2.3.4. Nitrogen Adsorption/Desorption Analysis (BET)

The specific surface area and pore size of the samples were measured by the specific surface area and pore size analyzer (ASAP2460, Micromeritics, Georgia, USA). Nitrogen adsorption–desorption was measured at 90 ◦C for 12h under nitrogen protection [41].

#### *2.4. Static Adsorption*
