A Generic Description of the Relationship between Metal-Oxygen Bond Strength and Selectivity

A Generic Description of the Relationship between Metal-Oxygen Bond Strength and Selectivity 

The idea that the reactivity of the oxygen at the active site is important has been proposed by others (51 -53). One can extend these concepts to illustrate the relationship among the number of oxygen atoms available at the active site, the size of the site and the surface intermediate, and the reactivity of the oxygen using the following hypothetical example. 

One the other hand, consider another case that each of the two sites adsorbs one surface intermediate species. The reaction of this intermediate is 

Schematic drawing of the active sites (A) V04 unit in Mg3(V04)2 (B) V207 unit in Mg2V207 (C) V208 unit in (V0)2P207. Open circles are O ions and solid circles are V ions. 

Change in heat of removal of lattice oxygen with degree of reduction of the site measured as (A) number of O removed per metal ion (B) number of O removed per site (or per adsorbed molecule). Hatched bars are for M04 sites and dotted bars are for M207 sites (from Ref. 39). 

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