摘要 |
<p>Methods of forming a silica-based products are disclosed. One method comprises: (a) providing a silica containing precursor (SCP) contained in solution that has a pH less than or equal to a pH of 7; (b) optionally doping the SCP with one or more metal species, wherein said doping occurs when the solution has a pH less than or equal to a pH of 7; (c) adjusting the pH of the solution to greater than 7; (d) adding an effective amount of salt to the solution so that the conductivity of the solution is greater than or equal to 4 mS, wherein said addition occurs prior to, simultaneous with, or after the pH adjustment in step 1c; (e) optionally filtering and drying the SCP; and (f) optionally reacting the dried product from step e with a functional group and optionally wherein the resultant functionalized dried product is at least one of the following: a functionalized metal oxide-doped or metal sulfide-doped silica product. Another method comprises: (a) providing a silica containing precursor (SCP) contained in solution that has a pH greater than 7; (b) adjusting the pH of the solution to less than or equal to 7; (c) optionally doping the SCP with one or more metal species, wherein said doping occurs when the solution has a pH less than or equal to a pH of 7; (d) adjusting the pH of the solution to greater than 7; (e) adding an effective amount of salt to the solution so that the conductivity of the solution is greater than or equal to 4 mS, wherein said addition occurs prior to, simultaneous with, or after the pH adjustment in step 2d; (f) optionally filtering and drying the SCP; and (g) optionally reacting the dried product from step f with a functional group and optionally wherein the resultant functionalized dried product is at least one of the following: a functionalized metal oxide-doped or metal sulfide-doped silica product.</p> |