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In this review article, nanocatalysts for solar hydrogen production are the focus of discussion as they can contribute to the development of sustainable hydrogen production in order to meet future energy demands. Achieving this task is subject of scientific aspirations in the field of photo‐ and photoelectrocatalysis for solar water splitting where systems of single catalysts or tandem configurations are being investigated. In search of a suitable catalyst, a number of crucial parameters are laid out which need to be considered for material design, in particular for nanostructured materials that provide exceptional physical and chemical properties in comparison to their bulk counterparts. Apart from synthetic approaches for nanocatalysts, key parameters and properties of nanostructured photocatalysts such as light absorption, charge carrier generation, charge transport, separation and recombination, and other events that affect nanoscale catalysts are discussed. To provide a deeper understanding of these key parameters and properties, their contribution towards existing catalyst systems is evaluated for photo‐ and photoelectrocatalytic solar hydrogen evolution. Finally, an insight into hydrogen production processes is given, stressing the current development of sustainable hydrogen sources and presenting a perspective towards a hydrogen‐based economy. 相似文献
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Simona Casiglia Mariem Ben Jemia Luana Riccobono Elia Scandolera Felice Senatore 《Natural product research》2015,29(13):1201-1206
In this study the chemical composition of the essential oil from aerial parts of Moluccella spinosa L. collected in Sicily was evaluated by GC and GC-MS. The main components of M. spinosa L. were α-pinene (26.6%), caryophyllene oxide (16.8%) and β-caryophyllene (8.6%). A comparison with other studied oils of genus Moluccella is made. Antibacterial and antifungal activities against some microorganisms infesting historical textiles were also determined. 相似文献
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Aissaoui Ghania Belyagoubi Larbi Mouray Elisabeth Grellier Philippe Benmahdjoub Mariem 《Natural product research》2019,33(5):742-745
The objective of this study was to investigate the biological activities of Algerian algae, Sargassum vulgare, Cladostephus hirsutus and Rissoella verruculosa. Antimicrobial activity of the crude extracts and their fractions was assessed using the disc diffusion assay, the minimum inhibitory concentration and the minimum bactericidal concentration. Antiparasitic activity was studied in vitro against the blood stream forms of Trypanosoma brucei brucei and the intraerythrocytic stages of Plasmodium falciparum. Ethyl acetate (EA) fractions of the three tested algae showed more potent antimicrobial activity against S. aureus (7–14.5 mm) and B. cereus (7–10.75 mm), MIC values ranged from 0.9375 to 7.5 mg mL?1 and MBC values > 15 mg mL?1. Concerning the antiparasitic activity, EA factions of S. vulgare (IC50 = 9.3 μg mL?1) and R. verruculosa (IC50 = 11.0 μg mL?1) were found to be more effective against T. brucei brucei, whereas the three EA fractions were little active against P. falciparum. 相似文献
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Mariem Chaari Adel Matoussi 《Applied Physics A: Materials Science & Processing》2014,116(3):1149-1160
Undoped zinc oxide has been prepared at various growth temperatures by a conventional sintering process. The crystal structures of the prepared samples were studied by X-ray diffraction. The frequency-dependent dielectric dispersion of all the sintered ZnO ceramics was investigated in the temperature range from ?100 to 30 °C and in the frequency range from 1 Hz to 10 MHz by broadband dielectric spectroscopy. An analysis of the complex permittivity and electric modulus as a function of frequency has been performed assuming a distribution of relaxation times. The pellet sintered at 900 °C showed the lowest value of the dielectric strength. The temperature dependent of the parameter α is discussed. While the charge transport through the grain and grain boundary regions was examined by impedance spectroscopy. Activation energy values extracted from conduction measurements were found to be in the range of 0.09 and 0.3 eV. 相似文献
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Mariem Hammami Hanen Khadhraoui Abdelhak Othmani Mouldi Zouaoui 《Electroanalysis》2023,35(8):e202200458
In this work, we report the biosynthesis of CuCo2S4 nanoparticles (Bio-NPs) via hydrothermal method. The synthetized Bio-NPs-CuCo2S4 was studied as an active material of working electrode for electrochemical supercapacitor and non-enzymatic hydrazine sensor. The Bio.NPs-CuCo2S4/ITO electrode has a specific capacitance of 264 F/g at a current density of 1 A/g. Meanwhile, the electrode exhibits excellent electrochemical performances, such as an energy density of 33 Wh/Kg and a power density of 900 W/Kg. The Bio.NPs-CuCo2S4/ITO electrode for non-enzymatic hydrazine sensor exhibits a very high sensitivity of 2400 μA.mM−1.cm−2, a wide linear range from 0.001 to 1.400 mM and shows an excellent selectivity. 相似文献
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Two new phytochemical compounds, Tetranins A and B, 1-(3,5'-dihydroxy-4'-méthoxyphenyl)-2-phenylethanol 1 and 5,2'-dihydroxy-5'-methoxy-6,7-methylenedioxy-isoflavone 2, were isolated from the EtOAc extract of Salsola tetrandra roots. They exhibited a significant antioxidant effect in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Their structures were elucidated by extensive spectroscopic methods including 1-D-((1)H and (13)C) and 2-D-NMR experiments (CHcorr, HMBC, (1)H-(1)H COSY and NOESY) as well as high-resolution ES-MS and they were found to be quite active as antioxidants in the DPPH and ABTS assays. 相似文献