Eosin Y bidentately bridged on UiO-66-NH₂ by solvothermal treatment towards enhanced visible-light-driven photocatalytic H₂ production

The coupling modes of dyes with corresponding supports play key roles in the performance of dye-sensitized heterogeneous photocatalytic systems. Herein, a solvothermal method was developed to synthesize a typical kind of dye-sensitized metal-organic frameworks (MOFs), Eosin Y (EY)-sensitized UiO-66-NH₂, in which EY was anchored on UiO-66-NH₂ via the bidentately bridging configuration of Zr⟵O-C = O→Zr. Such a coupling mode of chemical bonding strengthened the linking between EY and UiO-66-NH₂, increased the content of EY on UiO-66-NH₂, and facilitated the transfer of photogenerated electrons from EY to UiO-66-NH₂. Correspondingly, the H₂ evolution rate of EY-sensitized UiO-66-NH₂ via solvothermal treatment (2760 μmol g⁻¹ h^-1) was 8 times as that via room-temperature sensitization, with apparent quantum efficiency (AQE) ∼17.6 % at 500 nm. The as-obtained AQE and excellent stability performance exceeds most dye-sensitized photocatalytic systems for H₂ production. This work provides valuable information about developing dye-based or MOFs-based materials for efficient photocatalytic application.