Hereafter, the pore-enlarged samples optimized are designated as MS-m and MSb, respectively. Nitrogen adsorption isotherms of the mesoporous silica MS, MS-m, and MS-b are shown in Fig. 1A, with all samples exhibiting type IV isotherms in the IUPAC classification with hysteresis loops. The corresponding pore size distribution curves are shown in Fig. 1B, and indicate a rather broad distribution of mesopores in a range of 10–120 nm.