P-25, 55 i3 m2gsy; 2-1 Vanadium oxid has been deposited gn TiO (washed anatase, 10 m g ; Degussa Eurotitania, 46 m g-l) gy aqueous impregnation of (NH) [VO(C 0) ] and by reaction with VOCl org&Pc sol3eEttP. VO(OR) (R=lBu) and VO(acac) in Single applications of tl?;! last taree reagents form no z more than a mon!layer of vanadium oxide VO,, a monolayer being defined as 0.10 wt.% V,O$ per m of surface. When less than about four monolayers of VD are pre ent, there is in most cases only a single TPR peak: T,,, valueg, which increase with V 0 content, are almost independent of the method used but varv slightly with t&e5support (P-25 < Eurotitania < washed anatase). The 995 cm-l hand, characteristic of V=O in V205, VOX is present. only appears when more than a monolayer of In the sub-monolayer region, VD is best formulated as an oxohydroxy species bonded to two surface oxygens. AsXthe V 0 content is increased, layers of disordered V 0 are formed on limited ar a of the surface, but crystalline $2 V 0 only oc&F?s, probably on top of the disordered V 0 ezcseds about four monolayers, $ 7' when the V O5 content and takes the form of c cular crysta s exposing P only planes perpendicular to the a and b axes. INTRODUCTION A number of recent papers from our two laboratories have concerned the preparation, characterisation and catalytic properties of monolayers of vanadium oxide (VOX) on Ti02, principally as anatase [l-5]. These have been made chiefly by specific reactions between the vanadium precursor and the OH groups on the Ti02 surface: precursors used include VO(acac)2 in solution [2,3] and VOC13 both as vapour 141 and in solution [5]. These methods can be applied to give not more than a monolayer of VOX, this designation beinq used to denote that the species formed are not well-defined, but are certainly not equivalent to crystalline V205. However by repetition of the procedure [Z],

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The energy consumption in the world is increased in a significant way with passing of the time. The environmental demands in the developed nations are every time but severe as for the pollutant content in generating energy compounds, particularly, fuels. That has resulted in a high number of researchers studying new catalytic materials that satisfy this conditions. There are many inorganic solids with regular structures that incorporate spaces having molecular dimensions. Sheet silicates, often called clays, are cations exchangers.