Ag/Mg-Al-O composite was prepared by the calcination of Ag-containing Mg-Al hydrotalcite-like compound and metallic Ag supported on periclase phase Mg-Al-O was obtained. The as-prepared Ag/Mg-Al-O composite exhibits good NOx storage capability in a relatively low temperature range of 150―300 °C. The highest NOx storage capability of 7.3 mg/g was achieved at 150 °C, while a lower NOx storage capability of 5.1 mg/g was achieved at 300 °C. Meanwhile, ca. 25% of NOx was observed to decompose to N2 at 300 °C. In situ FTIR results suggest that NOx mainly stored in Ag/Mg-Al-O catalyst in the form of bridging nitrites located on periclase phase Mg-Al-O.
