Nanostructured platinum alloys for use as catalyst materials
A series of binary and ternary Pt-alloys, that promote the important reactions for catalysis at an alloy surface; oxygen reduction, hydrogen oxidation, and hydrogen and oxygen evolution. The first two of these reactions are essential when applying the alloy for use in a PEMFC.
1. A platinum (Pt) metal containing alloy composition useful as a catalyst, comprising:
a film including a compound of Pt and at least one transition metal element A from group IVB or VB of the Periodic table, wherein:
a structure of the compound is single phase,
the compound comprises a Pt content of less than 50 Atomic percent (At. %),
the compound exhibits a reversible electrochemical activity having a durability, and
the reversible electrochemical activity and the durability are at least as high as the reversible electrochemical activity and durability, respectively, of a compound consisting essentially of Pt.
2. The composition of claim 1 , wherein the Pt-containing compound further comprises at least one transition metal B, thereby forming a Pt-B-A alloy.
3. The composition of claim 2 , wherein B comprises at least one element selected from the group consisting of Nickel, Cobalt, and Iron.
4. The composition of claim 3 , wherein A comprises Vanadium.
5. The composition of claim 3 , wherein A comprises Titanium.
6. The composition of claim 2 , wherein the compound comprises the Pt content of 33 At. %.
7. The composition of claim 6 , wherein B comprises Nickel and A comprises Vanadium.
8. The composition of claim 6 , wherein A comprises Titanium and B comprises Nickel.
9. The composition of claim 2 , wherein the Pt content is between 15 At. % and 40 At. %.
10. An electrochemical device comprising the composition of claim 9 as an anode, wherein:
the Pt content is 37 At. %,
the transition metal B is Nickel having a content of 43 At. %,
the transition metal element A is Vanadium having a content of 20 At. %, and
the compound has the formula Pt 37 Ni 43 V 20 .
11. An electrochemical device comprising the composition of claim 9 as a cathode, wherein:
the Pt content is 33 At. %,
the transition metal B is Nickel having a content of 44 At. %,
the transition metal A is Vanadium having a content of 23% At. %, and
the compound has the formula Pt 33 Ni 44 V 23 .
12. The composition of claim 2 , wherein the compound has the formula (Pt 100-x B x ) 100-y A y with 0≦x≦80 and 0.5≦y≦60.
13. The composition of claim 1 , wherein the compound comprises the Pt content of 37.5 or less At. %.
14. The composition of claim 1 , wherein the Pt-containing compound further comprises:
at least one transition metal B; and
at least one platinum group metal (PGM), thereby forming a Pt-PGM-B-A alloy, wherein the PGM element includes at least one of Palladium (Pd), Ruthenium (Ru), Rhodium (Rh), Rhenium (Re), Osmium (Os), and Iridium (Ir).
15. The composition of claim 1 , wherein the compound comprises the Pt content of at least 19.9 At. %.
16. The composition of claim 15 , wherein the Pt-containing compound further comprises at least one transition metal B.
17. The composition of claim 16 , wherein A comprises Vanadium and B comprises Nickel.
18. The composition of claim 16 , wherein A comprises Titanium and B comprises Nickel.
19. The composition of claim 1 , wherein the transition metal A has a content between 0.5 At. % and 60% At. %.
20. The composition of claim 19 , wherein A is Vanadium and B is Nickel.
21. The composition of claim 19 , wherein A is Titanium and B is Nickel.
22. The composition of claim 1 , wherein the film is on a carbon support.
23. An electrochemical cell comprising the compound of claim 1 as an anode, wherein the compound further comprises at least one transition metal B selected from the group consisting of Nickel, Cobalt, and Iron, thus forming a Pt-B-A alloy exhibiting a reversible hydrogen oxidation reaction with an activity at least as high as an anode consisting essentially of Pt.
24. The electrochemical cell of claim 23 , wherein the transition metal element A is Vanadium or Titanium and the transition metal B is Nickel.
25. An electrochemical cell comprising the compound of claim 1 as an anode, wherein the compound further comprises at least one transition metal B selected from the group consisting of Nickel, Cobalt, and Iron, thus forming a Pt-B-A alloy exhibiting a reversible methanol oxidation reaction with an activity at least as high as an anode consisting essentially of Pt or Pt-Ruthenium.