Method of preparing metal oxide-silica composite aerogel and metal oxide-silica composite aerogel prepared by the same
Provided is a method of preparing a metal oxide-silica composite aerogel and a metal oxide-silica composite aerogel having an excellent weight reduction property prepared by the method. The method comprises adding an acid catalyst to a first water glass solution to prepare an acidic water glass solution (step 1); adding a metal ion solution to the acidic water glass solution to prepare a precursor solution (step 2); and adding a second water glass solution to the precursor solution and performing a gelation reaction (step 3).
1. A method of preparing a metal oxide-silica composite aerogel, the method comprising:
1) adding an acid catalyst to a first water glass solution to prepare an acidic water glass solution;
2) adding a metal ion solution to the acidic water glass solution to prepare a precursor solution; and
3) adding a second water glass solution to the precursor solution and performing a gelation reaction.
2. The method according to claim 1 , wherein a pH of the acidic water glass solution is 0.1 to 2.9.
3. The method according to claim 1 , wherein a reaction temperature while performing the gelation reaction is 10 to 100° C.
4. The method according to claim 1 , wherein a reaction temperature while performing a gelation reaction is 10 to 80° C.
5. The method according to claim 1 , wherein a concentration of the precursor solution is 0.1 to 3.9% by weight based on 1 L of a solvent.
6. The method according to claim 1 , wherein a concentration of the precursor solution is 0.1 to 3.0% by weight based on 1 L of a solvent.
7. The method according to claim 1 , wherein a concentration of the first water glass solution is 0.01 M to 2.0 M.
8. The method according to claim 1 , wherein a concentration of the metal ion solution is 0.01 M to 2.0 M.
9. The method according to claim 1 , wherein a concentration of the second water glass solution is 0.5 M to 6.0 M.
10. The method according to claim 1 , wherein a concentration of the second water glass solution is higher than a concentration of the first water glass solution.
11. The method according to claim 1 , wherein the second water glass solution is added that a pH of the precursor solution becomes 3 to 10.
12. The method according to claim 1 , wherein the metal ion solution comprises ions of one or more metals selected from the group consisting of alkali metals, alkaline earth metals, lanthanides, actinides, transition metals, and metals in Group 13 (IIIA).
13. The method according to claim 1 , wherein the metal ion solution is a binary metal ion solution comprising calcium ions (Ca 2+ ) and magnesium ions (Mg 2+ ).
14. The method according to claim 13 , wherein a molar ratio of the calcium ions (Ca 2+ ) to the magnesium ions (Mg 2+ ) in the metal ion solution is 1:1 to 1:20.
15. The method according to claim 1 , wherein the acid catalyst is one or more acids selected from the group consisting of hydrochloric acid, nitric acid, acetic acid, sulfuric acid, and hydrofluoric acid.
16. The method according to claim 1 , further comprising washing and drying after performing the gelation reaction.