Hierarchical pore enhanced adsorption and photocatalytic performance of graphene oxide/Ti-based metal-organic framework hybrid for toluene removal

Metal-organic frameworks (MOFs) have been intensively hybridized with graphene oxide (GO) to enhance their catalytic performance; however, the effect of the pore structure of MOFs on the activity of GO/MOF hybrids remains elusive. Herein, GO nanosheets were integrated with Ti-based MOF (MIL-125) that possesses the controlled pore structure. The toluene removal experiment results demonstrate that hierarchically porous MIL-125 (MIL-125 (H)) with 10 wt% GO (10% GO/MIL-125 (H)) exhibits concurrent enhancement of adsorption and photocatalytic performance compared to these of 10 wt% GO/microporous MIL-125 (MIL-125 (M)) (10% GO/MIL-125 (M)) counterpart. It is because the hierarchical pore structure of MIL-125 (H) endows hybrids with faster mass diffusion, stronger interaction between components, easier charge separation, better light adsorption ability, and superior photothermal effect. This work provides a reference for the relationship between the pore structure of MOFs and the efficiency of GO/MOF hybrids. • The adsorption and photocatalytic performance of GO/MIL-125 hybrids are simultaneously enhanced by hierarchical pore. • The defective hierarchical pore in MIL-125 (H) assists to strengthen the interaction between GO and MIL-125 (H). • The photothermal effect of GO was improved by the hierarchical pore of MIL-125 (H).