Nickel Glyoximate Based Metal-Covalent Organic Frameworks for Efficient Photocatalytic Hydrogen Evolution

Metal-covalent organic frameworks (MCOFs) have been recently received wide attention owing to the homogeneous distribution of active metal centers that are beneficial for enhancing the application potentials. However, metal complex based functional building blocks for MCOFs synthesis are limited. Herein, two new MCOFs (Ni-Py-COF and Ni-Bn-COF) were constructed via a novel nickel glyoximate based building block. Splendid photocatalytic activity on hydrogen evolution from water and great long-term recyclability were achieved using these nickel glyoximate based MCOFs as photocatalysts. Excitingly, even without the addition of Pt co-catalyst, the hydrogen evolution rates (HER) of Ni-Py-COF reached up to 626 mu mol g(-1) h(-1), which is better than many porous organic polymers. This work not only expands the type of building units for MCOFs, but also provides meaningful insights for developing stable, efficient and earth-abundant photocatalysts toward H-2 generation.

Automated summary

Metal-covalent organic frameworks (MCOFs) have gained significant attention for their homogeneous distribution of metal centers, which enhances their potential applications. In this study, two new MCOFs were successfully constructed using a novel building block based on nickel glyoximate. These MCOFs showed excellent photocatalytic activity and long-term recyclability for hydrogen evolution from water. Furthermore, one of the MCOFs achieved high hydrogen evolution rates without the addition of a co-catalyst, outperforming many porous organic polymers.