Squaraine dye/Ti3C2Tx MXene organic-inorganic hybrids for photocatalytic hydrogen evolution

MXenes, a new family of 2D nanostructured materials , have been widely studied in the field of artificial photosynthesis due to their outstanding physicochemical properties. In this work, a series of 2,4-bis[4-( N , N -dibutylamino)phenyl] squaraine ( SQ ) derivatives with different number of hydroxyl groups were hybridized with Ti 3 C 2 T x MXene nanosheets , and the organic–inorganic hybrid photocatalysts were applied for water-splitting hydrogen evolution . The mass ratios of SQ @Ti 3 C 2 T x were optimized to 4 wt% for each SQ , and the best hydrogen evolution reaction (HER) rate of 28.6 μmol h −1 g −1 was achieved by SQ-3 with four OH groups. The photocatalytic ability of the hybrid comes from the outstanding light harvesting of SQ dye, sufficient active sites of Ti 3 C 2 T x , and efficient separation and transfer of the photogenerated charges via heterojunction between SQ aggregates and Ti 3 C 2 T x . This work firstly demonstrates an example of SQ sensitizer combined with MXene for hydrogen generation, which provides a new insight to further explore the MXene-based hybrid nanomaterials for water splitting hydrogen evolution.