Catalyst
Catalyst comprising a first layer having an outer layer with a layer comprising Pt directly thereon, wherein the first layer has an average thickness in a range from 0.04 to 30 nanometers, and wherein the layer. Catalysts described herein are useful, for example, in fuel cell membrane electrode assemblies.
1. An article comprising nanostructured elements comprising microstructured whiskers having an outer surface having a catalyst thereon, the catalyst comprising a first layer comprising a first material, wherein the first material comprises at least one of Ti, Hf, or Zr, the first layer having an outer layer with a layer comprising Pt directly thereon, wherein the first layer has an average thickness in a range from 0.04 to 30 nanometers, wherein the layer comprising Pt has an average thickness in a range from 0.04 to 50 nanometers, wherein the Pt and the at least one of Ti, Hf, or Zr collectively are present in an atomic ratio range from 0.01:1 to 10:1, and wherein the first material further comprises at least one of Ni, Co, Fe, Mn, Ir, or Pt.
2. The article of claim 1 , wherein the catalyst surface area is at least 5 percent greater than would be present without the presence of the first layer.
3. The article of claim 1 , wherein the catalyst further comprises at least one pair of alternating layers, wherein a first alternating layer comprises the first material, and wherein a second alternating layer comprises Pt.
4. A method of making the article of claim 1 , the method comprising depositing onto the outer surface of the microstructured whiskers any of the catalyst layers via a deposition technique independently selected from the group consisting of sputtering, atomic layer deposition, metal organic chemical vapor deposition, molecular beam epitaxy, ion soft landing, thermal physical vapor deposition, vacuum deposition by electrospray ionization, and pulse laser deposition.
5. The article of claim 1 , wherein the first material further comprises at least one of O, N, or C.
6. The article of claim 5 , wherein the catalyst surface area is at least 5 percent greater than would be present without the presence of the first layer.
7. The article of claim 5 , wherein the catalyst further comprises at least one pair of alternating layers, wherein a first alternating layer comprises the first material, and wherein a second alternating layer comprises Pt.
8. A method of making the article of claim 5 , the method comprising depositing onto the outer surface of the microstructured whiskers any of the catalyst layers via a deposition technique independently selected from the group consisting of sputtering, atomic layer deposition, metal organic chemical vapor deposition, molecular beam epitaxy, ion soft landing, thermal physical vapor deposition, vacuum deposition by electrospray ionization, and pulse laser deposition.
9. An article comprising nanostructured elements comprising microstructured whiskers having an outer surface having a catalyst thereon, the catalyst comprising a first layer comprising a first material, wherein the first material comprises at least one of Ti, Hf, or Zr, the first layer having an outer layer with a layer comprising Pt directly thereon, wherein the first layer has an average thickness in a range from 0.04 to 30 nanometers, wherein the layer comprising Pt has an average thickness in a range from 0.04 to 50 nanometers, wherein the Pt and the at least one of Ti, Hf, or Zr collectively are present in an atomic ratio range from 0.01:1 to 10:1, and wherein the catalyst further comprises at least one pair of alternating layers, wherein a first alternating layer comprises the first material, and wherein a second alternating layer comprises Pt.
10. An article comprising nanostructured elements comprising microstructured whiskers having an outer surface having a catalyst thereon, the catalyst comprising a first layer comprising a first material, wherein the first material comprises at least one of Ti, Hf, or Zr, the first layer having an outer layer with a layer comprising Pt directly thereon, wherein the first layer has an average thickness in a range from 0.04 to 30 nanometers, wherein the layer comprising Pt has an average thickness in a range from 0.04 to 50 nanometers, wherein the Pt and the at least one of Ti, Hf, or Zr collectively are present in an atomic ratio range from 0.01:1 to 10:1, wherein the first material further comprises at least one of O, N, or C, and wherein the catalyst further comprises at least one pair of alternating layers, wherein a first alternating layer comprises the first material, and wherein a second alternating layer comprises Pt.