Self-photoreduced Ag0-doped Ag(I)-organic frameworks with efficient visible-light-driven photocatalytic performance

To investigate the facile synthesis strategy for MOF-based plasomic photocatalyst, an Ag(I)-organic framework [Ag3(psa)(4,4’-bpy)3]·OH·2CH3OH·2H2O (JLNU-91) was prepared by employing phenylsuccinic acid (H2psa) and 4,4’-bipyridine (4,4’-bpy) under room temperature. With irradiation of UV light, the partial separated Ag(I) sites in the framework can be reduced to metallic Ag0, producing a series of Ag0-doped JLNU-91/x. The photocatalytic experiments indicate that JLNU-91/x samples display improved photocatalytic activities for the degradation of methyl orange (MO) and the optimal JLNU-91/1 has 2.2 times higher degradation kinetic than pure JLNU-91. The photocurrent responses and EIS plots demonstrate that the SPR effect of self-reduced Ag0 promotes the separation of photoinduced electron-hole pairs. Moreover, the electron spin resonance (ESR) spectra and capture experiments reveal that the O2-, ·OH and holes play important roles in the photodegradation of MO. This work brings a new insight into the development of MOF-based plasmonic photocatalysts.