Hydrogen photoproduction by use of photosynthetic organisms and biomimetic systems

Abstract

Hydrogen can be important clean fuel for future. Among different technologies for hydrogen production, oxygenic natural and artificial photosyntheses using direct photochemistry in synthetic complexes have a great potential to produce hydrogen, since both use clean and cheap sources: water and solar energy. Artificial photosynthesis is one way to produce hydrogen from water using sunlight by employing biomimetic complexes. However, splitting of water into protons and oxygen is energetically demanding and chemically difficult. In oxygenic photosynthetic microorganisms such as algae and cyanobacteria, water is split into electrons and protons, which during primary photosynthetic process are redirected by photosynthetic electron transport chain, and ferredoxin, to the hydrogen-producing enzymes hydrogenase or nitrogenase. By these enzymes, e- and H+ recombine and form gaseous hydrogen. Biohydrogen activity of hydrogenase can be very high but it is extremely sensitive to photosynthetic O2. In contrast, nitrogenase is insensitive to O2, but has lower activity. At the moment, the efficiency of biohydrogen production is low. However, theoretical expectations suggest that the rates of photon conversion efficiency for H2 bioproduction can be high enough (>10%). Our review examines the main pathways of H2 photoproduction by using of photosynthetic organisms and biomimetic photosynthetic systems.

Photobiological hydrogen production and artificial photosynthesis for clean energy: from bio to nanotechnologies

“…After the uptake hydrogenase, the electrons end up in the plastoquinone pool, and the associated pumping of protons to the thylakoid lumen may power ATP production. Figures partly drawn after Allakhverdiev et al (2009). Reprinted with permission from Allakhverdiev et al (2009).…”

“…Figures partly drawn after Allakhverdiev et al (2009). Reprinted with permission from Allakhverdiev et al (2009). Copyright (2009) by RSC Group Photosynth Res traditional combustion fuels.…”

“…Solar energy is the most abundant and easily accessible renewable energy source available for future sustainable production of fuel (Allakhverdiev et al 2009). Thus, effective use of solar energy to develop more cost-effective systems with improved ability to convert sunlight into chemical energy conserved in fuel, such as H 2 , is of utmost importance.…”

“…H 2 can also be produced by splitting water molecules by high-temperature thermochemical water splitting (HTWS) and electrolytic water splitting with nuclear high-temperature electrolysis (NHTE). Finally, H 2 can be produced by photo-driven water splitting, where the energy is provided by light from the sun (Allakhverdiev et al 2009(Allakhverdiev et al , 2010aMaurino and Weber 2013).…”

Solar Thermal and Efficient Solar Thermal/Electrochemical Photo Hydrogen Generation

“…A variety of approaches have been studied to achieve this important goal, for example, photosynthetic, direct or indirect photothermochemical, and photovoltaic or photoelectrochemical water splitting. As summarized in Table 21.1, each of these processes has exhibited a limited conversion of solar energy to hydrogen; photosynthetic, biological and photochemical solar water splitting [1][2][3][4][5] have exhibited solar energy to hydrogen conversion efficiencies, Z solar , on the order of only 1%; single [6-9] or multistep [10-14] photothermal …”