Preparation of SiO
According to one inventive concept, a method for forming an aerogel includes forming a SiO 2 gel, forming a mixture of the SiO 2 gel and a TiCl 4 -derived precursor sol, wherein the TiCl 4 sol is comprised of TiCl 4 and a solvent, forming a SiO 2 /TiO 2 wet gel, drying the SiO 2 /TiO 2 wet gel, and heating the dried SiO 2 /TiO 2 gel.
1. A method of forming a SiO 2 —TiO 2 composite aerogel using epoxide-assisted gelation, the method comprising:
forming a SiO 2 aerogel;
forming a mixture of the SiO 2 aerogel and a TiCl 4 -derived precursor sol (TiCl 4 sol), wherein the TiCl 4 sol is comprised of TiCl 4 and a solvent, wherein the SiO 2 aerogel is in the form of SiO 2 aerogel particles,
forming a SiO 2 /TiO 2 wet gel, wherein an epoxide is added to the mixture of the SiO 2 aerogel particles and the TiCl 4 sol;
drying the SiO 2 /TiO 2 wet gel; and
heating the dried SiO 2 /TiO 2 gel thereby forming a SiO 2 /TiO 2 composite aerogel.
2. The method of claim 1 , wherein forming the SiO 2 aerogel comprises:
forming a SiO 2 wet gel;
drying the wet SiO 2 gel to form a SiO 2 aerogel; and
crushing the SiO 2 aerogel into a powder comprising the SiO 2 aerogel particles.
3. The method of claim 2 , wherein forming the SiO 2 —TiO 2 wet gel comprises adding epoxide to the mixture of the SiO 2 aerogel particles dispersed in the TiCl 4 sol for gelation of the mixture.
4. The method of claim 1 , wherein the formed aerogel is a SiO 2 —TiO 2 composite aerogel.
5. The method of claim 1 , wherein the solvent includes a mixture of dimethylformamide and water.
6. The method of claim 1 , wherein the drying comprises supercritical carbon dioxide drying.
7. The method of claim 1 , wherein the heating is at a temperature in a range of about 600° C. to about 1000° C.
8. The method of claim 1 , wherein the heating is at a temperature in a range of greater than 800° C. to about 1000° C.
9. The method of claim 1 , wherein the SiO 2 /TiO 2 composite aerogel is a SiO 2 @TiO 2 core-shell aerogel.