Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Environ Technol ; 43(4): 605-616, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32762618

RESUMO

The phytosynthesis of metal oxides nanoparticles (NPs) has been extensively reported; yet mechanism involved and incorporated bioactive compounds in the synthesized NPs are still need to be investigated. In this regard, here an efficient sustainable co-precipitation synthesis of zinc oxide nanoparticles (ZnO NPs) has been developed, employing hydrothermal reactions, using organic compounds of Nasturtium officinale leaves. Pure hexagonal wurtzite ZnO was identified by X-ray diffraction and NPs in the size range of 50-60 nm were observed by field emission scanning electron microscopy. X-ray photoelectron spectroscopy revealed surface modification of ZnO by functional groups associated with the incorporated bio active compounds of Nasturtium officinale. The phyto-functionalized ZnO NPs having anoptical direct band gap of 3.29 eV and optical band gap energy of 2.85 eV were evaluated by cyclic voltammetry at various scan rates, galvanostatic charge-discharge at a range of current densities and electrochemical impedance spectroscopy (Z' vs. Z″ and Z vs. frequency) in aqueous electrolyte. The fabricated ZnO-based electrode revealed a specific capacitance of 86.5 F/g at 2 mV/s with 97% coulombic efficiency for 2000 cycles. The good electrochemical conductivity was demonstrated by lower internal resistance of 1.04 Ω. Therefore, the present study suggested the significant potential of organic compounds incorporated ZnO NPs towards supercapacitor.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Eletrodos , Folhas de Planta , Difração de Raios X
2.
Nanomaterials (Basel) ; 10(8)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32717992

RESUMO

This communication reports the synthesis of bis(diisobutyldithiophosphinato)lead(II) complex and its subsequent application as a single source precursor for the nanostructured deposition of lead sulphide semiconductors and its impedance to explore its scope in the field of electronics. Synthesized complex was characterized by microelemental analysis, nuclear magnetic resonance spectroscopy, infrared spectroscopy and thermogravimetric analysis. This complex was decomposed using the aerosol-assisted chemical vapour deposition technique at different temperatures to grow PbS nanostructures on glass substrates. These nanostructures were analyzed by XRD, SEM, TEM and EDX methods. Impedance spectroscopic measurements were performed for PbS in the frequency range of 40 to 6 MHz at room temperature. In a complex impedance plane plot, two relaxation processes were exhibited due to grains and grain boundaries contribution. A high value of dielectric constant was observed at low frequencies, which was explained on the basis of Koops phenomenological model and Maxwell-Wagner type polarization. Frequency-dependent AC conductivity results were compliant with Jonscher power law, while capacitance-voltage loop had a butterfly shape. These impedance spectroscopic results have corroborated the ferroelectric nature of the resultant PbS nanodeposition.

3.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): m949, 2010 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-21588179

RESUMO

The title complex, [Cu(0.31)Ni(0.69)(C(5)H(7)O(2))(2)], was isolated from the reaction of bis-(N,N-dimethyamino-ethanol)copper(II) with bis-(acetyl-acetonato)nickel(II), which yielded crystals with mixed sites at the central metal position; the refined copper-nickel occupancy ratio is 0.31 (4):0.69 (4). Two acetyl-acetonate ligands, related by a centre of symmetry, are coordinated to the central metal atom in a square-planar configuration while the methyne C atoms of the acetyl-acetonate ligands, ca 3.02 Šaway, are orthogonal to this plane at the metal site.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA