst. Laboratory analyses and field experiments reveal that the CNT/PS system exhibits higher performance in organic pollutant removal in groundwater with a high concentration of phenols, compared to surface water, which is rich in quinones. We attribute this disparity to the selective electron transfer pathway induced by potential difference between PS-CNT and organic substance-CNT intermediates, which preferentially degrade organic substances with stronger electron-donating capability. This study provides valuable insights into the inherent selective removal mechanism and application scenarios of electron transfer process-dominated PS-AOPs for water treatment based on the electron-donating capacity of organic pollutants.


Assuntos
Poluentes Ambientais , Água Subterrânea , Nanotubos de Carbono , Elétrons , Oxirredução
9.
Sensors (Basel) ; 23(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36679368

RESUMO

During these years, the 3D node coverage of heterogeneous wireless sensor networks that are closer to the actual application environment has become a strong focus of research. However, the direct application of traditional two-dimensional planar coverage methods to three-dimensional space suffers from high application complexity, a low coverage rate, and a short life cycle. Most methods ignore the network life cycle when considering coverage. The network coverage and life cycle determine the quality of service (QoS) in heterogeneous wireless sensor networks. Thus, energy-efficient coverage enhancement is a significantly pivotal and challenging task. To solve the above task, an energy-efficient coverage enhancement method, VKECE-3D, based on 3D-Voronoi partitioning and the K-means algorithm is proposed. The quantity of active nodes is kept to a minimum while guaranteeing coverage. Firstly, based on node deployment at random, the nodes are deployed twice using a highly destructive polynomial mutation strategy to improve the uniformity of the nodes. Secondly, the optimal perceptual radius is calculated using the K-means algorithm and 3D-Voronoi partitioning to enhance the network coverage quality. Finally, a multi-hop communication and polling working mechanism are proposed to lower the nodes' energy consumption and lengthen the network's lifetime. Its simulation findings demonstrate that compared to other energy-efficient coverage enhancement solutions, VKECE-3D improves network coverage and greatly lengthens the network's lifetime.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Simulação por Computador , Fenômenos Físicos , Algoritmos
10.
Environ Sci Technol ; 56(9): 5753-5762, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35420409

RESUMO

We report an electrolysis system using NiFe layered double hydroxide/CoMoO4/nickel foam (NFLDH/CMO/NF) as the anode and CMO/NF as the cathode for simultaneous phenol electro-oxidation and water electrolysis. This system shows high performance for both phenol degradation and hydrogen evolution. We demonstrate that the degradation rate of phenol on the active anode is governed by the mass transfer rate at a low phenol concentration (0.5-2 mM) and by the electro-oxidation rate at a high phenol concentration (5 mM). The anodic oxygen evolution reaction (OER) can promote the phenol degradation through enhanced mass transfer efficiency. More importantly, the common deactivation issue of phenol electro-oxidation on the inert anode can be eliminated by the high OER activity of the active anode. The constructed full electrolytic cell only needs a low potential of 1.498 V to achieve 10 mA/cm2 for water electrolysis. The reported promotion effect of phenol degradation by OER as well as the improved anode resistance to deactivation offer new insights into efficient and robust waste-to-resource electrolysis system for water treatment.


Assuntos
Fenol , Poluentes Químicos da Água , Eletrodos , Hidrogênio , Oxigênio , Fenóis , Titânio , Águas Residuárias
11.
Environ Sci Technol ; 56(4): 2665-2676, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35077141

RESUMO

Selective removal of organic pollutants by advanced oxidation methods has been receiving increasing attention for environmental remediation. In this study, a novel catalyst, which can selectively oxidize phenolic compounds (PCs) based on their hydrophobicity, composed of metal-organic-framework-derived Fe/Fe3O4 and three-dimensional reduced graphene oxide (rGOF) is designed for peroxydisulfate (PDS) activation. This heterogeneous PDS activation system can completely degrade hydrophobic PCs within 30 min. By investigating the hydrophobic properties of eight representative PCs, a positive correlation between the hydrophobicity of PC and the reaction kinetics is reported for the first time. The selective removal stems from the strong interaction between highly hydrophobic PCs and the catalyst. Moreover, the mechanism investigation shows that the degradation reaction is triggered by interface reactive oxygen species (ROS). Our study reveals that the selective degradation of organic pollutants by PDS activation depends on the hydrophilic and hydrophobic properties of the pollutant and catalyst. The reported results provide new insights into a highly selective and efficient PDS activation system for organic pollutant removal.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Catálise , Interações Hidrofóbicas e Hidrofílicas , Oxirredução , Fenóis , Espécies Reativas de Oxigênio , Poluentes Químicos da Água/análise
12.
Exp Lung Res ; 48(9-10): 275-290, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36346360

RESUMO

Background: Blast lung injury (BLI) is the most common fatal blast injury induced by overpressure wave in the events of terrorist attack, gas and underground explosion. Our previous work revealed the characteristics of inflammationrelated key proteins involved in BLI, including those regulating inflammatory response, leukocyte transendothelial migration, phagocytosis, and immune process. However, the molecular characteristics of oxidative-related proteins in BLI ar still lacking. Methods: In this study, protein expression profiling of the blast lungs obtained by tandem mass tag (TMT) spectrometry quantitative proteomics were re-analyzed to identify the characteristics of oxidative-related key proteins. Forty-eight male C57BL/6 mice were randomly divided into six groups: control, 12 h, 24 h, 48 h, 72 h and 1 w after blast exposure. The differential protein expression was identified by bioinformatics analysis and verified by western blotting. Results: The results demonstrated that thoracic blast exposure induced reactive oxygen species generation and lipid peroxidation in the lungs. Analysis of global proteins and oxidative-related proteomes showed that 62, 59, 73, 69, 27 proteins (accounted for 204 distinct proteins) were identified to be associated with oxidative stress at 12 h, 24 h, 48 h, 72 h, and 1 week after blast exposure, respectively. These 204 distinct proteins were mainly enriched in response to oxidative stress, oxidation-reduction process and lipid metabolic process. We also validated these results by western blotting. Conclusions: These findings provided new perspectives on blast-induced oxidative injury in lung, which may potentially benefit the development of future treatment of BLI.


Assuntos
Traumatismos por Explosões , Lesão Pulmonar , Animais , Camundongos , Masculino , Lesão Pulmonar/metabolismo , Proteômica , Traumatismos por Explosões/metabolismo , Camundongos Endogâmicos C57BL , Estresse Oxidativo/fisiologia , Oxirredução , Pulmão/metabolismo , Lipídeos
13.
J Mater Sci Mater Med ; 33(2): 12, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35050422

RESUMO

Because of stem cells are limited by the low efficiency of their cell homing and survival in vivo, cell delivery systems and scaffolds have attracted a great deal of attention for stem cells' successful clinical practice. ß-chitin nanofibers (ß-ChNF) were prepared from squid pens in this study. Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy proved that ß-ChNFs with the diameter of 5 to 10 nm were prepared. ß-ChNF dispersion became gelled upon the addition of cell culture medium. Cell culture experiments showed that ß-ChNFs exhibited negligible cytotoxicity towards ADSCs and L929 cells, and it was found that more exosomes were secreted by the globular ADSCs grown in the ß-ChNF hydrogel. The vivo experiments of rats showed that the ADSCs-loaded ß-ChNF hydrogel could directly cover the wound surface and significantly accelerate the wound healing and promote the generation of epithelization, granulation tissue and collagen. In addition, the ADSCs-loaded ß-ChNF hydrogel clearly regulated the expressions of VEGFR, α-SMA, collagen I and collagen III. Finally, we showed that ADSCs-loaded ß-ChNF hydrogel activated the TGFß/smad signaling. The neutralization of TGFß markedly reduced Smad phosphorylation and the expressions of TIMP1, VEGFR and α-SMA. Taken together, these findings suggest that ADSCs-loaded ß-ChNF hydrogel promises for treating wounds that are challenge to heal via conventional methods. Graphical abstract.


Assuntos
Adipócitos , Quitina/química , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/fisiologia , Nanofibras/química , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis , Hidrogéis/química , Ratos , Ratos Sprague-Dawley , Alicerces Teciduais
14.
Anal Chem ; 93(22): 8010-8018, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34019758

RESUMO

Silver (Ag) is a widely used heavy metal, and its oxidation state (Ag+) causes serious harm to organisms after bioaccumulation and biomagnification, posing urgent demand for the rapid, efficient, and simply operated Ag+ detection techniques. In this work, a fast, portable, and label-free Ag+ detection sensor based on a Ti3C2Tx MXene field-effect transistor (FET) is reported. The Ti3C2Tx MXene works as the sensing element in the FET sensor, which shows excellent sensing performance, i.e., fast response (few seconds) and good sensitivity and selectivity to Ag+ without any detection label or probe. Utilizing the visual photograph, transmission electron microscopy image, and Ag elemental mapping analysis, the sensing mechanism of the label-free Ti3C2Tx MXene FET sensor is demonstrated to be the in situ reduction of Ag+ and the formation of Ag nanoparticles (AgNPs). Moreover, Ag+ detection in real samples shows that the proposed FET devices have satisfactory sensing capability for Ag+ in tap water and river water. This study puts forward a novel FET strategy for Ag+ detection in aqueous systems, which is of essential and inspiring meaning for motivating the potential applications of MXene-based sensor devices in analytical applications and the realization of on-site environmental monitoring.


Assuntos
Nanopartículas Metálicas , Prata , Titânio , Água
15.
J Oral Pathol Med ; 49(4): 311-319, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32145110

RESUMO

OBJECTIVE: This meta-analysis was performed to systematically evaluate the efficacy of hyaluronidase combined with corticosteroids compared with other drugs in improving maximum mouth opening and alleviating the burning sensation in patients with oral submucous fibrosis (OSF). METHODS: PubMed, Embase, Web of Science and the Cochrane Library were searched. RevMan 5.3 software was used for the meta-analysis. RESULTS: Six studies involving 244 patients with OSF were analysed. No significant difference in improvement of maximum mouth opening was found between the hyaluronidase and control groups (lycopene, pentoxifylline, aloe vera, dexamethasone, Turmix [curcumin + piperine] and isoxsuprine) at 1 month (mean difference [MD]: 0.32, 95% confidence interval [CI]: -0.92-1.56, P = .61, I2  = 57%), 2 months (MD: 0.49, 95% CI: -0.14-1.12, P = .12, I2  = 41%) or 3 months (MD: 0.40, 95% CI: -1.08-1.87, P = .60, I2  = 92%). Additionally, no statistically significant difference was found in alleviation of the burning sensation between the two groups at 1 month (MD: 0.54, 95% CI: -0.62-1.71, P = .36, I2  = 0%), 2 months (MD: 0.53, 95% CI: -0.85-1.91, P = .45, I2  = 0%) or 3 months (MD: 0.64, 95% CI: -1.07 to 2.35, P = .46, I2  = 0%). CONCLUSIONS: According to this meta-analysis, weak evidence indicates that hyaluronidase combined with corticosteroids has no additional clinical benefit over control drugs (lycopene, pentoxifylline, aloe vera, dexamethasone, Turmix and isoxsuprine) in improving maximum mouth opening and alleviating the burning sensation in patients with OSF. Therefore, more high-quality, multi-centre randomized controlled trials with larger samples are needed to further assess the efficacy of hyaluronidase combined with corticosteroids in the treatment of OSF.


Assuntos
Corticosteroides/uso terapêutico , Hialuronoglucosaminidase/uso terapêutico , Fibrose Oral Submucosa/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Environ Res ; 188: 109764, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32531522

RESUMO

The ever-increasing production of waste activated sludge (WAS) has become a widespread problem to sewage treatment plants around the world. Among the multitudinous sludge treatment methods, chemical oxidation is considered as an excellent technology with both high efficiency and low investment cost. As an eco-friendly oxidant, potassium ferrate (PF) has attracted great attention in sludge treatment over the past decade. The applications of PF have demonstrated advantages in: (1) sludge dewatering; (2) minimization; (3) anaerobic fermentation; (4) removal of pollutants. This review summarizes recent work on the effects of PF on these four aspects of facilitating sludge disposal. Meanwhile, the underlying mechanisms for the diverse applications of PF on sludge treatment are analyzed. Furthermore, the shortages and knowledge gaps on current PF oxidizing methods are discussed, and directions for further research to simultaneously enhance treatment efficiency and reduce processing cost are suggested as well.


Assuntos
Compostos de Ferro , Esgotos , Oxidantes , Compostos de Potássio , Eliminação de Resíduos Líquidos
17.
Chem Soc Rev ; 46(22): 6872-6904, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-28933459

RESUMO

Meeting the increasing demand for sensors with high sensitivity, high selectivity, and rapid detection presents many challenges. In the last decade, electronic sensors based on field-effect transistors (FETs) have been widely studied due to their high sensitivity, rapid detection, and simple test procedure. Among these sensors, two-dimensional (2D) nanomaterial-based FET sensors have been demonstrated with tremendous potential for the detection of a wide range of analytes which is attributed to the unique structural and electronic properties of 2D nanomaterials. This comprehensive review discusses the recent progress in graphene-, 2D transition metal dichalcogenide-, and 2D black phosphorus-based FET sensors, with an emphasis on rapid and low-concentration detection of gases, biomolecules, and water contaminants.


Assuntos
Técnicas Biossensoriais/instrumentação , Desenho de Equipamento/instrumentação , Grafite/química , Nanoestruturas/química , Transistores Eletrônicos , Condutometria/métodos , Humanos , Nanotecnologia/métodos , Fenômenos Físicos
18.
Chem Soc Rev ; 44(8): 2108-21, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25711336

RESUMO

Graphene nanosheets arranged perpendicularly to the substrate surface, i.e., vertically-oriented graphenes (VGs), have many unique morphological and structural features that can lead to exciting properties. Plasma-enhanced chemical vapor deposition enables the growth of VGs on various substrates using gas, liquid, or solid precursors. Compared with conventional randomly-oriented graphenes, VGs' vertical orientation on the substrate, non-agglomerated morphology, controlled inter-sheet connectivity, as well as sharp and exposed edges make them very promising for a variety of applications. The focus of this tutorial review is on plasma-enabled simple yet efficient synthesis of VGs and their properties that lead to emerging energy and environmental applications, ranging from energy storage, energy conversion, sensing, to green corona discharges for pollution control.


Assuntos
Fontes Geradoras de Energia , Meio Ambiente , Grafite/química , Nanotecnologia/métodos , Humanos
19.
Small ; 11(40): 5336-59, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26315216

RESUMO

Water contaminants, e.g., inorganic chemicals and microorganisms, are critical metrics for water quality monitoring and have significant impacts on human health and plants/organisms living in water. The scope and focus of this review is nanomaterial-based optical, electronic, and electrochemical sensors for rapid detection of water contaminants, e.g., heavy metals, anions, and bacteria. These contaminants are commonly found in different water systems. The importance of water quality monitoring and control demands significant advancement in the detection of contaminants in water because current sensing technologies for water contaminants have limitations. The advantages of nanomaterial-based sensing technologies are highlighted and recent progress on nanomaterial-based sensors for rapid water contaminant detection is discussed. An outlook for future research into this rapidly growing field is also provided.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Nanoestruturas/química
20.
Small ; 11(4): 414-9, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25208086

RESUMO

By increasing the density of exposed active edges, the perpendicularly oriented structure of MoSe2 nanosheets facilitates ion/electrolyte transport at the electrode interface and minimizes the restacking of nanosheets, while the graphene improves the electrical contact between the catalyst and the electrode. This makes the MoSe2 /graphene hybrid perfect as a catalyst in the hydrogen evolution reaction (HER). It shows a greatly improved catalytic activity compared with bare MoSe2 nanosheets.

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