Enhanced catalytic activity of perovskite oxide nanofibers for combustion of methane in coal mine ventilation air

Abstract

Methane in coal mine ventilation air is a major source of green house gases. The best way to abate its environmental impact is to combust it at moderate temperature. In this work, several oxide nanofibers with perovskite crystal structures, including LaCoO₃, LaMnO₃, LaFeO₃, La_0.8Sr_0.2CoO₃ and La_0.9Ce_0.1CoO₃, were fabricated by an electrospinning method followed by moderate temperature treatment. The as-prepared nanofibers were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermal gravimetric and differential thermal analysis, Fourier transform infrared spectroscopy, and a N₂ adsorption–desorption method. The results indicated that the pure perovskite oxide nanofibers with high surface areas were formed after 350 °C treatment for 1 h. The perovskite oxide nanofibers exhibited high catalytic activities for the combustion of methane in coal mine ventilation air. 100% methane conversion was reached at a moderate temperature of 470 °C due to the large surface area and porous structure of the La_0.8Sr_0.2CoO₃ perovskite nanofibers.