Photocatalytic assisted processes

Titanium dioxide is the reference photocatalyst and most of the Uterature reports refer to Degussa P25 as an etalon. However, this photocatalyst containing merely the Ti02-anatase form presents some drawbacks [7j  

Perovskites and Related Mixed Oxides Concepts and Applications, First Edition. 

Edited by Pascal Granger, Vasile I. Parvulescu, Serge Kaliaguine, and Wilfrid Prellier. 

Perovskites are among these multioxidic materials and their efficient photoca-talytic behavior was already reported in literature [7]. Many of these perovskites present a band structure, which is similar or very close with that of Ti02 [8], 

On this basis, the chapter will discuss examples of materials containing perov-skites and related oxides with photocatalytic activity. More specifically, the structural and morphological characteristics of titanates, niobates, tantalates, ferrites, aluminates, and transition metal-lanthanide mbced oxides will be evaluated in a close relation with their photocatalytic performances. 

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Sreethawong T, Ngamsinlapasathian S, Suzuki Y, Yoshikawa S (2005) Nanociystalline mesoporus Taz-based photocatalysts prepapred by surfactant-assisted templating sol-gel process photocatalytic H2 evolution. J Mol Catal A Chem 235 1-11... 

The photocatalytic ability of POM to induce bromide-assisted functionalization process was also studied by Molinari et al. [27] in the bromination of some aromatics and alkenes. They reported the possibility to convert phenol and anisole to the corresponding monobrominated derivates and a wide range of cydoalkenes to dibromides and bromohydrins, the last ones as intermediates for the formation of epoxides. 

Aaron Ortiz-Gomez, Benito Serrano-Rosales, Jesus Moreira-del-Rio, and Hugo de-Lasa, Mineralization of Phenol in an Improved Photocatalytic Process Assisted with Ferric Ions Reaction Network and Kinetic Modeling... 

In the case of semiconductor assisted photocatalysis organic compounds are eventually mineralized to carbon dioxide, water, and in the case of chlorinated compounds, chloride ions. It is not unusual to encounter reports with detection of different intermediates in different laboratories have been observed. For example, in the degradation of 4-CP the most abundant intermediate detected in some reports was hydroquinone (HQ) [114,115,123], while in other studies 4-chloro-catechol, 4-CC (3,4-dihydroxychlorobenzene) was most abundant [14,116-118, 121,163]. The controversy in the reaction intermediate identification stems mainly from the surface and hydroxyl radical mediated oxidation processes. Moreover, experimental parameters such as concentration of the photocatalyst, light intensity, and concentration of oxygen also contribute in guiding the course of reaction pathway. The photocatalytic degradation of 4-CP in Ti02 slurries and thin films... 

Mineralization of Phenol in an Improved Photocatalytic Process Assisted with Ferric Ions... 

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