Oxygen and hydrogen production

It might be thought that photogeneration of electrons and holes in a semiconductor with normally a small population of one or other (or both) charge carrier would result in both hydrogen and oxygen production at the interface, through the reactions ... 

Such cells are called fuel cells and were discovered as long ago as 1839 by Sir William Grove, who noticed that, when water had been electrolyzed and the hydrogen and oxygen products were left in contact with the electrodes, the cell could run backward, producing a current in an external circuit. Yet it is only relatively recently that fuel cells have attracted major industrial interest. For reasons that will emerge later, the reaction usually chosen is that discovered by Grove ... 

Cyclic Water Cleavage — Hydrogen and Oxygen Production via Electron Transfer Catalysis 523... 

Figure 4. Variation of electrode potentials (tt) with pH for hydrogen (---------) and oxygen (-----) production from water...

More recently, water soluble zinc porphyrins which can absorb up to 45% of the solar radiation117 have been studied118 for both hydrogen and oxygen production. 

Examination of the various half reactions for hydrogen and oxygen production described in Sections 61.5.4.2-61.5.4.5 suggests that some of these might be coupled to give cyclic water cleavage. 

In addition to the properties of micelles described above, vesicles, which are bilayer structures and can be considered to be model membranes, separate two distinct aqueous phases an entrapped or inner water pool and the bulk aqueous phase. In principle, therefore, electron transfer may be possible across the bilayer and the sites of hydrogen and oxygen production in a water splitting system can be separated spatially. 

OR type The oxidation and reduction power is strong enough to promote hydrogen and oxygen production. Examples include Ti02, SrTiOj, and CdS. OR indicates a strong ability for both oxidation and reduction. 

Serban, M., M.A. Lewis, J.K. Basco (2004), Kinetic Study of the Hydrogen and Oxygen Production Reactions in the Copper-chloride Thermochemical Cycle , AIChE 2004 Spring National Meeting, New Orleans, LA, 25-29 April. 

N.B., Hydrogen (and oxygen) production by the met Hanoi-water splitting cycle,... 

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