Exhaust gas purification catalyst

Abstract

To provide an exhaust gas purification catalyst that has superior exhaust gas purification performance compared to conventional exhaust gas purification catalysts, while also being inexpensive and cost-effective. [Solution] An exhaust gas purification catalyst comprising an alloy containing a first metal element and a second metal element, wherein the first metal element is a noble metal element, the second metal element is a base metal transition element, and the alloy forms a solid solution in any temperature range of 100°C to 1000°C. Preferably, the alloy forms a solid solution in any temperature range of 100°C to 1000°C in a total composition ratio independent of the composition ratio of the first metal element and the second metal element.

Claims

1. An exhaust gas purification catalyst comprising an alloy containing a primary metal element and a secondary metal element, The aforementioned first metallic element is a noble metallic element, The aforementioned second metallic element is a base metal transition metal element, The aforementioned alloy forms a solid solution in a temperature range of 100°C to 1000°C, and is an exhaust gas purification catalyst.

2. The exhaust gas purification catalyst according to claim 1, wherein the alloy forms a solid solution in a total composition ratio independent of the composition ratio of the first metal element and the second metal element at any temperature in the range of 100°C to 1000°C.

3. The exhaust gas purification catalyst according to claim 1 or 2, wherein the alloy is a PdCo alloy, a RhNi alloy, a PdNi alloy, or an AuNi alloy.

4. The exhaust gas purification catalyst according to claim 1 or 2, wherein the surface elemental composition ratio of the first metal element in the alloy, as measured by X-ray photoelectron spectroscopy, is 3% to 99%.

5. The exhaust gas purification catalyst according to claim 4, wherein the surface elemental composition ratio of the first metal element in the alloy, as measured by X-ray photoelectron spectroscopy, is 5% to 99%.

6. The exhaust gas purification catalyst according to claim 4, wherein the surface elemental composition ratio of the first metal element in the alloy, as measured by X-ray photoelectron spectroscopy, is 3% to 17%.

7. The exhaust gas purification catalyst according to claim 6, wherein the surface element composition ratio of the first metal element in the alloy, as determined by X-ray photoelectron spectroscopy, is 7% to 17%.

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