Construction of an amino-rich Ni/Ti bimetallic MOF composite with expanded light absorption and enhanced carrier separation for efficient photocatalytic H2 evolution

Metal organic framework (MOF) materials are a multi-component system integrating light harvesting and catalysis for photocatalytic hydrogen production, which is of great importance for sustainable development. In present work, Ni nanoparticles were first prepared by a chemical reduction method, and then an amino-rich Ni/Ti bimetallic MOF composite was synthesized by a one-pot method. The introduction of Ni leads to the rearrangement in electronic structure and thus to reduced charge recombination in the MOFs. The introduction of amino group as a photosensitizer expands the light absorption range. Thus, the absorption of NH 2 -MIL-125(Ti) after Ni modification extended from 473 to 624 nm, and the hydrogen evolution rate under visible light reached 699 μmol g −1 h −1 , which is about 9 times that of parent NH 2 -MIL-125(Ti). Ti-MOFs show a new design potential to integrate light harvesting and catalytic components for photocatalytic hydrogen production. • An amino-rich Ni/Ti bimetallic MOF composite is synthesized. • The introduction of Ni to enhance charge separation and transfer in the MOFs. • The amino group as a photosensitizer expands the light absorption range of MOFs. • The hydrogen evolution rate of NH 2 -MIL-125-Ni 10% /Ti is 9 times that of NH 2 -MIL-125.