Abstract

TiO2 and the related compounds have attracted keen attention in view of solar-to-chemical and electricity conversion, and photochemical environmental cleaning. For the better performance of such a photochemical property, there have being developed new photocatalysts, some of which contain more metal elements in the unit cell. Consequently their crystal structure and composition become more complex to make it more difficult to understand their elemental photocatalytic processes. 
  For example, SrTiO3(STO), which is one of the most simple complex oxide photocatalyst, can be regarded as a natural superlattice of SrO and TiO2 atomic layers along the <001> direction; the (001) surface has two possible termination layers of SrO and TiO2. This characteristic feature thus arises a new question: whether photochemical properties depend not only on crystal orientations, impurities and defects, but also on the choice of the termination layer, SrO or TiO2 on the (001) surface.
  In order to investigate photochemical properties depending on such atomic-scale controlled structure and composition, the photodecomposition of organic pentacene films grown on the nano-scale designed STO(001) surfaces would be a good model system. In my talk, at first we introduce a pulsed laser deposition technique to prepare TiO2- and SrO-terminated STO(001) surfaces and focus on the reaction kinetics for the photodecomposition of a monolayer pentacene films not only to understand the reaction mechanism but also to quantitatively discuss the termination effect on it. 

References

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