Synthesis of cobalt loaded double perovskite Sr ₂ TiFeO _{6 ‐δ} ( STF ) as a stable catalyst for enhanced hydrogen production via methane decomposition

Abstract

In this study, cobalt (Co) loaded Sr 2 TiFeO 6-δ (STF) double perovskite was synthesized using a modified nitrate combustion method for the application in catalytic decomposition of methane (CH 4 ) for hydrogen (H 2 ) production in a fixed bed reactor. The physicochemical properties of the catalyst were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energydispersive X-ray spectroscopy, N 2 adsorption-desorption, thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy. The catalyst showed a stable crystalline behavior with a uniform dispersion of Co over STF. The different compositions with varying Co loading were tested for methane decomposition at 850 C and constant flow rate. The 5% Co/STF achieving a maximum CH 4 conversion of ~95% with an H 2 yield of ~49%. Five percentage Co/STF showed excellent catalytic activity and stability for 46.5 hours time on stream without any indication of performance degradation. The spent catalyst was also analyzed using XRD, SEM, and TGA. The carbon deposited is shaped as carbon nanotubes that are a byproduct and also assist in metal exsolution in high-temperature processes. The use of STF shows the excellent potential showed by perovskites, which are stable in reducing environments, as support materials for methane decomposition.