A mesoporous material is a material containing pores with diameters between 2 and 50 nm, according to IUPAC nomenclature. For comparison, IUPAC defines microporous material as a material having pores smaller than 2 nm in diameter and macroporous material as a material having pores larger than 50 nm in diameter. SMB is a mesoporous material, molecular functions can be introduced into the pore surface, the fluid dynamic movement of molecules is advantageous, and the nanometal is encapsulated in the pore.