Effect of cerium ions on the activity of La1-x,CexSrNiO4 (0 <= x <= 0.3) for NO decomposition was investigated both in the absence and presence of oxygen. The amount of Ce in the frame reached 30at.% (x = 0.3) in the present case without destroying the matrix structure. The Ce-substituted samples showed high activity for NO decomposition not only in the absence of O-2 but also in the presence of 02, and the specific activity reached 1.59 mu mol s(-1) m(-2) even 6.0%O-2 was fed to the reactant gas (La0.7Ce0.3SrNiO4, T = 1123 K), indicating that the Ce addition can enhance the oxygen forbearance of catalyst. In addition, a new highly active site, which facilitates oxygen mobilization and desorption, might be formed in the sample due to the Ce addition, which thus resulted in the high activity for NO decomposition. (c) 2005 Elsevier B.V All rights reserved.