OK, so what's the catch here?
MIT's Daniel Nocera invents - essentially - artificial photosynthesis. Video.
Because... awesome!
2H+ + 2e- → H2 E = -0.41 V
2H2O → 4H+ + 2e- +O2 E = +0.82 V
H2O → ½ O2 + H2 ∆G = +1.23 eV
The Abstract:
The utilization of solar energy on a large scale requires its storage. In natural photosynthesis, energy from sunlight is used to rearrange the bonds of water to O2 and H2-equivalents. The realization of artificial systems that perform similar "water splitting" requires catalysts that produce O2 from water without the need for excessive driving potentials. Here, we report such a catalyst that forms upon the oxidative polarization of an inert indium tin oxide electrode in phosphate-buffered water containing Co2+. A variety of analytical techniques indicates the presence of phosphate in an approximate 1:2 ratio with cobalt in this material. The pH dependence of the catalytic activity also implicates HPO42– as the proton acceptor in the O2-producing reaction. This catalyst not only forms in situ from earth-abundant materials but also operates in neutral water under ambient conditions.
The MIT Energy Initiative (also: 50% more efficient fuel cells?)
MIT's Daniel Nocera invents - essentially - artificial photosynthesis. Video.
Because... awesome!
2H+ + 2e- → H2 E = -0.41 V
2H2O → 4H+ + 2e- +O2 E = +0.82 V
H2O → ½ O2 + H2 ∆G = +1.23 eV
The Abstract:
The utilization of solar energy on a large scale requires its storage. In natural photosynthesis, energy from sunlight is used to rearrange the bonds of water to O2 and H2-equivalents. The realization of artificial systems that perform similar "water splitting" requires catalysts that produce O2 from water without the need for excessive driving potentials. Here, we report such a catalyst that forms upon the oxidative polarization of an inert indium tin oxide electrode in phosphate-buffered water containing Co2+. A variety of analytical techniques indicates the presence of phosphate in an approximate 1:2 ratio with cobalt in this material. The pH dependence of the catalytic activity also implicates HPO42– as the proton acceptor in the O2-producing reaction. This catalyst not only forms in situ from earth-abundant materials but also operates in neutral water under ambient conditions.
The MIT Energy Initiative (also: 50% more efficient fuel cells?)
