Manganese Oxide Decorated Co Nanoparticles on CaTiO3 for Higher Alcohols Synthesis from Syngas

Higher alcohols synthesis from syngas remains challenging, especially in balancing dissociative adsorption and associative adsorption sites. In this study, we prepared CaTi_0.7-xCo_0.3Mn_xO₃ (x = 0–0.4) catalysts with perovskite structure to enhance alcohol products selectivity. After reduction, metallic cobalt and manganese oxide uniformly dispersed on the perovskite’s surface. Upon introducing the reaction gases, MnO_x partially migrated onto the surface of the Co, reducing Co⁰ sites and facilitating electrons transfer from Co to Mn, which decreased the dissociative adsorption active sites for hydrocarbons and promoted the formation of Co₂C active sites. Adjusting the Mn doping allowed control over the Co₂C to Co ratio, thereby regulating associative adsorption and dissociative adsorption sites for CO. The manganese oxide layer can also prevent cobalt deactivation due to sintering. The CaTi_0.4Co_0.3Mn_0.3O₃ catalyst exhibited the best performance, achieving total alcohols selectivity of 38.6% at 270 °C, with higher alcohols constituting 70.0wt.% of them.