09-05-2013, 03:07 PM
Secrets of the first practical artificial leaf
[attachment=53650]
Abstract
To convert the energy of sunlight into chemical energy, the leaf splits water via the photosynthetic process
to produce molecular oxygen and hydrogen, which is in a form of separated protons and electrons. The primary steps of natural photosynthesis involve the absorption of sunlight and its conversion into spatially
separated electron - hole pairs. The holes of this wireless current are captured by the oxygen evolving
complex (OEC) of photosystem II (PSII) to oxidize water to oxygen. The electrons and protons produced as
a byproduct of the OEC reaction are captured by ferrodoxin of photosystem I. With the aid of ferrodoxin -
NADP+ reductase, they are used to produce hydrogen in the form of NADPH. For a synthetic material to
realize the solar energy conversion function of the leaf, the light-absorbing material must capture a solar
photon to generate a wireless current that is harnessed by catalysts, which drive the four electron/hole
fuel-forming water-splitting reaction under benign conditions and under 1 sun (100 mW/cm2) illumination.
[attachment=53650]
Abstract
To convert the energy of sunlight into chemical energy, the leaf splits water via the photosynthetic process
to produce molecular oxygen and hydrogen, which is in a form of separated protons and electrons. The primary steps of natural photosynthesis involve the absorption of sunlight and its conversion into spatially
separated electron - hole pairs. The holes of this wireless current are captured by the oxygen evolving
complex (OEC) of photosystem II (PSII) to oxidize water to oxygen. The electrons and protons produced as
a byproduct of the OEC reaction are captured by ferrodoxin of photosystem I. With the aid of ferrodoxin -
NADP+ reductase, they are used to produce hydrogen in the form of NADPH. For a synthetic material to
realize the solar energy conversion function of the leaf, the light-absorbing material must capture a solar
photon to generate a wireless current that is harnessed by catalysts, which drive the four electron/hole
fuel-forming water-splitting reaction under benign conditions and under 1 sun (100 mW/cm2) illumination.