Exhaust treatment devices, catalyst, and methods of making and using the same
View Patent ↗In one embodiment, an exhaust treatment device includes: a substrate, a shell disposed around the substrate, and a retention material disposed between the shell and the substrate. The substrate includes a catalyst that includes a precious metal and a solid solution comprising solid solution metals, wherein the solid solution metals include yttrium, zirconium, and titanium.
1. A method of making a catalyst, the method comprising the steps of:
reacting a titanium salt with an alcohol to form a titanium alkoxide; and separately reacting a zirconium salt with an alcohol to form a zirconium alkoxide; followed by
mixing the titanium alkoxide and the zirconium alkoxide in the presence of an organic acid to form an organometallic precursor; followed by
decomposing the organometallic precursor to form a solid solution characterized by a zirconium-titanium oxide; and then
adding a precious metal to the solid solution to form the catalyst.
2. The method of claim 1 , wherein the solid solution further comprises yttrium and lanthanum.
3. The method of claim 1 , wherein forming the organometallic precursor further comprises:
reacting a yttrium salt with an alcohol to form a yttrium alkoxide;
reacting a lanthanum salt with an alcohol to form a lanthanum alkoxide; and
mixing the titanium alkoxide, the zirconium alkoxide, lanthanum alkoxide, and yttrium alkoxide to form the organometallic precursor.
4. The method of claim 1 , wherein decomposing the organometallic precursor to form a solid solution further comprises adding water to the organometallic precursor.
5. The method of claim 1 , wherein the organometallic precursor further comprises methacrylic acid.
6. The method of claim 1 , wherein the organometallic precursor comprises Zr 2 Ti 4 O 4 [OCH 2 CH 2 CH 2 CH 3 ][OC(O)CH 3 CH 2 ] 10 .
7. The method of claim 1 , wherein the organometallic precursor comprises a precious metal precursor.
8. The method of claim 1 , further comprising heat treating the catalyst to a temperature of greater than or equal to about 700° C.