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1.
Angew Chem Int Ed Engl ; 63(11): e202319741, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38196288

RESUMO

Spatially confined photocatalysis has emerged as a viable strategy for the intensification of various redox reactions, but the influence of confined structure on reaction behavior is always overlooked in gas-solid reactions. Herein, we report a nanomembrane with confining Cs3 Bi2 Br9 nanocrystals inside vertical channels of porous insulated silica thin sheets (CBB@SBA(⊥)) for photocatalytic nitric oxide (NO) abatement. The ordered one-dimensional (1D) pore channels with mere 70 nm channel length provide a highly accessible confined space for catalytic reactions. A record-breaking NO conversion efficiency of 98.2 % under a weight hourly space velocity (WHSV) of 3.0×106  mL g-1 h-1 , as well as exceptionally high stability over 14 h and durability over a wide humidity range (RH=15-90 %) was realized over SBA(⊥) confined Cs3 Bi2 Br9 , well beyond its nonconfined analogue and the Cs3 Bi2 Br9 confine in Santa Barbara Amorphous (SBA-15). Mechanism studies suggested that the insulated pore channels of SBA(⊥) in CBB@SBA(⊥) endow concentrated electron field and enhanced mass transfer that render high exposure of reactive species and lower reaction barrier needs for ⋅O2 - formation and NO oxidation, as well as prevents structural degradation of Cs3 Bi2 Br9 . This work expands an innovative strategy for designing efficient photocatalysts for air pollution remediation.

2.
Environ Sci Technol ; 55(24): 16723-16734, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34882404

RESUMO

Constructing catalysts with electronic metal-support interaction (EMSI) is promising for catalytic reactions. Herein, graphene-supported positively charged (Pt2+/Pt4+) atomically dispersed Pt catalysts (AD-Pt-G) with PtxC3 (x = 1, 2, and 4)-based EMSI coordination structures are achieved for boosting the catalytic ozonation for odorous CH3SH removal. A CH3SH removal efficiency of 91.5% can be obtained during catalytic ozonation using optimum 0.5AD-Pt-G within 12 h under a gas hourly space velocity of 60,000 mL h-1 g-1, whereas that of pure graphene is 40.4%. Proton transfer reaction time-of-flight mass spectrometry, in situ diffuse reflectance infrared Fourier transform spectroscopy/Raman, and electron spin resonance verify that the PtxC3 coordination structure with atomic Pt2+ sites on AD-Pt-G can activate O2 to generate peroxide species (*O2) for partial oxidation of CH3SH during the adsorption period and trigger O3 into surface atomic oxygen (*Oad), *O2, and superoxide radicals (·O2-) to accomplish a stable, high-efficiency, and deeper oxidation of CH3SH during the catalytic ozonation stage. Moreover, the results of XPS and DFT calculation imply the occurrence of Pt2+ → Pt4+ → Pt2+ recirculation on PtxC3 for AD-Pt-G to maintain the continuous catalytic ozonation for 12 h, i.e., Pt2+ species devote electrons in 5d-orbitals to activate O3, while Pt4+ species can be reduced back to Pt2+ via capturing electrons from CH3SH. This study can provide novel insights into the development of atomically dispersed Pt catalysts with a strong EMSI effect to realize excellent catalytic ozonation for air purification.


Assuntos
Grafite , Ozônio , Catálise , Oxirredução , Oxigênio
3.
Zhongguo Zhong Yao Za Zhi ; 46(5): 1155-1159, 2021 Mar.
Artigo em Zh | MEDLINE | ID: mdl-33787110

RESUMO

Chemical constituents of water extracts of Asplenium ruprechtii were investigated. Five compounds were isolated by silica gel, Sephadex LH-20 gel column chromatographies and preparative HPLC, and their structures were identified by various spectral analyses as aspleniumside G(1), trans-p-coumaric acid(2), trans-p-coumaric acid 4-O-ß-D-glucoside(3), cis-p-coumaric acid 4-O-ß-D-glucoside(4), and(E)-ferulic acid-4-O-ß-D-glucoside(5). Among them, compound 1 is a new 9,19-cycloartane glycoside.


Assuntos
Glicosídeos , Triterpenos , Cromatografia Líquida de Alta Pressão , Glucosídeos
4.
Environ Sci Technol ; 52(22): 13399-13409, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30362732

RESUMO

In this study, Ag deposited three-dimensional MnO2 porous hollow microspheres (Ag/MnO2 PHMSs) with high dispersion of the atom level Ag species are first prepared by a novel method of redox precipitation. Due to the highly efficient utilization of downsized Ag nanoparticles, the optimal 0.3% Ag/MnO2 PHMSs can completely degrade 70 ppm CH3SH within 600 s, much higher than that of MnO2 PHMSs (79%). Additionally, the catalyst retains long-term stability and can be regenerated to its initial activity through regeneration with ethanol and HCl. The results of characterization of Ag/MnO2 PHMSs and catalytic performance tests clearly demonstrate that the proper amount of Ag incorporation not only facilitates the chemi-adsorption but also induces more formation of vacancy oxygen (Ov) and lattice oxygen (OL) in MnO2 as well as Ag species as activation sites to collectively favor the catalytic ozonation of CH3SH. Ag/MnO2 PHMSs can efficiently transform CH3SH into CH3SAg/CH3S-SCH3 and then oxidize them into SO42- and CO2 as evidenced by in situ diffuse reflectance infrared Fourier transform spectroscopy. Meanwhile, electron paramagnetic resonance and scavenger tests indicate that •OH and 1O2 are the primary reactive species rather than surface atomic oxygen species contributing to CH3SH removal over Ag/MnO2 PHMSs. This work presents an efficient catalyst of single atom Ag incorporated MnO2 PHMSs to control air pollution.


Assuntos
Nanopartículas Metálicas , Ozônio , Compostos de Manganês , Óxidos , Prata , Compostos de Sulfidrila
5.
J BUON ; 23(5): 1331-1336, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30570855

RESUMO

PURPOSE: To investigate the expression of thrombospondin 2 (THBS2) in colorectal cancer (CRC) and its relationship with clinicopathological features and prognosis. METHODS: THBS2 expression was evaluated with tissue microarrays (TMAs) immunohistochemistry (IHC) staining in 100 CRC samples. RESULTS: High THBS2 expression was found in 73 patients (45 male and 28 female). THBS2 expression was significantly correlated to TNM stages (p=4.1×10-5), T classification (p=0.005), lymph node metastasis (p=3×10-4) and AJCC stages (p=0), while no significant association was found in gender, age, distant metastasis or tumor size. In both univariate and multivariate analyses, THBS2 showed statistically prognostic significance [p<0.001, HR (hazard ratio) = 0.237, 95% CI (0.101-0.557) and p<0.001, HR=0.158, 95% CI (0.062-0.401)]. Kaplan-Meier survival analysis further confirmed that THBS2 expression was significantly correlated with clinical outcomes (p<0.001). CONCLUSIONS: All the results indicated THBS2 expression might become a prognostic marker for CRC.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Trombospondinas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/metabolismo , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida
6.
Chemosphere ; 358: 142113, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657694

RESUMO

Ground-level ozone has long posed a substantial menace to human well-being and the ecological milieu. The widely reported manganese-based catalysts for ozone decomposition still facing the persisting issues encompass inefficiency and instability. To surmount these challenges, we developed a mesoporous silica thin films with perpendicular nanochannels (SBA(⊥)) confined Mn3O4 catalyst (Mn3O4@SBA(⊥)). Under a weight hourly space velocity (WHSV) of 500,000 mL g-1 h-1, the Mn3O4@SBA(⊥) catalyst exhibited 100% ozone decomposition efficiency in 5 h and stability across a wide humidity range, which exceed the performance of bulk Mn3O4 and Mn3O4 confine in commonly reported SBA-15. Rapidly decompose 20 ppm O3 to a safety level below 100 µg m-3 in the presence of dust in smog chamber (60 × 60 × 60 cm) was also realized. This prominent catalytic performance can be attributed to the unique confined structure engenders the highly exposed active sites, facilitate the reactant-active sites contact and impeded the water accumulation on the active sites. This work offers new insights into the design of confined structure catalysts for air purification.


Assuntos
Compostos de Manganês , Óxidos , Ozônio , Ozônio/química , Óxidos/química , Catálise , Compostos de Manganês/química , Nanoestruturas/química , Dióxido de Silício/química , Poluentes Atmosféricos/química
7.
Front Neurol ; 15: 1432256, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39314864

RESUMO

Background: Parkinson's disease is characterized by symptoms such as bradykinesia and rigidity, which worsen as the disease progresses, significantly impacting patients' independence and quality of life. This study utilizes a network meta-analysis approach to quantify information gathered from randomized controlled trials (RCTs) regarding motor interventions that effectively improve the motor function of Parkinson's disease patients, aiming to provide evidence for selecting appropriate exercise intervention strategies for patients. Methods: A systematic search strategy for randomized controlled trials (RCTs) restricted to English was constructed based on multiple biomedical databases. Databases searched included PubMed, Embase, Cochrane, Web of Science, CINAHL, CBM, China National Knowledge Infrastructure (CNKI), Wan fang, VIP, etc., with searches conducted from inception to July 9, 2023. Two authors screened all studies, extracted data, and used frequency domain analysis methods. Network meta-analysis was performed using STATA software version 18.0 to compare and rank exercises that could effectively improve the motor function of Parkinson's disease patients (measured by indicators such as MDS-UPDRS-III, TUG, BBS, Mini-BES Test, 6MWT scores). Additionally, a series of analyses and evaluations were conducted, such as assessing the methodological quality of included studies using the Cochrane risk of bias tool. Results: The network meta-analysis included a total of 111 studies involving 5,358 participants, 133 intervention experiments, and 31 intervention measures. Although most exercise interventions showed effectiveness, cumulative ranking curves under the surface (SUCRA) values showed that archery exercise significantly improved patients' MDS-UPDRS-III scores (SUCRA = 95.6%), significantly superior to routine care [standardized mean difference (SMD = 16.92, 95%CI = -28.97, -4.87)]. High-intensity and agility exercise (High strength and agility) referred to as high-intensity exercise or agility training or a combination of both, collectively termed as high-intensity agility training, significantly improved patients' completion time for the time-up-and-go test (SUCRA = 99.7%), (SMD = -7.88, 95%CI = -9.47, -6.28). Dance and Tai Chi exercises significantly improved patients' balance abilities: Mini-Balance Evaluation Systems Test (SUCRA = 77.9%), (SMD = 5.25, 95%CI = -0.42, 10.92) for dance intervention and Berg Balance Scale (SUCRA = 94.7%), (SMD = 11.22, 95%CI = 3.26, 19.18) for Tai Chi intervention. Dance also significantly improved patients' walking ability in the 6-min walk test (SUCRA = 80.5%), (SMD = 71.31, 95%CI = 13.77, 128.84). Conclusion: Compared to other exercises, archery, dance, Tai Chi, and high-intensity agility exercises demonstrate superior efficacy in improving the motor function of Parkinson's disease patients.

8.
J Colloid Interface Sci ; 668: 77-87, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38669998

RESUMO

Transition-metal-atom anchored graphdiynes (TM@GDY, TM = Mn, Fe, Co, Ni and Cu) have already been synthesized and found applications in hydrogen evolution, nitrogen fixation and etc. By means of first-principle predictions and test experiments, we propose here that Fe@GDY and Co@GDY are efficient catalysts for the sustainable conversion of O3 to O2. These two catalysts can spontaneously chemisorb O3 with zero reaction barrier and have low O3 conversion barriers (0.31 eV and 0.19 eV, respectively). The O3 decomposition experiment in a continuous flow membrane reactor and electron paramagnetic resonance results verify that Fe@GDY and Co@GDY are efficient catalysts under humid conditions. Raman spectra prove the formation of the key Fe-O/Co-O and FeOO and CoOO intermediates. The hydrophobic nature of graphdiyne and the strongest chemisorption of O3 among tested ambient gases, make Fe@GDY and Co@GDY ideal catalysts under both dry and humid conditions. These findings would stimulate future explorations on metal anchored GDY-based catalysts for applications of toxic gas decomposition or fixation.

9.
Adv Mater ; 35(13): e2209885, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36644889

RESUMO

Piezoelectric mesocrystals as defective materials have been demonstrated to possess adsorptive and catalytic properties in redox reactions. However, there is still a lack of research on the quantitative relationship between the defect concentration and the piezocatalytic performance in piezoelectric mesocrystals. Herein, twin-hierarchical structure ZnO piezoelectric mesocrystals are taken with different oxygen-vacancies (OVs) concentrations to quantitatively investigate the effect of defect content on the peroxymonosulfate (PMS) piezo-activation in water purification. The ZnO piezoelectric mesocrystal with moderate OVs concentration exhibits a rapid antibiotic ornidazole (ORZ) pollutants degradation rate (0.034 min-1 ) and achieves a high PMS utilization efficiency (0.162) that exceeds the most state-of-the-art catalytic processes, while excessive OVs suppressed the piezocatalytic performance. Through calculations of electron property and reactants affinity, a quantitative relationship between OVs concentration and piezocatalytic properties is established. The ZnO mesocrystal with moderate OVs concentration realized increased electron delocalization, reduced charge transfer barrier, and enhanced reactants affinity, thus accelerating the kinetics of PMS activation. This work provides theoretical guidance for the application of defect engineering in mesocrystal to realize enhanced piezocatalytic performance.

10.
Chemosphere ; 344: 140322, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37775059

RESUMO

The essential factor of catalytic ozonation technology relies on an efficient and stable catalyst. The construction of highly dispersed active sites on heterogeneous catalysts is an ideal strategy to combine the merits of homogeneous and heterogeneous catalysis with high activity and stability. Herein, an iron-containing mesoporous silica material (Fe-SBA15) with sufficient iron site exposure and enhanced intrinsic activity of active sites was employed to activate ozone for bisphenol A (BPA) degradation. Approximately 100% of BPA and 36.6% of total organic carbon (TOC) removal were realized by the Fe-SBA15 catalytic ozonation strategy with a reaction constant of 0.076 min-1, well beyond the performance of FeOx/SBA15 mixture and Fe2O3. Radical quenching experiments and electron paramagnetic resonance (EPR) analysis demonstrated that the hydroxyl radicals (HO•) and superoxide radicals (O2•-) played an important role in the degradation process. The iron sites with recyclable Fe(III)/Fe(II) pairs act as both the electron donors and active sites for catalytic ozonation. The mesoporous framework of SBA15 in Fe-SBA15 stabilizes the iron sites that enhance its stability. With high catalytic performance and high reusability for catalytic ozonation of BPA, the Fe-SBA15 is expected to be a promising catalyst in catalytic ozonation for wastewater treatment.


Assuntos
Ozônio , Poluentes Químicos da Água , Ferro/química , Domínio Catalítico , Catálise , Ozônio/química , Poluentes Químicos da Água/análise
11.
Water Res ; 245: 120612, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37729695

RESUMO

Well water is an important water source in isolated rural areas but easily suffers from microbial contamination. Herein, we anchored periodic Au nanoarrays on mesoporous silica nanodisks (Au-MSN) to fabricate a solar-driven nano-stove for well water disinfection. The solar/Au-MSN process completely inactivated 3.98, 6.55, 7.11 log10 cfu/mL, and 3.37 log10 pfu/mL of Aspergillus niger spores, Escherichia coli, chlorine-resistant Spingopyxis sp. BM1-1, and bacteriophage MS2 within 5 min, respectively. Moreover, the complete inactivation of various microorganisms (even at a viable but nonculturable state) was achieved in the flow-through reactor under natural solar light in real well water matrixes. Thorough characterizations and theoretical simulations verified that the densely anchoring strategy of Au-MSN's nanoarray worked on broadband absorption via the photon confinement effect, and trace amounts of Au can induce strong electromagnetic fields and collective localized heating. The resulting surge of 1O2 and heat synergically destroyed membranes, dysfunction cellular self-defense and metabolic system, induced intracellular oxidative stress, and ultimately inactivated microorganisms. Additionally, the 1O2-dominated oxidation and cell adhesion facilitated the selective disinfection in real well water matrixes. This study provides a cost-effective and practical solution for efficient well water disinfection, which assists isolated rural areas in getting safe drinking water.

12.
Zhonghua Nan Ke Xue ; 17(5): 435-9, 2011 May.
Artigo em Zh | MEDLINE | ID: mdl-21837955

RESUMO

OBJECTIVE: To compare the clinical effects of transurethral detaching resection (TUDRP) and plasmakinetic transurethral resection of the prostate (PKRP) for benign prostatic hyperplasia (BPH). METHODS: We collected by the single blind method the clinical data of 81 cases of BPH treated by PKRP (n=41) and TUDRP (n=40), and compared the two groups of patients in their age, preoperative prostate volume, weight of the resected gland, operation time, intraoperative bleeding, time of postoperative Foley's catheter retention, and pre- and post-operative IPSS. RESULTS: The post-operative IPSS was significantly higher in the PKRP than in the TUDRP group (9.95 +/- 1.54 vs. 8.70 +/- 1.13, t = 0.0029, P = 0.0059). CONCLUSION: TUDPR has a better clinical effect than PKRP in the treatment of BPH.


Assuntos
Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata/métodos , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego
13.
Water Res ; 189: 116627, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33221585

RESUMO

Persulfate-based advanced oxidation processes (PS-based AOPs) under UV, visible, or solar irradiation are being intensively investigated for water treatment. Tremendous advances have been made for enhancing the performance towards the destruction of target pollutants, but a deeper understanding of the role of light in different photo-activated PS-based AOPs is still needed as a basis for improving the efficiency. This paper intends to provide an in-depth review of the underlying photo-activation mechanisms and recent progress in various common photo-activated PS-based AOPs reported over the last decade. Based on a comprehensive survey of previous studies, we categorize these processes according to their reaction mechanisms, including activation by direct UV radiation, processes based on dye-photosensitization, activation through ligand-to-metal charge transfer (LMCT), and photocatalytic processes. Moreover, the improvement in performance of contaminant degradation in these processes compared with those in the absence of light are summarized. Finally, we conclude this review by proposing critical challenges and future perspectives for developing efficient photo-activated PS-based AOPs toward improvement in water treatment and remediation.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Oxirredução , Raios Ultravioleta , Poluentes Químicos da Água/análise
14.
Int J Mol Med ; 48(3)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34278451

RESUMO

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the Transwell cell migration data shown in Figs. 2D and 4C were strikingly similar to data appearing in different form in other articles by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to International Journal of Molecular Medicine, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive any reply. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in International Journal of Molecular Medicine 38: 1587­1595, 2016; DOI: 10.3892/ijmm.2016.2754].

15.
Chemosphere ; 258: 127339, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554010

RESUMO

In this paper, a two dimensional/two dimensional (2D/2D) heterostructure of Ti3C2/g-C3N4 (T/CN) was constructed and used to activate peroxymonosulfate (PMS) for the degradation of diclofenac (DCF) in water in the presence of light illumination. Compared with single photocatalytic process by T/CN (0.040/min) and with pure g-C3N4 nanosheets in PMS system (0.071/min), 5.0 and 3.0 times enhanced activities were achieved in the T/CN-PMS system at optimum Ti3C2 (1.0 wt%) loading under light illumination (0.21/min). Moreover, the decomposing processes of DCF in T/CN-PMS system were applicable in a wide initial pH range (3∼14), therefore, overcoming the limitation of pH dependence in traditional PMS system. Based on the synergistic effect of photocatalysis and PMS oxidation processes, the 1O2 was generated as primary reactive species for the removal of DCF in T/CN-PMS system. The DCF degradation mechanism was further proposed through the results of liquid chromatography-mass spectrometry (LC-MS) and density functional theory (DFT) calculations.


Assuntos
Diclofenaco/química , Grafite/química , Compostos de Nitrogênio/química , Peróxidos/química , Titânio/química , Catálise , Estrutura Molecular , Oxirredução , Peróxidos/efeitos da radiação
16.
ACS Appl Mater Interfaces ; 12(6): 7459-7465, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31961650

RESUMO

We report on our use of a thin-layered vertical mesoporous silica thin film (MSTF) with tunable pore size overlaid on an anodic aluminum oxide (AAO) membrane for advancing water purification. The features of ultrathin thickness (about 20 nm), a uniform vertical pore orientation, low tortuosity, high porosity, and a hydrophilic surface endow the MSTF membranes with ultrahigh water permeability compared with that of state-of-the-art membranes. The modified E-MSTF membrane with a small pore diameter of 2.1 ± 0.1 nm demonstrates superior nanofiltration performance for dye molecules with a cutoff of 520 Da and ultrahigh water permeability of 310 ± 8 L m-2 h-1 bar-1. Furthermore, the precise molecular sieving of dye/salt mixtures was realized with outstanding salt permeation (97.5% NaCl, 96.0% Na2SO4) and a high retention of dye (99.0%). The water permeance and selectivity of the modified E-MSTF membrane are higher than that of reported membranes with similar dye rejections. This work opens up new avenues for constructing tailor-made membranes with tunable pore size and remarkable separation performance.

17.
Nanomaterials (Basel) ; 8(12)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30486493

RESUMO

TiO2 is one of the most attractive semiconductors for use as a photoanode for photoelectrochemical (PEC) water oxidation. However, the large-scale application of TiO2 photoanodes is restricted due to a short hole diffusion length and low electron mobility, which can be addressed by metal doping and surface decorating. In this paper we report the successful synthesis of hierarchical Ta doped TiO2 nanorod arrays, with nanoparticles on the top (Ta:TiO2), on F-doped tin oxide (FTO) glass by a hydrothermal method, and its application as photoanodes for photoelectrochemical water oxidation. It has been found that the incorporation of Ta5+ in the TiO2 lattice can decrease the diameter of surface TiO2 nanoparticles. Ta:TiO2-140, obtained with a moderate Ta concentration, yields a photocurrent of ∼1.36 mA cm-2 at 1.23 V vs. a reversible hydrogen electrode (RHE) under FTO side illumination. The large photocurrent is attributed to the large interface area of the surface TiO2 nanoparticles and the good electron conductivity due to Ta doping. Besides, the electron trap-free model illustrates that Ta:TiO2 affords higher transport speed and lower electron resistance when under FTO side illumination.

18.
J Hazard Mater ; 344: 33-41, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29031092

RESUMO

Hierarchical porous sludge-derived activated carbon coated on macroporous silicon carbide (SiC) foams substrate has been facilely fabricated via a simple one-step strategy by utilizing sludge as carbon source, and jointly using zinc chloride and hexadecanol as pore forming agents. The sludge-derived carbon has been confirmed to be hierarchical macro-meso-microporous structure based on detailed characterization by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra and nitrogen adsorption-desorption measurement. The adsorption tests showed that the hierarchical porous sludge-derived activated carbon fabricated by one-step pore-forming (zinc chloride and hexadecanol microemulsion mixture) possesses excellent adsorption capacity (259.9mgg-1, breakthrough time reach 90min and saturation end-time up to 140min) of methyl mercaptan (CH3SH). The excellent adsorption performance can be attributed to the macroporous SiC foam skeleton and the mesopores channel formed by nonionic surfactant hexadecanol micelles, as well as the micropores activated by ZnCl2 as odor capture sites. The proposed pore-forming strategy paves an avenue for the sludge disposal and even the development of bio-derived materials.


Assuntos
Compostos Inorgânicos de Carbono/química , Carbono/química , Odorantes , Esgotos/química , Compostos de Silício/química , Compostos de Sulfidrila/química , Adsorção , Cloretos/química , Porosidade , Compostos de Zinco/química
19.
Nanoscale ; 10(41): 19367-19374, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30307005

RESUMO

Owing to its excellent chemical stability and low cost, titanium dioxide (TiO2) has been widely studied as a photoanode for photoelectrochemical (PEC) water splitting. However, TiO2's practical applications in solar energy-to-synthetic fuel conversion processes have been constrained by its inherently poor ability to transport photogenerated electrons and holes. In this paper, we report Ta-doped porous TiO2 nanorod arrays on Ta foil (Ta-PTNA) that do not possess this issue and that can thus efficiently photoelectrocatalyze water oxidation, helping the production of H2 (a clean fuel) from water at the expense of solar light. The materials are synthesized by a new, facile synthetic approach involving the hydrothermal treatment of a TiO2 precursor with Ta foil, without seeds and templates, and followed by calcination of the product. Besides serving as a source of Ta dopant atoms, Ta foil is found to play a vital role in the formation of nanopores in the materials. The material obtained with hydrothermal treatment at 180 °C for 10 h (Ta-PTNA-10), in particular, affords very large photocurrent density and very high photoconversion efficiency (0.32% at 0.79 V vs. RHE, which is better than those of many previously reported photocatalysts and ∼4 times larger than that of undoped TiO2 nanorod arrays). Ta-PTNAs' remarkable PEC catalytic performance is found to be due to their nanoporous structure and high electronic conductivity.

20.
J Hazard Mater ; 358: 136-144, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29990800

RESUMO

The poor reusability of catalysts and secondary pollution are critical issues for sulfur-containing volatile organic compounds (S-VOCs) removal. In this paper, a three-dimensional (3D) hierarchical porous sludge-derived carbon supported on silicon carbide foams (SiC) has been fabricated for deep decomposition of S-VOCs under ambient conditions. The sludge-derived Fenton-like catalyst has been confirmed to be hierarchical 3D porous structure based on detailed characterization by scanning electron microscopy (SEM), X-ray diffraction (XRD), Nitrogen adsorption-desorption measurements and Raman spectroscopy. Significantly, the catalyst after KOH activation (SCFeK-SiC) shows excellent catalytic decomposition of methyl mercaptan (CH3SH) with almost complete CH3SH oxidation into sulfate using hydrogen peroxide as an oxidant under ambient conditions. This catalyst also possesses relative low iron dissolution and excellent cycling performance. The efficient catalytic ability of SCFeK-SiC can be attributed to SiC foam functioned as a stable 3D macroporous skeleton, in which the porous sludge-derived carbon immobilizes the active iron species and promotes the efficient capture of gaseous CH3SH, thus facilitating the decomposition of CH3SH by generating reactive species, specifically ·OH. The reaction mechanism was systematically investigated. Herein, the design of the porous sludge-derived carbonaceous Fenton-like catalyst paves an avenue for efficient VOCs treatment and rational sludge disposal.

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