| 摘要 |
<p>A heat resistant noble metal catalyst having both superior heat resistant property and a remarkable high activity at any temperature ranges consisting of a composition having a formula A1-zCzBxDuA l 12-y-uO19- alpha , wherein A is at least one element selected from the group consisting of Ba, Ca and Sr, C is at least one element selected from the group consisting of K, Rb and rare earth elements, B is at least one element selected from the group consisting of Mn, Co, Fe, Ni, Cu and Cr, D is at least one element selected from the group consisting of Au, Ag and platinum group noble metals, z is a value in a range of 0-about 0.4, x is a value in a range of 0-about 4, y is a value in a range of x-2x, u is a value of not less than about 0.01, x+u is a value of not more than about 4, and alpha is a value which is determined by the values X, Y, Z and U of the respective elements A, C, B and D and the values of x, y, z and u and is expressed as alpha = 1 - 1/2{X - z(X-Y) + xZ + uU - 3y - 3u}. d</p> |
