Sugarcane Bagasse Hydrolysis by Metal Ions Mediated Synthesis of Perovskite LaCoO3 and the Photocatalytic Performance for Hydrogen from Formaldehyde Solution under Visible Light

Perovskite LaCoO3 was successfully synthesized using natural sugarcane bagasse with tunable oxygen vacancy. The preparation process was studied to elucidate the interaction between sugarcane bagasse and metal ions. And the prepared catalysts were characterized by XRD, SEM, XPS, DRS, and PL. The results indicated that bagasse was partly hydrolyzed by metal nitrate solution, and the gel was formed by adsorption and complexation between rich organic groups and metal ions, differing from citric acid complexation with metal ions. The bagasse fragments mediation in the process could modulate the amount of oxygen vacancy. An appropriate oxygen vacancy may act as the defect energy level above the valence band of LaCoO3 to adjust the band gap and accelerate charge transfer, resulting in high photocatalytic performance. Photocatalytic tests in formaldehyde aqueous solution under visible light demonstrated that LaCoO3 prepared by sugarcane bagasse exhibited higher hydrogen production than that prepared by conventional citric acid method.