Regulating the Donor and Acceptor Interaction Mode in Metal-Organic Frameworks for H₂O₂ Photosynthesis

Development of novel photocatalysts for hydrogen peroxide (H₂O₂) production from water and oxygen is gathering great attention, but still suffers from inefficient photogenerated charge mobility. Reticular chemistry in metal-organic frameworks (MOFs) provides a promising platform to enhance the charge-transfer kinetics by assembling a donor-acceptor (D-A) system. Here, we designed and synthesized a series of D-A type MOFs (UiO-67-NB, UiO-67-PE/BB, and UiO-67-PE/NB) via regulating the interaction mode of donor and acceptor. As the first example of short and long-range combined D-A MOF, UiO-67-PE/NB exerted enhanced photogenerated electron transfer as well as suppressed their backward recombination, which facilitated the indirect two-step 2e^- ORR for visible-light driven photosynthesis of H₂O₂, with a remarkable production rate of 5141 μmol h^-1 g^-1, superior to that of short-range UiO-67-NB (813 μmol h^-1 g^-1) and long-range UiO-67-PE/BB (3361 μmol h^-1 g^-1), and also exceeding most of MOF-based photocatalysts. This work puts forward new insights into systematic engineering of D-A MOFs at the molecular level for highly efficient H₂O₂ photosynthesis.