Highly active, robust and versatile multifunctional, fully non-noble metals based electro-catalyst compositions and methods of making for energy conversion and storage

Patent metadata

Field	Value
Publication number	US-2018331369-A1
Application number	US-201615776092-A
Country	US
Kind code	A1
Filing date	Dec 12, 2016
Priority date	Dec 10, 2015
Publication date	Nov 15, 2018
Grant date	—

Abstract

The invention provides noble metal-free electro-catalyst compositions for use in acidic media, e.g., acidic electrolyte. The noble metal-free electro-catalyst compositions include non-noble metal absent of noble metal. The non-noble metal is non-noble metal oxide, and typically in the form of any configuration of a solid or hollow nano-material, e.g., nano-particles, a nanocrystalline thin film, nanorods, nanoshells, nanoflakes, nanotubes, nanoplates, nanospheres and nanowhiskers or combinations of myriad nanoscale architecture embodiments. Optionally, the noble metal-free electro-catalyst compositions include dopant, such as, but not limited to halogen. Acidic media includes oxygen reduction reaction (ORR) in proton exchange membrane (PEM) fuel cells, and direct methanol fuel cells and oxygen evolution reaction (OER) in PEM-based water electrolysis and metal air batteries, and hydrogen generation from solar energy and electricity-driven water splitting.

First claim

1 . A noble metal-free electro-catalyst composition for use in acidic media, comprising:
a non-noble metal selected from the group consisting of manganese oxide, titanium oxide, vanadium oxide, iron oxide, chromium oxide, tantalum oxide, tin oxide, niobium oxide, tungsten oxide, molybdenum oxide, yttrium oxide, scandium oxide, copper oxide, zinc oxide, cobalt oxide, nickel oxide, lanthanum oxide, cerium oxide, neodymium oxide, erbium oxide, gadolinium oxide, ytterbium oxide and mixtures thereof, wherein, the noble metal-free electro-catalyst is absent of any noble metal.

2 . The composition of claim 1 , further comprising a dopant selected from the group consisting of at least one element from Groups III, V, VI and VII of the Periodic Table.

3 . The composition of claim 1 , having a general formula I:
( a x b y )O z :wc   (I)
wherein, a is Mn, Cu, Zn, Sc, Fe, Co, Ti, V, Ni, Cr, Ta, Sn, Nb, W, Mo, Y, La, Ce, Nd, Er, Gd, Yb or mixtures thereof; b is Mn; O is oxygen; c is F, Cl, Br, I, S, Se, Te, N, P, As, Sb, Bi, Al, B or mixtures thereof; x and y are each a number greater than or equal to 0 and less than or equal to 2, x and y being the same or different, when x=0, y is a number greater than 0 and less than or equal to 2 and when y=0, x is a number greater than 0 and less than or equal to 2; z is a number that is greater than 0 and less than or equal to 4, and w is from 0% by weight to about 20% by weight, based on total weight of the composition.

4 . The composition of claim 2 , wherein the dopant is selected from the group consisting of fluorine, chlorine, bromine, iodine, sulfur, selenium, tellurium, nitrogen, phosphorus, arsenic, antimony, bismuth, aluminum, boron and mixtures thereof.

5 . The composition of claim 2 , wherein the dopant is present in an amount from greater than 0 to about 20 weight percent based on total weight of the composition.

6 . The composition of claim 2 , wherein the dopant is present is an amount from about 10 to about 15 weight percent based on total weight of the composition.

7 . The composition of claim 1 , wherein the non-noble metal-based electro-catalyst is in the form selected from the group consisting of nano-particles, a nanocrystalline thin film, nanorods, nanoshells, nanoflakes, nanotubes, nanoplates, nanospheres, nanowhiskers or combinations thereof.

8 . The composition of claim 3 , wherein the non-noble metal is a binary metal oxide comprising copper oxide and manganese oxide, and the dopant is fluorine.

9 . The composition of claim 3 , wherein x is 1.5, y is 1.5, z is 4 and w is 0, 5, 10 and 15 percent by weight.

10 . The composition of claim 3 , wherein x is 1.5, y is 1.5, z is 2.75 and w is 1.25.

11 . The composition of claim 1 , wherein the acidic media is selected from the group consisting of oxygen reduction reaction in a proton exchange membrane fuel cell, direct methanol fuel cell and oxygen evolution reaction in a proton exchange membrane based water electrolysis.

12 . A method for preparing a noble metal-free electro-catalyst for an acidic electrolyte, comprising:
combining a non-noble metal oxide precursor with a precipitation or reaction agent to form a non-noble metal oxide precipitate; separating the precipitate; drying the precipitate; and forming a noble metal-free oxide powder.

13 . The method of claim 12 , further comprising introducing a dopant precursor prior to the step of drying the nanoparticles, to form a solid solution.

14 . The method of claim 12 , wherein the non-noble metal oxide precursor is manganese acetate tetrahydrate, the precipitation agent or reaction agent is potassium permanganate, the precipitate is manganese dioxide nanoparticles, the dopant precursor is ammonium fluoride, and the powder is fluorine-doped manganese oxide powder.

15 . The method of claim 12 , further comprising applying the electro-catalyst composition to a substrate to form an electrode.

Assignees

• Univ Pittsburgh Commonwealth Sys Higher Education

Inventors

• Kumta Prashant N
• Patel Prasad P
• Datta Moni K
• Velikokhatnyi Oleg
• Hanumantha Prashanth J
• Kuruba Ramalinga
• Ghadge Shrinath

Classifications

• H01M4/881

  Electrolytic membranes · CPC title

• H01M4/8825

  Methods for deposition of the catalytic active composition · CPC title

• H01M4/9016 Primary

  Oxides, hydroxides or oxygenated metallic salts · CPC title

• H01M8/08

  Fuel cells with aqueous electrolytes · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title