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1.
Data Brief ; 48: 109281, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37383764

RESUMO

The data presented in this article are related to the research article entitled "Two-dimensional Pd-cellulose with optimized morphology for the effective solar to steam generation (Omelianovych et al., Desalination, 535, 115820 (2023)). We provide complementary analysis of the plasma synthesis parameters, such as plasma power optimization, which were omitted in the original research. The SEM images, XRD micrographs, XPS spectra, and evaporation performance of various plasma-synthesized Pd-cellulose absorbers are presented.

2.
Membranes (Basel) ; 11(1)2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33430261

RESUMO

The development of highly porous and thin separator is a great challenge for lithium-ion batteries (LIBs). However, the inevitable safety issues always caused by poor mechanical integrity and internal short circuits of the thin separator must be addressed before this type of separator can be applied to lithium-ion batteries. Here, we developed a novel multilayer poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) membrane with a highly porous and lamellar structure, through a combination of evaporation-induced phase separation and selective solvent etching methods. The developed membrane is capable of a greater amount of electrolyte uptake and excellent electrolyte retention resulting from its superior electrolyte wettability and highly porous structure, thereby offering better electrochemical performance compared to that of a commercial polyolefin separator (Celgard). Moreover, benefiting from the layered configuration, the tensile strength of the membrane can reach 13.5 MPa, which is close to the mechanical strength of the Celgard type along the transversal direction. The elaborate design of the multilayered structure allows the fabrication of a new class of thin separators with significant improvements in the mechanical and electrochemical performance. Given safer operation, the developed multilayer membrane may become a preferable separator required for high-power and high-energy storage devices.

3.
Nanoscale ; 13(1): 175-184, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33325955

RESUMO

This study is the first to quantify energy band alignments at a nanostructured TiO2/Au22(SG)18 cluster interface using X-ray photoelectron spectroscopy. The d-band of Au clusters shows band-like character and occupied states at the Fermi level are not detected. The results provide evidence of the existence of a finite optical energy gap in Au22(SG)18 clusters and the molecular-like nature of these clusters. The pinning position of the Fermi energy level at the interface was determined to be 2.8 and 1.3 eV higher than the top of the TiO2 valence band and the highest occupied molecular orbit level of the Au clusters, respectively. A diffuse reflectance and absorption analysis quantified a 3.2 eV bandgap of the TiO2 layer and a 2.2 eV energy gap between the highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO) levels of the Au clusters. Thus, a cliff-like offset of 0.5 eV between the LUMO level and the TiO2 conduction band was determined. The cliff-like offset of 0.5 eV provides room for improving the efficiency of metal-cluster-sensitized solar cells (MCSSC) further by lowering the LUMO level through a change in the cluster size. The offset of 0.5 eV between the HOMO level and the 3I-/I-3 redox level yields a remarkable loss-in-potential, which implies the possibility of increasing the open-circuit voltage further by properly replacing the redox couple in the MCSSCs.

4.
Data Brief ; 33: 106332, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33015259

RESUMO

The data presented in this article are related to the research article entitled "NiCoPt/Graphene-dot Nanosponge as a Highly Stable Electrocatalyst for Efficient Hydrogen Evolution Reaction in Acidic Electrolyte (N.-A. Nguyen et al., 2020) [1]. This article reports a simple method to synthesize NiCoPt/Graphene-dot as an electrocatalyst with low Pt loading but high hydrogen evolution reaction (HER) performance. The morphology of NiCoPt/Graphene-dot was analyzed by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) techniques. The structural and chemical properties of NiCoPt/Graphene-dot were investigated by using X-ray Powder Diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques.

5.
Nanoscale ; 6(1): 477-82, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24217311

RESUMO

NiO nanoparticles (NPs) were hybridized on the surface of reduced graphene oxide (RGO) by dry plasma reduction (DPR) at atmospheric pressure without any toxic chemicals and at a low temperature. NiO-NPs of 0.5-3 nm size, with a typical size of 1.5 nm, were uniformly hybridized on the surface of RGO. An XPS analysis and the Raman spectra also revealed the repair of some structural damage on the basal plane of the graphene. The material when applied to the counter electrode (CE) of dye-sensitized solar cells (DSCs) exhibited a power conversion efficiency of 7.42% (± 0.10%), which is comparable to a conventional Pt-sputtered CE (8.18% (± 0.08%)). This material outperformed CEs produced using NiO-NPs (1.53% (± 0.15%)), GO (4.48% (± 0.12%)) and RGO (5.18% (± 0.11)) due to its high electrochemical catalytic activity and high conductivity. The charge transfer resistance for NiO-NP-RGO was as low as 1.93 Ω cm(2), while those of a NiO-NP-immobilized electrode and a GO-coated electrode were 44.39 Ω cm(2) and 12.19 Ω cm(2), respectively, due to a synergistic effect.


Assuntos
Corantes/química , Grafite/química , Nanopartículas Metálicas/química , Níquel/química , Energia Solar , Fontes de Energia Elétrica , Eletrodos , Temperatura
6.
Nanoscale ; 5(24): 12237-44, 2013 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-24146088

RESUMO

Dry plasma reduction (DPR) is an excellent approach for easily, continuously, uniformly and stably hybridizing platinum nanoparticles (Pt-NPs) on a graphene-coated layer under atmospheric pressure without any toxic chemicals and at a low temperature. The Pt-NPs with a size of 0.5-4 nm and mostly 2 nm were stably and uniformly hybridized on the surface of reduced graphene oxide (RGO) after co-reduction of Pt precursor ions and GO to Pt atoms and RGO, respectively. XPS analysis also revealed a repair of structural damage on the basal plane of the graphene as well as chemical bonding between Pt-NPs and RGO after DPR. Thus, the Pt-NPs/RGO nanohybrids applied to the counter electrode of dye-sensitized solar cells (DSCs) exhibited robust stability as well as ultrahigh electrochemical catalytic activity and conductivity using less than 1% of the Pt exploited for the Pt-sputtered counter electrodes. Thus, the Pt-NPs/RGO nanohybrid fabricated by DPR could be an excellent material for a robust and low-cost counter electrode for DSCs.

7.
Int J Syst Evol Microbiol ; 57(Pt 11): 2532-2537, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17978214

RESUMO

A Gram-positive, non-motile, endospore-forming bacterial strain, designated Gsoil 420T, was isolated from soil of a ginseng field in Pocheon Province, South Korea, and was characterized, using a polyphasic approach, in order to determine its taxonomic position. The novel isolate consisted of strictly aerobic, rod-shaped cells and was able to grow in medium supplemented with up to 12% NaCl at 25 degrees C and pH 6.5-7.0. Comparative 16S rRNA gene sequence analysis showed that strain Gsoil 420T fell within the radiation of the cluster comprising Bacillus species and formed a coherent cluster with Bacillus niacini (16S rRNA gene sequence similarity, 98.6%), Bacillus bataviensis (98.6%), Bacillus soli (98.3%), Bacillus drentensis (98.0%), Bacillus novalis (98.0%), Bacillus vireti (97.9%), Bacillus foraminis (97.6%), Bacillus fumarioli (97.4%) and Bacillus jeotgali (97.0%). The levels of 16S rRNA gene sequence similarity with respect to other Bacillus species with validly published names were less than 96.8%. Strain Gsoil 420T had a genomic DNA G+C content of 44.9 mol% and the predominant respiratory quinone was MK-7. The major fatty acids were anteiso-C15:0 (33.9%), iso-C15:0 (24.5%) and iso-C14:0 (19.9%). These chemotaxonomic results supported the affiliation of strain Gsoil 420T to the genus Bacillus. However, low DNA-DNA relatedness values and distinguishing phenotypic characteristics allowed genotypic and phenotypic differentiation of strain Gsoil 420T from recognized Bacillus species. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Gsoil 420T represents a novel species of the genus Bacillus, for which the name Bacillus pocheonensis sp. nov. is proposed. The type strain is Gsoil 420T (=KCTC 13943T=DSM 18135T).


Assuntos
Bacillus/classificação , Bacillus/isolamento & purificação , Panax/crescimento & desenvolvimento , Cloreto de Sódio/metabolismo , Microbiologia do Solo , Aerobiose , Bacillus/química , Bacillus/genética , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , DNA Ribossômico/análise , Ácidos Graxos/análise , Genes de RNAr , Genótipo , Coreia (Geográfico) , Dados de Sequência Molecular , Fenótipo , Filogenia , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
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