N2 adsorption curve of mesoporous SiO2: A neglected characterization technique

Mesoporous SiO2 sieve and SiO2 nanoparticles were synthesized by a traditional method in the presence and absence of tri-block copolymer surfactant P123 as structure directed agent respectively. The characterization results show that the mesoporous SiO2 sieve has larger specific area (789 m2/g) than SiO2 nanoparticles (373 m2/g), and there exists a substantial difference in the N2 adsorption curves between the two samples. A speculative scheme shows that the formation of bottleneck during the N2 adsorption process of mesoporous SiO2 sieve should be responsible for the phenomenon.