One-pot solvothermal synthesis of In-doped amino-functionalized UiO-66 Zr-MOFs with enhanced ligand-to-metal charge transfer for efficient visible-light-driven CO2 reduction

Metal organic frameworks (MOFs) with high porosity and highly tunable physical/chemical properties can serve as heterogeneous catalysts for CO2 photoreduction, but the application is hindered by the large band gap (Eg) and insufficient ligand-to-metal charge transfer (LMCT). In this study, a simple one-pot solvothermal strategy is proposed to prepare an amino-functionalized MOF (aU(Zr/In)) featuring an amino-functionalizing ligand linker and In-doped Zr-oxo clusters, which enables efficient CO2 reduction driven with visible light. The amino func-tionalization leads to a significant reduction of Eg as well as a charge redistribution of the framework, allowing the absorption of visible light and the efficient separation of photogenerated carriers. Furthermore, the incor-poration of In not only promotes the LMCT process by creating oxygen vacancies in Zr-oxo clusters, but also greatly lowers the energy barrier of the intermediates for CO2-to-CO conversion. With the synergistic effects of the amino groups and the In dopants, the optimized aU(Zr/In) exhibits a CO production rate of 37.58 +/- 1.06

Automated summary

In this study, a simple solvothermal strategy was proposed to prepare an amino-functionalized MOF (aU(Zr/In)) with highly tunable physical/chemical properties. The incorporation of amino functionalization and In doping led to efficient CO2 reduction driven with visible light, through the reduction of band gap and charge redistribution. The optimized aU(Zr/In) exhibited a CO production rate of 37.58 +/- 1.06.