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1.
Int J Mol Sci ; 24(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37298197

RESUMO

Although water splitting is a promising method to produce clean hydrogen energy, it requires efficient and low-cost catalysts for the oxygen evolution reaction (OER). This study focused on plasma treatment's significance of surface oxygen vacancies in improving OER electrocatalytic activity. For this, we directly grew hollow NiCoPBA nanocages using a Prussian blue analogue (PBA) on nickel foam (NF). The material was treated with N plasma, followed by a thermal reduction process for inducing oxygen vacancies and N doping on the structure of NiCoPBA. These oxygen defects were found to play an essential role as a catalyst center for the OER in enhancing the charge transfer efficiency of NiCoPBA. The N-doped hollow NiCoPBA/NF showed excellent OER performance in an alkaline medium, with a low overpotential of 289 mV at 10 mA cm-2 and a high stability for 24 h. The catalyst also outperformed a commercial RuO2 (350 mV). We believe that using plasma-induced oxygen vacancies with simultaneous N doping will provide a novel insight into the design of low-priced NiCoPBA electrocatalysts.


Assuntos
Ferrocianetos , Hidrogênio , Níquel , Oxigênio
2.
J Innov Entrep ; 11(1): 15, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35194539

RESUMO

This research explores the influences of selfish personalities of the Dark Triad on start-up intention and motives based on a sample of 400 university students in Vietnam, discovering mixed effects of narcissism, psychopathy, and Machiavellianism. A high level of narcissism and Machiavellianism leads to high start-up intention. There is a negative relationship of Machiavellianism with pro-social motive and a positive association with selfish entrepreneurship. In addition, narcissism is positively associated with pro-social start-up motives. This study has found no effect of psychopathy but a positive link to selfish entrepreneurial motivation. Implications have been suggested for educators and investors.

3.
Materials (Basel) ; 14(23)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34885371

RESUMO

The paper presents the results of a study of the mechanism for reducing the moisture resistance of sulfur-extended asphalt concrete. It is shown that a decrease in moisture resistance occurs due to the occurrence of chemical and physical processes. At the same time, it was found that during the manufacture of sulfur-bitumen composites, toxic gases H2S and SO2 are formed, which are capable of interacting with a mineral filler, as well as the interaction of sulfur with a mineral powder with the formation of sulfur-containing water-soluble salts, the extraction of which leads to a decrease in the moisture resistance of sulfur-bitumen materials. The change in the rate of leaching of these substances from the composite is due to the physical process caused by the crystallization of sulfur and the formation of a capillary structure, which significantly increases the rate of leaching of calcium and magnesium salts, which are products of dissolution or hydrolytic decomposition of water-soluble products of the interaction of sulfur, H2S and SO2 gases with calcium and magnesium carbonates. The intensity of chemical and physical processes intensifies with an increase in the amount of sulfur in sulfur-bitumen materials.

4.
J Colloid Interface Sci ; 583: 425-434, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33011411

RESUMO

The development of a rapid, selective, and sensitive sensor to precisely monitor nitrite oxidation is of growing importance, given the strong interest in the protection of drinking water quality, treatment of wastewater, food production, and control of remediation processes. In this research, we successfully fabricated a hybrid originated from worm-like gold nanowires (Au WNWs) assembled on a high-quality carbon nanofibers-graphene (CNFs-Gr) hybrid network through a facile synthesis method. The hybrid as a binder-free sensor exhibited excellent activity towards nitrite detection in phosphate buffer solution (pH of 7.4) with a wide linear detection range of (1.98 µM - 3.77 mM), excellent sensitivity of 836 µA cm-2 mM-1, low detection limit of 1.24 µM, and long-term durability. The results were attributed to a special synergistic effect originating from unique hybridization of Au WNWs with large-area CNFs-Gr network to produce more electroactive sites and excellent conductivity, favorably boosting catalytic performance of the sensor. The successful fabrication of Au WNWs/CNFs-Gr suggested an interesting candidate for practically determining low-level nitrite in analytical applications.

5.
Biosens Bioelectron ; 139: 111327, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121438

RESUMO

The sensitivity, selectivity, and stability of an electrochemical sensor for detecting small biomolecules can be significantly upgraded through properly controlling the morphology and chemical structure of electrocatalyst. Herein, we fabricated a unique hierarchical nanostructure based on Cu@CuxO nanowires (NWs) array uniformly depositing with a layer of gold nanoparticles (2-3 nm) through a simple electroless deposition process. The Au-Cu@CuxO NWs hybrid was successfully applied as a novel binder-free self-supported biosensor towards L-cysteine detection with low limit of detection (1.25 µM), wide linear detection range (1.25 µM-1.94 mM), long-term stability (four weeks), and excellent selectivity. In addition, the hybrid-based sensor accurately detected L-cysteine in real samples. It was found that the obtained nanostructure with the formation of strong interaction between Au and Cu phase produces synergistic effects, which improve exposed electroactive site number, accelerate charge transfer rate, and increase surface area, thereby boosting the sensing performance. The results open a potential way to develop electrochemical sensor for efficiently detecting not only L-cysteine but also other small molecules with high sensitivity, accuracy, stability, and cost-effectiveness in health care and disease diagnosis.


Assuntos
Técnicas Biossensoriais , Cobre/química , Cisteína/isolamento & purificação , Técnicas Eletroquímicas , Nanopartículas Metálicas/química , Cisteína/química , Ouro/química , Humanos , Limite de Detecção , Nanofios/química , Oxirredução
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