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1.
Materials (Basel) ; 15(22)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36431719

RESUMO

In the present report, we synthesized highly porous 1D nanobelt-like cobalt phosphate (Co2P2O7) materials using a hydrothermal method for supercapacitor (SC) applications. The physicochemical and electrochemical properties of the synthesized 1D nanobelt-like Co2P2O7 were investigated using X-ray diffraction (XRD), X-ray photoelectron (XPS) spectroscopy, and scanning electron microscopy (SEM). The surface morphology results indicated that the deposition temperatures affected the growth of the 1D nanobelts. The SEM revealed a significant change in morphological results of Co2P2O7 material prepared at 150 °C deposition temperature. The 1D Co2P2O7 nanobelt-like nanostructures provided higher electrochemical properties, because the resulting empty space promotes faster ion transfer and improves cycling stability. Moreover, the electrochemical performance indicates that the 1D nanobelt-like Co2P2O7 electrode deposited at 150 °C deposition temperature shows the maximum specific capacitance (Cs). The Co2P2O7 electrode prepared at a deposition temperature 150 °C provided maximum Cs of 1766 F g-1 at a lower scan rate of 5 mV s-1 in a 1 M KOH electrolyte. In addition, an asymmetric hybrid Co2P2O7//AC supercapacitor device exhibited the highest Cs of 266 F g-1, with an excellent energy density of 83.16 Wh kg-1, and a power density of 9.35 kW kg-1. Additionally, cycling stability results indicate that the 1D nanobelt-like Co2P2O7 material is a better option for the electrochemical energy storage application.

2.
Polymers (Basel) ; 12(8)2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32727000

RESUMO

A binder-free process for the electrode preparation for supercapacitor application was suggested by drop casting graphene nanoplatelets on a carbon fiber (GnP@CF) followed by electrodeposition of Ni nanoparticles (NPs). The microstructure of the electrode showed that Ni was homogeneously distributed over the surface of the GnP@CF. XRD analysis confirmed the cubic structure of metallic Ni NPs. The Ni-GnP@CF electrode showed excellent pseudocapacitive behavior in alkaline solution by exhibiting a specific capacitance of 480 F/g at 1.0 A/g, while it was 375 F/g for Ni@CF. The low value of series resistance of Ni-GnP@CF (1 Ω) was attributed to the high capacitance. The enhanced capacitance of the electrode could be correlated to the highly nanoporous structure of the composite material, synergetic effect of the electrical double layer charge-storage properties of graphene, and the pseudocapacitive nature of Ni NPs.

3.
Colloids Surf B Biointerfaces ; 184: 110500, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541889

RESUMO

In this work, the extraordinary properties of CuO addition on the morphology and supercapacitive performance of Mn2O3 electrodes were demonstrated. Concisely, CuO/Mn2O3 thin films were prepared by an easy and inexpensive successive ionic layer adsorption and reaction (SILAR) method. The prepared thin films were characterized by various sophisticated physiochemical systems. The results demonstrated formation of Mn2O3 thin films with noteworthy morphological alteration upon introduction of CuO. Furthermore, a significant effect of CuO introduction was observed on the electrocatalytic properties of the nanostructured Mn2O3 electrodes. At 3% CuO doping, the Mn2O3 electrodes displayed the maximum specific capacitance owing to formation of nanoplate-like structures. The enhanced specific capacitance attained for 3% CuO doping in the Mn2O3 electrode was 500 F/g at 5 mV/s in a 3 M KOH electrolyte. All results confirmed the plausible potential of the CuO/Mn2O3 electrode for supercapacitor applications.


Assuntos
Cobre/química , Capacitância Elétrica , Compostos de Manganês/química , Nanoestruturas/química , Óxidos/química , Eletrodos , Nanotubos/química , Tamanho da Partícula , Propriedades de Superfície
4.
Ultrason Sonochem ; 51: 49-57, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30514485

RESUMO

The effect of ultrasonic treatment and deposition time on nanoflake-like Co(OH)2 thin films were prepared using the potentiostatic mode of electrodeposition method on stainless steel substrates by a nitrate reduction reaction. After ultrasonic treatment, we used stainless steel substrates for deposition of the nanoflakes like Co(OH)2 thin films. The effect of deposition times and electrolytes on different physico-chemical properties of Co(OH)2 was investigated in detail, such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), and electrochemical testing. After ultrasonic treatment Co(OH)2 thin films had devolvement of the uniform and interconnected formation of nanoflakes nanostructures. Supercapacitor performance of the Co(OH)2 electrodes suggest that, specific capacitance are depends on the surface morphology, and Co(OH)2 electrodes after ultrasonic treatment exhibited higher performance than without ultrasonication. The maximum specific capacitance of the 30 min. deposited Co(OH)2 nanoflakes exceeded 276 Fg-1 in 0.5M KOH electrolyte at 5 mVs-1 scan rate.

5.
Colloids Surf B Biointerfaces ; 181: 1004-1011, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31382327

RESUMO

We report the effect of ionic liquids on chemically synthesized hierarchical-like copper oxide (CuO) thin films for supercapacitor applications. Concisely, the CuO thin films were deposited via chemical bath deposition (CBD) using 2-dimethylimidazolium chloride [HPDMIM(C1)], 1-(2',3'-dihydroxypropyl)-3-methylimidazolium chloride [DHPMIM(C1)], and N-(3-methyl-2-oxopropyl)pyridine chloride [MOCPP(C1)] ionic liquid solvents. The effects of the ionic liquid solvents on the morphological evolution of the as-prepared films were analyzed, and electrochemical properties were investigated. The highest specific capacitance was achieved for the electrode with a nanosheet-like structure produced by functionalization with the HPDMIM(C1) ionic liquid. The maximum specific capacitance achieved for the HPDMIM(C1):CuO hybrid electrode was 464 F g-1 at 5 mV s-1 in a 1 M Na2SO4 electrolyte. Thus, our findings, in addition to the stability of the HPDMIM(C1):CuO, indicate that it is a candidate for energy-storage applications.


Assuntos
Cobre/química , Capacitância Elétrica , Líquidos Iônicos/química , Nanoestruturas/química , Técnicas Eletroquímicas , Eletrodos , Tamanho da Partícula , Solventes/química , Propriedades de Superfície
6.
Sci Rep ; 9(1): 13717, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31548661

RESUMO

Here, we developed a new approach to synthesize NiCo2S4 thin films for supercapacitor application using the successive ionic layer adsorption and reaction (SILAR) method on Ni mesh with different molar ratios of Ni and Co precursors. The five different NiCo2S4 electrodes affect the electrochemical performance of the supercapacitor. The NiCo2S4 thin films demonstrate superior supercapacitance performance with a significantly higher specific capacitance of 1427 F g-1 at a scan rate of 20 mV s-1. These results indicate that ternary NiCo2S4 thin films are more effective electrodes compared to binary metal oxides and metal sulfides.

7.
J Intellect Disabil Res ; 52(Pt 4): 275-86, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18205754

RESUMO

Historically, individuals with intellectual disability (ID) have been excluded from pain research and assumed to be insensitive or indifferent to pain. The weight of the evidence suggests that individuals with ID have been subject to practices and procedures with little regard for their ability to experience or express pain. A number of issues central to improving understanding of pain in ID will be introduced and current research related to the definition of pain and its social context, underlying sensory and metabolic systems and factors influencing judgments about the ability to experience pain will be reviewed. Accumulating evidence from interdisciplinary research designed to improve assessment, understand individual differences, and evaluate bias and beliefs about pain suggests that new perspectives are emerging and beginning to shape an innovative frontier of research that will ultimately pay tremendous dividends for improving the quality of life of individuals with ID.


Assuntos
Deficiência Intelectual/psicologia , Dor/psicologia , Humanos , Comunicação Interdisciplinar
8.
Colloids Surf B Biointerfaces ; 164: 255-261, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29413604

RESUMO

In this paper, we chemically synthesized interconnected nanoflake-like CdS thin films for photoelectrochemical solar cell applications and subsequently irradiated them with electron beam irradiation at various doses of irradiation. The as-synthesized and irradiated samples were characterized by means of X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and electrochemical measurements. XRD and XPS results confirmed the formation of CdS with a hexagonal crystal structure. FE-SEM and HR-TEM studies confirmed the photoelectrochemical performance, which was dependent on the surface morphology. The calculated values for efficiency demonstrated an outstanding photoelectrochemical performance with a fill factor of 0.38 and efficiency of 3.06% at 30 kGy. The high photoelectrochemical performance may be due to the interconnected nanoflake-like nanostructure and higher active surface area of the CdS samples. These results show that the electron beam irradiation is capable as an electrode for photoelectrochemical solar cells.


Assuntos
Compostos de Cádmio/química , Técnicas Eletroquímicas/métodos , Elétrons , Nanoestruturas/química , Fotoquímica/métodos , Sulfetos/química , Eletrodos , Nanoestruturas/ultraestrutura , Fenômenos Ópticos , Espectroscopia Fotoeletrônica , Energia Solar , Difração de Raios X
9.
Ultrason Sonochem ; 40(Pt A): 314-322, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28946430

RESUMO

This paper reports the effect of electron beam irradiation on CuO thin films synthesized by the successive ionic layer adsorption and reaction (SILAR) method on copper foil for supercapacitor and biocompatibility application. Pristine and irradiated samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and electrochemical study. Pristine and irradiated CuO films were pure monoclinic phase, with uniform nanostructures over the whole copper foil. After irradiation, CuO samples had formed innovative nanostructures. Biocompatibility of pristine and irradiated CuO samples suggest that CuO sample is non-toxic and ecofriendly. The specific capacitance of pristine and irradiated CuO strongly depends on surface morphology, and CuO electrodes after irradiation showed superior performance than pristine CuO. The highest specific capacitance of the 20kGy irradiated CuO nanoflowers exceeded 511Fg-1 at 10mVs-1 in 1M KOH electrolyte. Irradiated CuO samples also showed lower ESR, and were superior to other report electrical energy storage materials.


Assuntos
Cobre/química , Elétrons , Teste de Materiais , Nanoestruturas/química , Cobre/farmacologia , Eletroquímica , Eletrodos , Escherichia coli/efeitos dos fármacos , Fenômenos Mecânicos , Propriedades de Superfície
10.
Sci Rep ; 7(1): 9764, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28852122

RESUMO

In this study, hierarchical interconnected nickel cobalt sulfide (NiCo2S4) nanosheets were effectively deposited on a flexible stainless steel foil by the chemical bath deposition method (CBD) for high-performance supercapacitor applications. The resulting NiCo2S4 sample was characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and electrochemical measurements. XRD and X-ray photoelectron spectroscopy (XPS) results confirmed the formation of the ternary NiCo2S4 sample with a pure cubic phase. FE-SEM and HR-TEM revealed that the entire foil surface was fully covered with the interconnected nanosheets like surface morphology. The NiCo2S4 nanosheets demonstrated impressive electrochemical characteristics with a specific capacitance of 1155 F g-1 at 10 mV s-1 and superior cycling stability (95% capacity after 2000 cycles). These electrochemical characteristics could be attributed to the higher active area and higher conductivity of the sample. The results demonstrated that the interconnected NiCo2S4 nanosheets are promising as electrodes for supercapacitor and energy storage applications.

11.
Colloids Surf B Biointerfaces ; 156: 165-174, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28528133

RESUMO

In this research article, we report hybrid nanomaterials of copper hydroxide/copper oxide (Cu(OH)2/CuO). A thin films were prepared by using a facile and cost-effective successive ionic layer adsorption and reaction (SILAR) method. As-synthesized and hybrid Cu(OH)2/CuO with two different surfactants polyvinyl alcohol (PVA) and triton-X 100 (TRX-100) was prepared having distinct morphological, structural, and supercapacitor properties. The surface of the thin film samples were examined by scanning electron microscopy (SEM). A nanoflower-like morphology of the Cu(OH)2/CuO nanostructures arranged vertically was evidenced on the stainless steel substrate. The surface was well covered by nanoflake-like morphology and formed a uniform Cu(OH)2/CuO nanostructures after treating with surfactants. X-ray diffraction patterns were used to confirm the hybrid phase of Cu(OH)2/CuO materials. The electrochemical properties of the pristine Cu(OH)2/CuO, PVA:Cu(OH)2/CuO, TRX-100:Cu(OH)2/CuO films were observed by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy technique. The electrochemical examination reveals that the Cu(OH)2/CuO electrode has excellent specific capacitance, 292, 533, and 443Fg-1 with pristine, PVA, and TRX-100, respectively in 1M Na2SO4 electrolyte solution. The cyclic voltammograms (CV) of Cu(OH)2/CuO electrode shows positive role of the PVA and TRX-100 to enhance supercapacitor performance.


Assuntos
Cobre/química , Eletrodos , Hidróxidos/química , Octoxinol/química , Álcool de Polivinil/química , Espectroscopia Dielétrica , Eletroquímica , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
12.
J Chromatogr ; 426(2): 239-47, 1988 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-3392138

RESUMO

Carbamylation of the N-terminal valine of haemoglobin with methyl isocyanate in rats and rabbits has been demonstrated in vitro and in vivo by gas chromatography. N-Methylcarbamylated haemoglobin, converted by cyclization into 3-methyl-5-isopropylhydantoin, has been quantified by gas chromatography. Standard hydantoin was synthesized, chemically characterized and used for calibration. The method is simple and reliable in the concentration range 0.06-2 nmol. Carbamylation of haemoglobin by methyl isocyanate in vivo in rats can be identified only above a dose of 1.05 mg/l in inhalation exposures. It is inferred that methyl isocyanate in the "active" form crosses the alveolar and erythrocyte membranes and carbamylates the haemoglobin.


Assuntos
Antidrepanocíticos/farmacologia , Cianatos/farmacologia , Hemoglobinas/análise , Isocianatos , Animais , Antidrepanocíticos/síntese química , Cromatografia Gasosa , Cianatos/síntese química , Hemólise/efeitos dos fármacos , Técnicas In Vitro , Coelhos , Ratos
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