Enhanced charge transfer for efficient photocatalytic H2 evolution over UiO-66-NH2 with annealed Ti3C2Tx MXenes.

Abstract The annealed Ti 3 C 2 T x MXenes retained original layered morphology and gave rise to the formation of TiO 2 is anticipated to achieve improved photocatalytic hydrogen evolution performance as a noble-metal-free co-catalyst. In this work, a novel Ti 3 C 2 /TiO 2 /UiO-66-NH 2 hybrid was rationally designed for the first time by simply introducing annealed Ti 3 C 2 T x MXenes over water-stable Zr-MOFs (UiO-66-NH 2) precursors via a facile hydrothermal process. As expected, the rationally designed Ti 3 C 2 /TiO 2 /UiO-66-NH 2 displayed significantly improvement in photocatalytic H 2 performance (1980 μmol·h−1·g−1) than pristine UiO-66-NH 2 under simulated sunlight irradiation. The excellent photocatalytic HER activity can be attributed to the formation of multi-interfaces in Ti 3 C 2 /TiO 2 /UiO-66-NH 2 , including Ti 3 C 2 /TiO 2 /UiO-66-NH 2 , Ti 3 C 2 /TiO 2 and Ti 3 C 2 /UiO-66-NH 2 interfaces, which constructed multiple pathways at the interfaces with Schottky junctions to accelerate the separation and transfer of charge carriers and endowed the accumulation of photo-generated electrons on the surface of Ti 3 C 2. This work expanded the possibility of porous MOFs for the development of efficient photocatalytic water splitting using annealed MXenes. Graphical abstract Image 1 Highlights • Ti 3 C 2 /TiO 2 /UiO-66-NH 2 was obtained by introducing annealed Ti 3 C 2 T x over Zr-MOFs. • Ti 3 C 2 /TiO 2 /UiO-66-NH 2 presented superior photocatlytic H 2 -production activity. • Three types of contact interfaces with Schottky junctions were depicted. • The enhanced charge transfer efficiency was investigated in detail. [ABSTRACT FROM AUTHOR]