Catalyst for solid polymer fuel cells and method for producing same

Patent metadata

Field	Value
Publication number	US-2016013495-A1
Application number	US-201414766236-A
Country	US
Kind code	A1
Filing date	Feb 12, 2014
Priority date	Feb 15, 2013
Publication date	Jan 14, 2016
Grant date	—

Abstract

Provided is a catalyst for solid polymer fuel cell that exhibits excellent initial activity and favorable durability and a method for manufacturing the same. The invention is a catalyst for solid polymer fuel cell which is formed by supporting catalyst particles including platinum, cobalt and manganese on a carbon powder carrier, wherein a composition ratio (molar ratio) among platinum, cobalt and manganese in the catalyst particles is Pt:Co:Mn=1:0.06 to 0.39:0.04 to 0.33, a peak intensity ratio of a Co—Mn alloy appearing in the vicinity of 2θ=27° is 0.15 or less with respect to a main peak appearing in the vicinity of 2θ=40° in X-ray diffraction analysis of the catalyst particles, and a fluorine compound having a C—F bond is supported at least on the surface of the catalyst particles. The amount of the fluorine compound supported is preferably from 3 to 20% with respect to the entire mass of the catalyst.

First claim

1 . A catalyst for solid polymer fuel cell having catalyst particles comprising platinum, cobalt and manganese supported on a carbon powder carrier, wherein
a composition ratio (molar ratio) among platinum, cobalt and manganese in the catalyst particles is Pt:Co:Mn=1:0.06 to 0.39:0.04 to 0.33,
a peak intensity ratio of a Co—Mn alloy appearing in the vicinity of 2θ=27° is 0.15 or less with respect to a main peak appearing in the vicinity of 2θ=40° in X-ray diffraction analysis of the catalyst particles, and
a fluorine compound having a C—F bond is supported at least on a surface of the catalyst particles.

2 . The catalyst for solid polymer fuel cell according to claim 1 , wherein the fluorine compound is supported from 3 to 20% by mass with respect to the entire mass of the catalyst.

3 . The catalyst for solid polymer fuel cell according to claim 1 , wherein the fluorine compound is a fluorine resin or a fluorine-based surface active agent.

4 . The catalyst for solid polymer fuel cell according to claim 1 , wherein a peak ratio of a CoPt 3 alloy and a peak ratio of a MnPt 3 alloy appearing in the vicinity of 2θ=32° are 0.13 or more with respect to a main peak appearing in the vicinity of 2θ=40° in X-ray diffraction analysis of the catalyst particles.

5 . The catalyst for solid polymer fuel cell according to claim 1 , wherein a supporting density of the catalyst particles is from 30 to 70%.

6 . A method for manufacturing a catalyst for solid polymer fuel cell, the catalyst defined in claim 1 , comprising the steps of:
supporting cobalt and manganese on a platinum catalyst having platinum particles supported on a carbon powder carrier; subjecting the platinum catalyst that is formed by the supporting step and supports cobalt and manganese to a heat treatment at from 700 to 1100° C.; and forming a water-repellent layer including a fluorine compound on the catalyst by bringing the catalyst after the heat treatment step into contact with a solution containing the fluorine compound.

7 . The method for manufacturing a catalyst for solid polymer fuel cell according to claim 6 , comprising the step of:
eluting cobalt and manganese on the surface of the catalyst particles by bringing the catalyst after the heat treatment into contact with an oxidizing solution at least one time.

8 . The method for manufacturing a catalyst for solid polymer fuel cell according to claim 7 , wherein the oxidizing solution is sulfuric acid, nitric acid, phosphorous acid, potassium permanganate, hydrogen peroxide, hydrochloric acid, chloric acid, hypochlorous acid and chromic acid.

9 . The method for manufacturing a catalyst for solid polymer fuel cell according to claim 7 , wherein a contact treatment with the oxidizing solution is conducted at a treatment temperature of from 40 to 90° C. for a contact time of from 1 to 10 hours.

10 . The catalyst for solid polymer fuel cell according to claim 2 , wherein the fluorine compound is a fluorine resin or a fluorine-based surface active agent.

11 . The catalyst for solid polymer fuel cell according to claim 2 , wherein a peak ratio of a CoPt 3 alloy and a peak ratio of a MnPt 3 alloy appearing in the vicinity of 2θ=32° are 0.13 or more with respect to a main peak appearing in the vicinity of 2θ=40° in X-ray diffraction analysis of the catalyst particles.

12 . The catalyst for solid polymer fuel cell according to claim 3 , wherein a peak ratio of a CoPt 3 alloy and a peak ratio of a MnPt 3 alloy appearing in the vicinity of 2θ=32° are 0.13 or more with respect to a main peak appearing in the vicinity of 2θ=40° in X-ray diffraction analysis of the catalyst particles.

13 . The catalyst for solid polymer fuel cell according to claim 2 , wherein a supporting density of the catalyst particles is from 30 to 70%.

14 . The catalyst for solid polymer fuel cell according to claim 3 , wherein a supporting density of the catalyst particles is from 30 to 70%.

15 . The catalyst for solid polymer fuel cell according to claim 4 , wherein a supporting density of the catalyst particles is from 30 to 70%.

16 . A method for manufacturing a catalyst for solid polymer fuel cell, the catalyst defined in claim 2 , comprising the steps of:
supporting cobalt and manganese on a platinum catalyst having platinum particles supported on a carbon powder carrier; subjecting the platinum catalyst that is formed by the supporting step and supports cobalt and manganese to a heat treatment at from 700 to 1100° C.; and forming a water-repellent layer including a fluorine compound on the catalyst by bringing the catalyst after the heat treatment step into contact with a solution containing the fluorine compound.

17 . A method for manufacturing a catalyst for solid polymer fuel cell, the catalyst defined in claim 3 , comprising the steps of:
supporting cobalt and manganese on a platinum catalyst having platinum particles supported on a carbon powder carrier; subjecting the platinum catalyst that is formed by the supporting step and supports cobalt and manganese to a heat treatment at from 700 to 1100° C.; and forming a water-repellent layer including a fluorine compound on the catalyst by bringing the catalyst after the heat treatment step into contact with a solution containing the fluorine compound.

18 . A method for manufacturing a catalyst for solid polymer fuel cell, the catalyst defined in claim 4 , comprising the steps of:
supporting cobalt and manganese on a platinum catalyst having platinum particles supported on a carbon powder carrier; subjecting the platinum catalyst that is formed by the supporting step and supports cobalt and manganese to a heat treatment at from 700 to 1100° C.; and forming a water-repellent layer including a fluorine compound on the catalyst by bringing the catalyst after the heat treatment step into contact with a solution containing the fluorine compound.

19 . A method for manufacturing a catalyst for solid polymer fuel cell, the catalyst defined in claim 5 , comprising the steps of:
supporting cobalt and manganese on a platinum catalyst having platinum particles supported on a carbon powder carrier; subjecting the platinum catalyst that is formed by the supporting step and supports cobalt and manganese to a heat treatment at from 700 to 1100° C.; and forming a water-repellent layer including a fluorine compound on the catalyst by bringing the catalyst after the heat treatment step into contact with a solution containing the fluorine compound.

20 . The method for manufacturing a catalyst for solid polymer fuel cell according to claim 8 , wherein a contact treatment with the oxidizing solution is conducted at a treatment temperature of from 40 to 90° C. for a contact time of from 1 to 10 hours.

Assignees

• Tanaka Precious Metal Ind

Inventors

• Ishida Minoru
• Nakajima Hitoshi
• Matsutani Koichi

Classifications

• H01M4/926 Primary

  on carbon or graphite · CPC title

• H01M4/8842

  Coating using a catalyst salt precursor in solution followed by evaporation and reduction of the precursor · CPC title

• H01M4/8882

  Heat treatment, e.g. drying, baking · CPC title

• H01M4/8892

  Impregnation or coating of the catalyst layer, e.g. by an ionomer · CPC title

• H01M4/921

  Alloys or mixtures with metallic elements · CPC title