Non-noble metal based electro-catalyst compositions for proton exchange membrane based water electrolysis and methods of making

• US 10,435,803 B2
• Filed: 07/11/2018
• Issued: 10/08/2019
• Est. Priority Date: 08/08/2012
• Status: Active Grant

• Current Assignee: University of Pittsburgh of The Commonwealth System of Higher Education
• Original Assignee: University of Pittsburgh of The Commonwealth System of Higher Education
• Inventors: Kumta, Prashant N., Kadakia, Karan Sandeep, Datta, Moni Kanchan, Velikokhatnyi, Oleg, Hanumantha, Prashanth Jampani
• Primary Examiner(s): Soliman, Haytham
• Application Number:
  US16/032,139
• Publication Number:
  US 20180320278A1
• Time in Patent Office: 454 Days
• Field of Search: 502325
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C25B 1/04 by electrolysis of water
• CPC Class Codes: C25B 11/051 Electrodes formed of electrocatalysts on a substrate or carrier
• CPC Class Codes: C25B 11/093 at least one noble metal or noble metal oxide and at least one non-noble metal oxide
• CPC Class Codes: C25B 9/73 of the filter-press type
• CPC Class Codes: H01M 4/881 Electrolytic membranes
• CPC Class Codes: H01M 4/8828 Coating with slurry or ink
• CPC Class Codes: H01M 4/9016 Oxides, hydroxides or oxygenated metallic salts
• CPC Class Codes: H01M 4/9075 Catalytic material supported on carriers, e.g. powder carriers H01M4/8807, H01M4/881, H01M4/8814, H01M4/925 take precedence
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

The invention provides electro-catalyst compositions for an anode electrode of an acid mediated proton exchange membrane-based water electrolysis system. The compositions include a noble metal component selected from the group consisting of iridium oxide, ruthenium oxide, rhenium oxide and mixtures thereof, and a non-noble metal component selected from the group consisting of tantalum oxide, tin oxide, niobium oxide, titanium oxide, tungsten oxide, molybdenum oxide, yttrium oxide, scandium oxide, cooper oxide, zirconium oxide, nickel oxide and mixtures thereof. Further, the non-noble metal component can include a dopant. The dopant can be at least one element selected from Groups III, V, VI and VII of the Periodic Table. The compositions can be prepared using any solution based methods involving a surfactant approach or a sol gel approach. Further, the compositions are prepared using noble metal and non-noble metal precursors. Furthermore, a thin film containing the compositions can be deposited onto a substrate to form the anode electrode.

Claims

1. An electro-catalyst composition for an anode electrode of a proton exchange membrane-based water electrolysis system, comprising:

a noble metal component of iridium oxide;

a non-noble metal component selected from the group consisting of tantalum oxide, tin oxide, niobium oxide, titanium oxide, tungsten oxide, molybdenum oxide, yttrium oxide, scandium oxide, copper oxide, zirconium oxide, nickel oxide and mixtures thereof;

optionally, a dopant; and

the electro-catalyst composition having one of the following general formulas;

Ir_1-2xSn_xM_xO₂ and Ir_1-2xSn_xM_xO₂;

D,

wherein M represents Nb, Ta, Ti, W, Mo, Y, Sc, Cu, Zr, Ni and mixtures thereof, D represents at least one element of Groups III, V, VI and VII of the Periodic Table, and x is a value from greater than 0 to 49.5% based on weight of the composition,

wherein the electro-catalyst composition is in a form selected from an oxide alloy and a solid solution, and

wherein the electro-catalyst composition exhibits an electronic structure that mimics a noble metal oxide electro-catalyst composition absent of a non-noble metal.

2. The composition of claim 1, wherein the dopant is selected from the group consisting of fluorine, chlorine, bromine, iodine, sulfur, selenium, tellurium and mixtures thereof.

3. The composition of claim 1, wherein the dopant is present in an amount from greater than 0 to 20 weight percent based on weight of the composition.

4. The composition of claim 1, wherein the non-noble metal component and the noble metal component form a complete solid solution.

5. The composition of claim 1, wherein the composition is in the form of a nanocrystalline thin film, nanorods, nanoplates, nanoshells, nanoflakes, nanorods, nanospheres, or any nano-scale morphology coated on a current collector substrate.