Principles and test methods for the determination of the activity of photocatalytic materials and their application to modified building materials

Photocatalysts and photocatalytically modified materials based on titanium dioxide are used in a wide range of applications. Modified building materials are interesting for further research activities. These materials should be used as a substrate for photocatalysts to degrade a great variety of organic and inorganic pollutants like NO etc. Therefore methods to analyse the activity of these materials are necessary. Some national and international standards deal with photocatalytic degradation of different chemicals. However building materials show a different behaviour because pores and pH-values are not within their scope. Some standards and concepts were tested with building materials. A short overview of standards is given and some measurements are shown.