Synthesis of a SiO2 nanofibre confined Ni catalyst by electrospinning for the CO2 reforming of methane

A silica (SiO2) nanofibre confined nickel (Ni) catalyst was successfully synthesized by the electrospinning technique and was then systematically characterized with thermogravimetric/differential thermal analysis (TG/DTA), X-ray photoelectron spectroscopy (XPS), N-2 sorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution-transmission electron microscopy (HR-TEM), temperature-programmed oxidation (O-2-TPO), temperature-programmed reduction (H-2-TPR) and temperature-programmed desorption (CO2-TPD) measurements. In the electrospinning synthesized Ni/SiO2 catalyst, most of the Ni nanoparticles were confined inside SiO2 nanofibers with an average particle size of 8.1 nm. Compared with the Ni/SiO2 catalyst conventionally prepared via the incipient impregnation method using commercial SiO2 powder as the support, the electrospun Ni/SiO2 catalyst exhibited improved metal dispersion and enhanced metal-support interaction, leading to slightly higher activity and much better stability in the carbon dioxide (CO2) reforming of methane. Carbon deposition, rather than metal sintering, is identified as the main cause for the deactivation of the Ni/SiO2 catalyst under current conditions. The present work demonstrates that electrospinning is a potential technique for the fabrication of nanoconfined catalysts with superior catalytic performance and macro-scale handling properties.