Surface structure and catalytic performance of Sr-doped La2NiAlO6 double perovskite catalysts for methane combustion

Abstract A species of novel Sr-doped rare earth double perovskite catalysts (La 2– x Sr x NiAlO 6 , x =0, 0.1) were prepared by the sol-gel method using citric acid as a complexing agent and calcined at 1100 °C for 3 h, then investigated for methane catalytic combustion. The as-prepared catalysts were characterized by X-ray diffraction patterns (XRD), H 2 -temperature-programmed reduction (H 2 -TPR), specific surface area (BET), magnetic property measurement technology ( M-H ), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Experimental results showed that La 1.9 Sr 0.1 NiAlO 6 catalyst exhibited significantly improved catalytic activity ( T 10 =378.7 °C, T 90 =602.9 °C) compared with that of La 2 NiAlO 6 , whose T 10 decreased by 74.4 °C and T 90 decreased by 66.8 °C, respectively. The excellent catalytic activity of La 1.9 Sr 0.1 NiAlO 6 caused by Sr-doping could be explained by the larger number of adsorption oxygen on the catalyst surface, which could be proven by XPS analysis.