Electrospun tailored ZnO nanostructures – role of chloride ions

Zinc oxide (ZnO) and aluminum (Al) doped ZnO nanostructures with and without surfactant have been successfully prepared via sol-gel route. The effect of the surfactant glyoxalic acid and various concentration of Al on the structural property of ZnO was analyzed by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR). The morphology of the samples was recorded using field emission scanning electron microscopy. The uniform distribution of ZnO nanostructures with hexagonal facets is facilitated by the surfactant and the grain growth is further inhibited by the increase in concentration of Al. The ethanol (0–300[Formula: see text]ppm) sensing characteristics of the as-prepared samples were systematically investigated at room temperature. Surfactant-assisted ZnO/Al:ZnO nanostructures show higher sensitivity of 94% at room temperature than ZnO/Al:ZnO nanostructures without surfactant. Faster response at 68[Formula: see text]s and recovery at 50[Formula: see text]s is also achieved by the samples. The surfactant-assisted ZnO nanostructures exhibit sharp selective detection towards ethanol when compared to the samples without surfactant. The enhanced ethanol sensing property may be ascribed to the larger surface area which is due to uniform and smaller crystallite size of the surfactant-assisted sample.

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Role of Additives in Tin Oxide-Based Sensors for Alcohols

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.277-279.403 ◽

2005 ◽

Vol 277-279 ◽

pp. 403-409 ◽

Cited By ~ 2

Author(s):

Hae Won Cheong ◽

Hee Sook Park Kim ◽

Ki Hyun Yoon

Keyword(s):

Tin Oxide ◽

Bond Cleavage ◽

Cleavage Product ◽

Oxidation Products ◽

Oxygen Species ◽

Enhanced Sensitivity ◽

Adsorbed Oxygen Species ◽

Ethanol Sensing ◽

Sensing Characteristics

Using gas chromatographic analyses, the effects of additives (PdCl2, Al2O3, or La2O3) on the alcohol sensing properties of SnO2-based sensors were investigated with respect to the distribution and the reaction steps of the products formed from the reactions of alcohols over the SnO2-based powder. Ethanol was catalytically oxidized with the SnO2-based powders. With the PdCl2-doped SnO2, the C–C bond cleavage product, methane, was produced. This seems to be related with the significant promotional role of PdCl2-doping in ethanol sensing especially at temperatures below 300 oC. For the La2O3-doped SnO2, relatively large amounts of CO and CO2 were produced, resulting in an enhanced sensitivity. On the other hand, for the Al2O3-doped SnO2, selective dehydration, which consumes smaller amounts of the adsorbed oxygen species (O- ads), seems to degrade the sensitivity. When exposed to methanol, the SnO2-based sensors showed oxidation products consisting of CO, CO2 and H2O and sensing characteristics similar to those observed with ethanol.

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Optical and electrical correlation effects in ZnO nanostructures: Role of pulsed laser annealing

Optical Materials ◽

10.1016/j.optmat.2021.111028 ◽

2021 ◽

Vol 115 ◽

pp. 111028

Author(s):

Hayder J. Al-Asedy ◽

Shuruq A. Al-khafaji ◽

S.K. Ghoshal

Keyword(s):

Laser Annealing ◽

Pulsed Laser ◽

Zno Nanostructures ◽

Correlation Effects ◽

Pulsed Laser Annealing

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Role of Autochthonous Filamentous Fungi in Bioremediation of a Soil Historically Contaminated with Aromatic Hydrocarbons

Applied and Environmental Microbiology ◽

10.1128/aem.72.1.28-36.2006 ◽

2006 ◽

Vol 72 (1) ◽

pp. 28-36 ◽

Cited By ~ 98

Author(s):

A. D'Annibale ◽

F. Rosetto ◽

V. Leonardi ◽

F. Federici ◽

M. Petruccioli

Keyword(s):

Aromatic Hydrocarbons ◽

Contaminated Soil ◽

Chloride Ions ◽

Lepidium Sativum ◽

Fungal Colonization ◽

Soil Toxicity ◽

Germination Test ◽

Lignin Peroxidases ◽

Ph Conditions

ABSTRACT Nine fungal strains isolated from an aged and heavily contaminated soil were identified and screened to assess their degradative potential. Among them, Allescheriella sp. strain DABAC 1, Stachybotrys sp. strain DABAC 3, and Phlebia sp. strain DABAC 9 were selected for remediation trials on the basis of Poly R-478 decolorization associated with lignin-modifying enzyme (LME) production. These autochthonous fungi were tested for the abilities to grow under nonsterile conditions and to degrade various aromatic hydrocarbons in the same contaminated soil. After 30 days, fungal colonization was clearly visible and was confirmed by ergosterol determination. In spite of subalkaline pH conditions and the presence of heavy metals, the autochthonous fungi produced laccase and Mn and lignin peroxidases. No LME activities were detected in control microcosms. All of the isolates led to a marked removal of naphthalene, dichloroaniline isomers, o-hydroxybiphenyl, and 1,1′-binaphthalene. Stachybotrys sp. strain DABAC 3 was the most effective isolate due to its ability to partially deplete the predominant contaminants 9,10-anthracenedione and 7H-benz[DE]anthracen-7-one. A release of chloride ions was observed in soil treated with either Allescheriella sp. strain DABAC 1 or Stachybotrys sp. strain DABAC 3, suggesting the occurrence of oxidative dehalogenation. The autochthonous fungi led to a significant decrease in soil toxicity, as assessed by both the Lepidium sativum L. germination test and the Collembola mortality test.

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