Surface area measurement from temperature programmed desorption data

The approaches shown in this application note illustrate the possibilities of TPD (temperature programmed desorption) analysis and their relevance for analyzing active surface areas in transition metal-based catalysts with carrier substrates. It gives operators and scientists a possibility to evaluate the dispersion of these metal centers and their respective accessible surface for chemical processes. Quantification of the probe gases (which are usually tailored towards the metal in question, e.g., hydrogen for platinum, etc.) is usually carried out by means of a thermal conductivity sensor, which is put directly into the carrier gas stream. However, different analytical approaches can be used as well or combined with one another, such as mass spectroscopy, infrared spectroscopy and gas chromatography among others.