Perovskites work as catalysts by providing active sites for chemical reactions on their surfaces. The electronic structure of perovskites can be modified by substituting different cations at the 'A' and 'B' sites. This allows for the optimization of properties such as band gap, surface area, and oxygen vacancy concentration, all of which are crucial for catalytic activity. For instance, the substitution of different metal ions can enhance the material's ability to adsorb and activate molecules, thereby improving catalysis efficiency.
