Iron oxide-based pair

As described in the experimental section, the tribo-pairs used in this work were prepared in different ways from the substrates (waveguides) used in the OWLS experiment, although all are either silicon oxide- or iron oxide-based materials. It is thus noted that the actual amount of the adsorbed polymers on each tribo-pair may be slightly different from those shown in figure 4. 

Charvin, P., Abanades, S., Flamant, G., Lemort, F., 2007. Two-step water splitting thermo-chemical cycle based on iron oxide redox pair for solar hydrogen production. Energy 32 (7), 1124-1133. 

Another strategy (which could be related to seeded emulsion polymerization) was recently developed by Ding et al. [142,143] to promote the formation of polymer chains close to the surface of iron oxides. The procedure, based on the formation of polymer-monomer pairs, was the following PVA-coated Fc304 nanoparticles were mixed with chitosan (CS) and AA polymer-monomer pair to form micelles... 

The SCL process based on iron oxide/iron monoxide/iron metal (Fe203/ FeO/Fe) redox pairs can be written as follows ... 

The most common thermochemical cycles based on this redox pair are the iron oxide, cerium—cerium oxide, and Zn—ZnO cycles. Many other thermochemical cycles are being developed, some of which are discussed below, in terms of reactions used to split water, advantages, and disadvantages. 

In a complexation reaction, a Lewis base donates a pair of electrons to a Lewis acid. In an oxidation-reduction reaction, also known as a redox reaction, electrons are not shared, but are transferred from one reactant to another. As a result of this electron transfer, some of the elements involved in the reaction undergo a change in oxidation state. Those species experiencing an increase in their oxidation state are oxidized, while those experiencing a decrease in their oxidation state are reduced, for example, in the following redox reaction between fe + and oxalic acid, H2C2O4, iron is reduced since its oxidation state changes from -1-3 to +2. 

The cyanide ion is called a pseudohalide ion because it behaves like Cl- in forming an insoluble, white silver salt, AgCN. In complex ions such as Fe(CN)63-, CN - acts as a Lewis base (Section 15.16), bonding to transition metals through the lone pair of electrons on carbon. In fact, the toxicity of HCN and other cyanides is due to the strong bonding of CN- to iron(III) in cytochrome oxidase, an important enzyme involved in the oxidation of food molecules. With CN attached to the iron, the enzyme is unable to function. Cellular energy production thus comes to a halt, and rapid death follows. 

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