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

A species of novel Sr-doped rare earth double perovskite catalysts (La2–xSrxNiAlO6, 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), H2-temperature-programmed reduction (H2-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 La1.9Sr0.1NiAlO6 catalyst exhibited significantly improved catalytic activity (T10=378.7 °C, T90=602.9 °C) compared with that of La2NiAlO6, whose T10 decreased by 74.4 °C and T90 decreased by 66.8 °C, respectively. The excellent catalytic activity of La1.9Sr0.1NiAlO6 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.

Graphical AbstractCatalytic performance of La2NiAlO6 and La1.9Sr0.1NiAlO6 catalysts; Saturation magnetization curves of La2NiAlO6 and La1.9Sr0.1NiAlO6 catalystsFigure optionsDownload full-size imageDownload as PowerPoint slide