High porosity metal oxide catalyst coatings
Disclosed in certain implementations is a catalysis composition that includes a metal catalyst and a support material impregnated with the metal catalyst.
1. A catalysis composition comprising:
a manganese oxide catalyst, wherein at least 50% of the manganese oxide catalyst is in amorphous form; and
a support material impregnated with the manganese oxide catalyst,
wherein an average pore radius of the catalysis composition is from about 6 nanometers to about 15 nanometers, a cumulative pore volume of the catalysis composition is from about 0.80 mL/g to about 2 mL/g, and a surface area of the catalysis composition is from about 100 m 2 /g to about 200 m 2 /g,
wherein the catalysis composition, when coated onto an automobile radiator and contacted with an airstream having an initial ozone concentration, is adapted to convert ozone within the airstream such that a final ozone concentration of the airstream is reduced by greater than 30% of the initial ozone concentration after the catalysis composition is contacted with the airstream,
wherein the support material is selected from the group consisting of ceria, lanthana, alumina, titania, silica, zirconia, carbons, metal organic framework, clay, zeolites, and combinations thereof,
wherein the manganese oxide catalyst is impregnated in the support material in an amount ranging from about 10% to about 25% manganese atoms by mass, based on the total composition, and
wherein at least about 15% of a total number of manganese atoms in the manganese oxide catalyst are dispersed within about 10 nanometers of an outer surface of the catalyst composition as detectable by surface X-ray photoelectron spectroscopy (XPS).
2. The catalysis composition of claim 1 , wherein the cumulative pore volume of the catalysis composition is from about 0.85 mL/g to about 2 mL/g.
3. The catalysis composition of claim 1 , wherein the support material comprises alumina.
4. The catalysis composition of claim 1 , wherein the manganese oxide catalyst comprises at least one of Mn 3 O 4 crystallites or MnO crystallites.
5. The catalysis composition of claim 1 , wherein an x-ray diffraction spectrum of the catalysis composition comprises at least one characteristic peak comprising at least one of a manganosite peak, pyrolusite peak, a bixbyite peak, or a hausmannite peak.
6. The catalysis composition of claim 1 , wherein the manganese oxide catalyst is impregnated in the support material in an amount ranging from about 10% to about 20% manganese atoms by mass, based on the total catalysis composition.
7. The catalysis composition of claim 1 , further comprising:
a first binder; and
a second binder.
8. The catalysis composition of claim 7 , wherein the first binder is a styrene acrylic binder having a first glass transition temperature ranging from about 5° C. to about 20° C., and wherein the second binder is a styrene acrylic binder having a second glass transition temperature that is greater than the first glass transition temperature.
9. The catalysis composition of claim 7 , wherein the first binder is a styrene acrylic binder having a first glass transition temperature ranging from about 70° C. to about 90° C., and wherein the second binder is a styrene acrylic binder having a second glass transition temperature that is less than the first glass transition temperature.
10. The catalysis composition of claim 7 , wherein the first binder is a styrene acrylic binder having a first glass transition temperature ranging from about 5° C. to about 20° C., and wherein the second binder is a styrene acrylic binder having a second glass transition temperature ranging from about 70° C. to about 90° C.
11. The catalysis composition of claim 1 , wherein, after coating the catalysis composition onto a substrate, an ultrasonic washcoat adhesion weight loss of the substrate is less than 1.60%.
12. The catalysis composition of claim 1 , wherein a surface area of the catalysis composition is from about 160 m 2 /g to about 200 m 2 /g.
13. The catalysis composition of claim 1 , wherein the catalysis composition, when coated onto an automobile radiator and contacted with the airstream, exhibits a deactivation factor of at least 0.6, wherein the deactivation factor is the ratio of aged catalyst % ozone conversion to fresh catalyst % ozone conversion, wherein the aged % conversion is after exposure of the coated radiator to the equivalent of 150,000 miles driving time.
14. The catalysis composition of claim 13 , wherein the deactivation factor is at least 0.7.
15. The catalysis composition of claim 14 , wherein the manganese oxide catalyst is impregnated in the support material in an amount ranging from about 10% to about 20% manganese atoms by mass, based on the total composition.
16. The catalysis composition of claim 13 , wherein the manganese oxide catalyst is impregnated in the support material in an amount ranging from about 10% to about 20% manganese atoms by mass, based on the total composition.
17. The catalysis composition of claim 13 , where the deactivation factor is at least 0.65.
18. The catalysis composition of claim 17 , wherein the manganese oxide catalyst is impregnated in the support material in an amount ranging from about 10% to about 20% manganese atoms by mass, based on the total composition.
19. The catalysis composition of claim 1 , wherein the support material is selected from a group consisting of alumina, silica, and combinations thereof.
20. The catalysis composition of claim 1 further comprising an over layer on the support material and the manganese oxide catalyst, wherein the over layer comprises at least one of a protective coat, an adhesion coat, or an additional catalysis coat.
21. The catalysis composition of claim 1 , wherein an average primary crystallite dimension of the plurality of crystallite domains is less than 100 nanometers.
22. The catalysis composition of claim 1 , wherein the initial ozone concentration ranges from about 0.1 ppm to about 1.2 ppm, the space velocity of the airstream ranges from about 200,000 hr −1 to about 800,000 hr −1 and the temperature of the airstream is maintained within a range of about 70° C. to about 80° C.
23. A catalysis device comprising:
an automobile radiator; and
the catalysis composition of claim 1 , wherein the catalysis composition is coated onto the automobile radiator.