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CN-112786903-B - Conductive anti-corrosion magnesium-titanium oxide material

CN112786903BCN 112786903 BCN112786903 BCN 112786903BCN-112786903-B

Abstract

The invention relates to a conductive corrosion-resistant magnesium titanium oxide material. A fuel cell catalyst system comprising a catalyst and a catalyst support material that binds the catalyst and comprises a corrosion resistant conductive material having oxygen vacancies having formula (I): Where δ is any number from 0 to 3 representing an oxygen vacancy, optionally including a fractional portion, the material having a conductivity of about 2 to 10S/m at room temperature in the surrounding environment.

Inventors

  • S.JIN
  • CHENG LEI
  • J. Meloa
  • M. Cohen Bruce
  • N. Clegg
  • ZHANG DAWEI

Assignees

  • 罗伯特·博世有限公司

Dates

Publication Date
20260508
Application Date
20201105
Priority Date
20191106

Claims (15)

  1. 1. A fuel cell catalyst system comprising: catalyst, and A catalyst support material that binds the catalyst and comprises a corrosion resistant conductive non-stoichiometric material having oxygen vacancies having formula (I): Wherein the method comprises the steps of Delta is any number from 0 to 3 representing an oxygen vacancy, including a fractional portion, The non-stoichiometric material has a conductivity of 2-10S/m at room temperature in the surrounding environment.
  2. 2. The catalyst system of claim 1, wherein the static corrosion current density of the catalyst support material is less than 1 μΑ cm -2 at a temperature of 0-80 ℃ at pH 2.
  3. 3. The catalyst system of claim 1, wherein the non-stoichiometric material has a Mg/Ti ratio of a number in the range of 0.3-0.6.
  4. 4. The catalyst system of claim 1, wherein the catalyst is a redox reaction catalyst.
  5. 5. The catalyst system of claim 1, wherein the catalyst comprises at least some Pt (100) surface facets.
  6. 6. The catalyst system of claim 5, wherein the catalyst forms at least one island on the catalyst support material.
  7. 7. A corrosion resistant conductive non-stoichiometric material comprising: a metal oxide crystalline structure having oxygen vacancies having formula (I): Wherein delta is any number from 0 to 3 representing an oxygen vacancy, including a fractional portion, The non-stoichiometric material has a nominal chemical composition of 33 mole% MgO and 66 mole% TiO-TiO 2 mixture and an electrical conductivity of 2-10S/m at room temperature in the surrounding environment.
  8. 8. The material of claim 7, wherein the Mg/Ti ratio of the material is a number in the range of 0.3-0.6.
  9. 9. The material of claim 7, wherein the static etch current density of the material is less than 1 μΑ cm -2 at a temperature of 0-80 ℃ at pH 2.
  10. 10. The material of claim 7, wherein the material is a fuel cell catalyst support material.
  11. 11. A catalyst support comprising: a corrosion resistant conductive crystalline non-stoichiometric material having oxygen vacancies having formula (I): Wherein delta is any number from 0 to 3 representing an oxygen vacancy, including a fractional portion, The crystalline non-stoichiometric material has a conductivity of 2-10S/m at room temperature in the surrounding environment.
  12. 12. The catalyst support according to claim 11, wherein the catalyst is a cathode fuel cell catalyst.
  13. 13. The catalyst support of claim 11, wherein the non-stoichiometric material has a static corrosion current density of less than 1 μΑ cm -2 at a temperature of 0-80 ℃ at pH 2.
  14. 14. The catalyst support according to claim 11, wherein the Mg/Ti ratio of the non-stoichiometric material is a number in the range of 0.3-0.6.
  15. 15. The catalyst support of claim 11, wherein the non-stoichiometric material has an activation energy of 0.13 eV in the temperature range of 25 ̊ C-80 ̊ C.

Description

Conductive anti-corrosion magnesium-titanium oxide material Technical Field The present invention relates to corrosion resistant conductive magnesium titanium oxide materials having oxygen vacancies. Background Metals have become a widely used material for thousands of years. Various methods have been developed to protect metals and prevent them from corroding or decomposing into oxides, hydroxides, sulphates and other salts. Metals are particularly susceptible to corrosion in some industrial applications due to the aggressive working environment. Non-limiting examples may be metal components of a fuel cell, such as bipolar plates (BPP) or catalyst support materials of a fuel cell. In addition, certain components, such as BPP, need not only be sufficiently chemically inert to resist degradation in the highly corrosive environment of the fuel cell, but also need to be electrically conductive to facilitate electron transfer of the oxygen reduction reaction of the fuel cell. Finding a material that meets both of these requirements has been a challenge. Disclosure of Invention According to one embodiment, a fuel cell catalyst system is disclosed. The fuel cell catalyst system comprises a catalyst and a catalyst support material that binds the catalyst and comprises a corrosion resistant conductive material having oxygen vacancies having formula (I): Wherein δ is any number from 0 to 3 representing an oxygen vacancy, optionally including a fractional portion. The material may have a conductivity of about 2-10S/m at room temperature in the surrounding environment. The bipolar plate may have a static corrosion current density of less than about 1 μa cm -2 at a temperature of about 0-80 ℃ at a pH of 2. The Mg/Ti ratio of the material may be a number in the range of 0.3-0.6. Delta may include a fractional portion. The material may be non-stoichiometric. The catalyst may be a redox reaction catalyst. The catalyst may comprise at least some Pt (100) surface facets (facet). The catalyst may form at least one island on the catalyst support material. In an alternative embodiment, a corrosion resistant conductive material is disclosed. The corrosion resistant conductive material may comprise a metal oxide crystalline structure having oxygen vacancies having formula (I): Wherein δ is any number from 0 to 3, optionally including a fractional portion and representing an oxygen vacancy. The material may have a nominal chemical composition of about 33 mole% MgO and 66 mole% of a mixture of TiO and TiO 2. The Mg/Ti ratio may be a number in the range of 0.3 to 0.6. Delta may include a fractional portion. The bipolar plate may have a static corrosion current density of less than about 1 μa cm -2 at a temperature of about 0-80 ℃ at a pH of 2. The material may be a fuel cell catalyst support material. The material may be non-stoichiometric. In yet another embodiment, a catalyst support is disclosed. The catalyst support may comprise a corrosion resistant conductive crystalline material having oxygen vacancies having formula (I): wherein δ is any number from 0 to 3 representing an oxygen vacancy, optionally including a fractional portion. The crystalline material may have a conductivity of about 2-10S/m at room temperature in the ambient environment. The catalyst may be a cathode fuel cell catalyst. The bipolar plate may have a static corrosion current density of less than about 1 μa cm -2 at a temperature of about 0-80 ℃ at a pH of 2. The Mg/Ti ratio of the material may be a number in the range of 0.3-0.6. The material may have an activation energy of about 0.13 eV in the temperature range of 25 ℃ to 80 ℃. Delta may include a fractional portion. Drawings FIG. 1 depicts a schematic composition of a proton exchange membrane fuel cell including bipolar plates in accordance with one or more embodiments; FIG. 2 shows a perspective view of a non-limiting example of a bipolar plate having a body portion and a surface portion comprising a corrosion-resistant and electrically-conductive material, in accordance with one or more embodiments; FIG. 3 shows a non-limiting example of a synthetic pellet sample of the disclosed materials; FIGS. 4A and 4B show the structure of MgTi 2O5 indicating insulating behavior and the density of states (DOS) of MgTi 2O4.92 indicating conducting behavior, respectively; FIGS. 5A to 5E show the chemical structures of (110) MgTi 2O5、(110)MgTi2O5-δ、(101)TiO2 (anatase), (110) TiO 2 (rutile) and (001) TiO; FIG. 6 shows an Arrhenius plot of the conductivity of MgTi 2O5-δ from 25℃to 80 ℃; FIG. 7 shows the Ti 2p X ray photoelectron spectroscopy (XPS) spectra of the as-synthesized MgTi 2O5-δ、MgTi2O5-δ and TiO 2 after annealing in air; FIG. 8 is an X-ray diffraction (XRD) pattern of as-synthesized MgTi 2O5-δ vs. MgTi2O5; FIGS. 9A to 9C are photographs of MgTi 2O5-δ、MgTi2O5-δ as synthesized after annealing in air at 600℃and MgTi 2O5-δ after annealing in air at 1000 ℃; FIG. 10 shows a graph comparing corrosion current densi