Preparation of a Novel Ternary Composite of TiO2/UiO-66-NH2/Graphene Oxide with Enhanced Photocatalytic Activities

Inhibiting the recombination of electron–hole pairs of TiO 2 -based photocatalysts to enhance the photocatalytic activities received continuous attention in the past decades. Herein, a ternary composite of TiO 2 /UiO-66-NH 2 /graphene oxide was designed to facilitate the photoelectrons transfer. When –NH 2 was grafted, graphene oxide was introduced by 0.05 g and Ti/Zr molar ratio of the composite was 19, the composite exhibited enhanced photocatalytic performance in a period of 45 min dye removing tests (degrading rate over 97%) and a significant improvement (H 2 evolution rate 0.27 mmol/h in 2 h) in hydrogen evolution tests. Furthermore, in the reversibility test, the composite could maintain high dye degrading efficiency (over 88%) after five cycles and the apparent quantum efficiency reach 8.04% in 12-h H 2 evolution test which means electron–holes recombination was efficiently inhibited and the structure of the composite was relatively stable. Graphical Abstract Schematic diagram of the enhanced photocatalytic mechanism over the ternary TiO 2 /UiO-66-NH 2 /GO composites.