Improved photocatalytic degradation of formaldehyde at room temperature using La doped ZnMn2O4

High indoor formaldehyde levels from residential decorations pose a pressing environmental concern, underscoring the urgency for effective catalytic degradation strategies. In this study, a La-doped ZnMn 2 O 4 catalyst with an oxygen-rich vacancy was successfully synthesized via a straightforward hydrothermal method. The experimental findings demonstrate that the L 0.5 ZMO catalyst, with a La doping amount of 0.5 mmol, exhibits a remarkable 100 % efficiency in degrading formaldehyde. Structural and spectroscopic analyses reveal that La doping in ZnMn 2 O 4 induces significant lattice expansion and an increased proportion of Mn 3 + species, both of which synergistically enhance the catalytic oxidation performance at room temperature. DFT results show that La doping concentrates the charge density near the Fermi energy level, significantly altering the charge distribution. This facilitates electron transfer, leading to enhanced photocatalytic performance. Furthermore, the introduction of oxygen vacancies generates abundant active sites, substantially improving the formaldehyde decomposition efficiency. This study highlights the critical role of La incorporation in modulating oxygen vacancies and surface properties of ZnMn 2 O 4 , yielding a cost-effective catalyst for efficient indoor formaldehyde abatement under ambient conditions.