Interfacial charge regulation on porphyrin copper metal-organic frameworks /BiVO4 S-scheme nanocomposites for CO2 photoreduction in pure water

The construction of S-scheme heterojunction is an effective approach to achieve high-efficiency photocatalytic conversion, where efficient interfacial charge transfer plays a crucial role. Herein, two-dimensional reduced graphene oxide (rGO) modulated porphyrin copper metal–organic frameworks/BiVO 4 (Cu-MOF/rGO/BVO) S-scheme nanocomposites with wide visible-light response are manufactured for photoreduction CO 2 . The optimized one exhibits approximately 13-fold photoactivity improvement compared with the pristine BVO nanosheets in pure water system. The high photoactivity is mainly ascribed to the S-scheme charge transfer between Cu-MOF and BVO and accelerated interfacial charge transfer modulated by rGO. The introduced rGO is capable of not only forming strong chemical interactions with both Cu-MOF and BVO, but also providing “highway” for electrons transfer, efficiently strengthening the S-scheme charge transfer. Moreover, it is revealed that the porous structure and well-defined Cu 2 (COO) 4 node of Cu-MOF creates a microenvironment conducive to CO 2 activation mainly based on electrochemical reduction measurement, in situ diffuse reflectance infrared spectra and density functional theory. This work highlights the importance of interfacial charge regulation for constructing S-scheme heterojunction and presents a feasible avenue for efficient conversion of solar-to-fuels.