Acidic bimetallic LaCo-MOF materials showing synergistic catalytic effect on the air epoxidation of cyclooctene

•The introduction of the La element changes the morphology and structure of the bimetallic La2Co8-MOF-BTC-H material significantly.•The binding energies of bimetallic elements in La2Co8-MOF-BTC-H material have obvious changes, indicating that Co and La have obvious interaction in the coordination structure.•Compared with the single-metallic MOF material, the acidity of the bimetallic La2Co8-MOF-H material is significantly enhanced, favorable for the epoxidation of cyclooctene.•Under optimal conditions, the conversion of cyclooctene and the selectivity of epoxy compounds can reach 96.2% and 98.7%.•The activity of the La2Co8-MOF-BTC-H material does not decrease significantly after 5 times repeated-use, indicative of its recyclable stability.