Catalyst layer supported on substrate hairs of metal oxides
In one embodiment, a catalyst assembly includes a substrate including a substrate base and a number of substrate hairs extending longitudinally from the substrate base, the substrate base including a metal M, the number of substrate hairs including an oxide of the metal M; and a catalyst film contacting at least a portion of the substrate.
1. A catalyst assembly comprising:
a substrate including a substrate base and a number of substrate hairs extending longitudinally from the substrate base, the substrate base including a metal M, the number of substrate hairs including an oxide of the metal M and spaced apart from each other with an average distance of 10 to 500 nanometers; and
a catalyst film contacting at least a portion of the substrate.
2. The catalyst assembly of claim 1 , wherein the substrate hairs have an average thickness dimension of 10 to 200 nanometers.
3. The catalyst assembly of claim 1 , wherein the substrate hairs have an average length dimension of 0.05 to 20 micrometers.
4. The catalyst assembly of claim 1 , wherein the metal oxide is of an amount of 90 weight percent based on total weight of the substrate hairs.
5. A catalyst assembly comprising:
a substrate including a substrate base and a number of substrate hairs extending from the substrate base, the substrate base including a metal M, the number of substrate hairs including an oxide of the metal M; and
a catalyst film contacting at least a portion of the substrate, wherein the substrate base includes a plurality of first and second spaced apart strands extending in first and second directions, respectively, to form a mesh with openings each bonded by an adjacent pair of the first spaced apart strands and an adjacent pair of the second spaced apart strands, the number of substrate hairs extending from at least one of the first and second spaced apart strands.
6. A catalyst assembly comprising:
a substrate including a substrate base and a number of substrate hairs extending from the substrate base, the substrate base including a metal M, the number of substrate hairs including an oxide of the metal M; and
a catalyst film contacting at least a portion of the substrate, wherein the substrate base includes a number of discontinuous, spaced apart areas, the number of substrate hairs contacting at least one of the number of spaced apart areas.
7. A catalyst assembly comprising:
a substrate including a substrate base and a number of substrate hairs extending from the substrate base, the substrate base including a metal M, the number of substrate hairs including an oxide of the metal M; and
a catalyst film contacting at least a portion of the substrate, the catalyst film includes a first catalyst atomic layer, a second exposed catalyst atomic layer, and a number of intermediate catalyst atomic layers between the first and second catalyst atomic layers, wherein the total number of the catalyst atomic layers is 2 to 20 atomic layers.
8. A method of forming a catalyst assembly, comprising;
oxidizing a substrate base including the metal M, in the presence of a humidifying gas flow, to form an oxide of the metal M as a number of substrate hairs extending from the substrate base; and
depositing a catalyst film onto the substrate base and the number of substrate hairs.
9. The method of claim 8 , wherein a first portion of the substrate is oxidized in the oxidizing step, thereby leaving an unoxidized portion of the substrate base forming the substrate base.
10. The method of claim 8 , wherein the humidifying gas flow includes at least one of oxygen, nitrogen and carbon dioxide.
11. The method of claim 8 , further comprising humidifying a gas flow to form the humidifying gas flow.
12. The method of claim 11 , wherein the humidifying step is carried out before the oxidizing step.
13. The catalyst assembly of claim 5 , wherein the substrate hairs have an average thickness dimension of 10 to 200 nanometers.
14. The catalyst assembly of claim 5 , wherein the metal oxide is of an amount of 90 weight percent based on total weight of the substrate hairs.
15. The catalyst assembly of claim 6 , wherein the metal oxide is of an amount of 90 weight percent based on total weight of the substrate hairs.
16. The catalyst assembly of claim 7 , wherein the metal oxide is of an amount of 90 weight percent based on total weight of the substrate hairs.
17. The catalyst assembly of claim 7 , wherein the substrate hairs have an average length dimension of 0.05 to 20 micrometers.