Lamellar Co3O4/NH2-MIL125 composites: boosting photocatalytic activity and stability for toluene degradation

The removal of volatile organic compounds has been a long-standing challenge, and NH2-MIL125, with its large specific surface area, has shown great promise in this regard. However, its limited number of active sites hinders its widespread application. To address this limitation, we report the successful synthesis of a series of Co3O4-modified NH2-MIL125 metal-organic framework (MOF) composites with a lamellar structure. Notably, the optimized 35% Co3O4/NH2-MIL125 composite exhibited exceptional performance, achieving 85.59% degradation and 76.58% CO2 conversion under simulated sunlight. Moreover, this composite demonstrated excellent stability, maintaining a degradation rate of 79.67% over 520 min. The enhanced performance is attributed to the large specific surface area of NH2-MIL125, as well as the Co3O4 modification, which provides new active sites, enhances light utilization efficiency, accelerates the separation of photogenerated carriers, and facilitates the generation of reactive radicals. This in-situ growth strategy for modifying NH2-MIL125 with Co3O4 offers a novel approach to expand the application scope of NH2-MIL125 and enhance its performance in toluene degradation.Graphical abstract Characterization of layered Co3O4-modified NH2-MIL125 catalysts, evaluation of photocatalytic degradation performance of toluene, photogenerated carrier migration, and separation studies.