Reactivity is often evaluated through metrics like turnover frequency (TOF) and turnover number (TON). TOF measures the number of substrate molecules that a single active site converts per unit time, while TON indicates the total number of conversions before deactivation. High TOF and TON values are indicative of a highly reactive catalyst. Techniques such as temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) are commonly used to assess reactivity by providing insights into the active sites and reaction mechanisms.
