What are the different methods of Physical Activation?
Thermal Activation Thermal activation involves heating the catalyst to high temperatures in an inert or reactive atmosphere. This process helps in removing impurities, increasing surface area, and creating a more porous structure. For instance, the calcination process used in the preparation of metal oxides as catalysts often involves thermal activation.
Plasma Treatment Plasma treatment employs ionized gases at low temperatures to modify the surface properties of the catalyst. This method is particularly effective in introducing functional groups onto the catalyst surface, thereby enhancing its reactivity. Plasma-activated catalysts are often used in applications like environmental remediation and fuel cells.
Mechanical Milling Mechanical milling involves the use of mechanical force to grind the catalyst material into finer particles. This process increases the surface area and exposes more active sites. High-energy ball milling is a common technique used for this purpose, particularly in the preparation of nanoparticle catalysts.
