Effect of lanthanum and chlorine doping on strontium titanates for the electrocatalytically-assisted oxidative dehydrogenation of ethane

[Display omitted] •Ethylene was produced via electrocatalytically-assisted oxidative dehydrogenation of ethane.•O2− conducting membrane, YSZ and LSM-YSZ were used as electrolyte and cathode, respectively.•Strontium titanate-based perovskites showed promising results as anode catalysts.•Lanthanum doping improved the conductivity and increased the ethane conversion rates.•Chlorine incorporation to La-doped SrTiO3 increased the conversion and ethylene selectivity. Oxidative dehydrogenation (ODH) of alkanes is an important catalytic reaction that can be used to convert less valuable alkanes, such as ethane, to more valuable olefins, such as ethylene. However, further oxidation of olefins to carbon dioxide and carbon monoxide limits the selectivity of the process. Oxide ion-conducting electrolyte reactors allow for controlling oxygen availability to the reaction and thus, improve the selectivity for olefin formation. In this study, strontium titanate-type perovskites were tested as anode catalysts for electro ODH reaction. Cl-incorporated, La-doped strontium titanates were synthesized via a modified Pechini route. The effect of lanthanum doping and chlorine incorporation on these catalysts was investigated. The characteristics of the catalysts were examined using ambient and in-situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), temperature-programmed oxidation (TPO) using CO2, laser Raman spectroscopy, and electrical conductivity measurements. In addition, impedance measurements were also taken to better understand the cell characteristics and resistances. Electrocatalytically-assisted ODH tests on the cell with La0.2Sr0.8TiO3±dClσ anode showed that ethane conversion and ethylene production rates increase with increasing current. It was also observed that La doping increases the electrical conductivity and ethane conversion, while Cl doping increases both ethane conversion and ethylene selectivity.