scholarly journals Maximizing Hydrogen Production by Cyanobacteria

2008 ◽  
Vol 63 (3-4) ◽  
pp. 226-232 ◽  
Author(s):  
Hermann Bothe ◽  
Stefanie Winkelmann ◽  
Gudrun Boison
Keyword(s):  
Energy Source ◽  
Hydrogen Production ◽  
Solar Energy ◽  
Energy Conversion ◽  
Molecular Hydrogen ◽  
Solar Energy Conversion ◽  
Clean Energy ◽  
Anabaena Variabilis ◽  
High Concentrations ◽  
Clean Energy Source

When incubated anaerobically, in the light, in the presence of C2H2 and high concentrations of H2, both Mo-grown Anabaena variabilis and either Mo- or V-grown Anabaena azotica produce large amounts of H2 in addition to the H2 initially added. In contrast, C2H2- reduction is diminished under these conditions. The additional H2-production mainly originates from nitrogenase with the V-enzyme being more effective than the Mo-protein. This enhanced H2-production in the presence of added H2 and C2H2 should be of interest in approaches to commercially exploit solar energy conversion by cyanobacterial photosynthesis for the generation of molecular hydrogen as a clean energy source

scholarly journals Solar Driven Energy Conversion Applications Based on 3C-SiC

2016 ◽  
Vol 858 ◽  
pp. 1028-1031 ◽  
Author(s):  
Jian Wu Sun ◽  
Valdas Jokubavicius ◽  
Lu Gao ◽  
Ian Booker ◽  
Mattias Jansson ◽  
...  
Keyword(s):  
Solar Energy ◽  
Energy Conversion ◽  
Water Splitting ◽  
Clean Energy ◽  
Energy Resources ◽  
Renewable Energy Resources ◽  
Intermediate Band ◽  
Boron Doped ◽  
Clean Energy Source ◽  
Photovoltaic Material

There is a strong and growing worldwide research on exploring renewable energy resources. Solar energy is the most abundant, inexhaustible and clean energy source, but there are profound material challenges to capture, convert and store solar energy. In this work, we explore 3C-SiC as an attractive material towards solar-driven energy conversion applications: (i) Boron doped 3C-SiC as candidate for an intermediate band photovoltaic material, and (ii) 3C-SiC as a photoelectrode for solar-driven water splitting. Absorption spectrum of boron doped 3C-SiC shows a deep energy level at ~0.7 eV above the valence band edge. This indicates that boron doped 3C-SiC may be a good candidate as an intermediate band photovoltaic material, and that bulk like 3C-SiC can have sufficient quality to be a promising electrode for photoelectrochemical water splitting.

Spatial distribution of active sites on a ferroelectric PbTiO3 photocatalyst for photocatalytic hydrogen production

2017 ◽  
Vol 198 ◽  
pp. 463-472 ◽  
Author(s):  
Rengui Li ◽  
Yue Zhao ◽  
Can Li
Keyword(s):  
Spatial Distribution ◽  
Hydrogen Production ◽  
Solar Energy ◽  
Energy Conversion ◽  
Electric Fields ◽  
Charge Separation ◽  
Active Sites ◽  
Solar Energy Conversion ◽  
Photogenerated Electrons ◽  
The Right

The separation of photogenerated charge carries is a challenging issue in artificial photocatalyst systems for solar energy conversion. It has been reported that spatial charge separation can take place between different facets of semiconductor-based crystals with regular morphology and facets, which could be used to rationally deposit cocatalysts on the right facets. However, the spatial separation of photogenerated electrons and holes is still a big challenge for a particulate photocatalyst without regular morphology and specific facets. In this work, we demonstrated that photogenerated electrons and holes can be regularly separated on ferroelectric PbTiO3 photocatalyst even without regular morphology and facets. The reduction cocatalyst and oxidation cocatalyst could be selectively formed on different sites via an in situ photochemical deposition method. It is found that the photoactivity and hydrogen production for PbTiO3 with spatially separated dual-cocatalysts is remarkably enhanced to more than 100 times greater compared to native PbTiO3, which is much higher than that the case of dual-cocatalysts with a random distribution. The intrinsic electric fields and spontaneous electric polarization in the bulk of PbTiO3 are proposed to play important roles in the spatial distribution of active sites on irregular PbTiO3 particles. Our work emphasizes the essential roles of two important factors, efficient charge separation strategy and the location of dual-cocatalysts on the right sites, to construct integrated artificial photocatalyst systems for solar energy conversion.

scholarly journals Solar Energy Use in Dryers as an Alternative Energy Source in Agriculture

2010 ◽  
Vol 67 (1) ◽  
Author(s):  
Mirela MILITARU ◽  
Elena POSTELNICU ◽  
Mihai CHIŢOIU ◽  
Valentin VLĂDUŢ
Keyword(s):  
Energy Source ◽  
Solar Energy ◽  
Alternative Energy ◽  
Energy Use ◽  
Clean Energy ◽  
Energy Sources ◽  
Negative Effects ◽  
Alternative Energy Source ◽  
Different Types ◽  
Clean Energy Source

Solar energy represents one of the future energy sources with a high potential, used as an alternative to conventional methods, especially during summer. The advantages of using solar energy are multiple, this type of energy being virtually endless and free, and its use has no negative effects on the environment, being regarded as a clean energy source. Solar energy has multiple applications in agriculture, one of its benefits being that it is used for dryers as an alternative energy source, especially in regions with a high solar potential. In this paper different types of fruits and vegetable dryers, nationally and abroad are presented, as well as results obtained from different methods of solar dryers.

scholarly journals Different forms of hydrogen production: a review and future perspectives

2022 ◽  
Vol 8 (2) ◽  
pp. 49-58
Author(s):  
Grazielle Cristina de Araujo ◽  
Jair Antonio Cruz Siqueira ◽  
Loreci Zanardini ◽  
João Felipe Peixoto Marques ◽  
Rafaela Lazzarin ◽  
...  
Keyword(s):  
Energy Source ◽  
Hydrogen Production ◽  
Literature Review ◽  
Greenhouse Gases ◽  
Fossil Fuels ◽  
Clean Energy ◽  
Biohydrogen Production ◽  
Research Centers ◽  
Future Perspectives ◽  
Clean Energy Source

There was a significant increase in the concern with climate issues, among them highlighted as the derivation of greenhouse gases from the burning fossil fuels, leading several research centers and researchers to seek new sources of less polluting energy, independent of the burn-based matrix of fuels. In this context, the present work has as main presenter a literature review, perspective and comparisons regarding the use of hydrogen as a clean energy source, presenting three main ways of obtaining it: a) through electrolysis using renewable sources; b) biohydrogen production, based on the photosynthesis of plants and algae; c) production through biodigesters.

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