Optimizing Light Dynamics: Designing a Ni-MOF Functionalized g-CN Type II Heterostructure and a TiC MXene Schottky Junction for the Efficient Photocatalytic H Production.

The photocatalytic production of hydrogen (H) from water is a vital avenue towards sustainable energy and addressing global environmental challenges. To maximize efficiency, harnessing the synergistic effects of multiple co-catalysts is essential, as these interactions can significantly enhance performance. In this study, we introduce a ternary heterojunction composed of a nickel-imidazole framework (Ni-MOF), graphitic carbon nitride (CN), and TiC MXene (TC), employing solvothermal and wet impregnation methods, featuring a well-designed Type II heterojunction and a noble metal-free Schottky junction for efficient hydrogen evolution. The Type II heterojunction between Ni-MOF and CN minimizes charge carrier recombination and promotes photogenerated electron generation, while TC as an electron acceptor enhances electron capture, increases participation in surface reactions, and augments active sites. Consequently, the Ni-MOF/CN/TC hybrid catalyst achieves outstanding photocatalytic hydrogen evolution under visible light, with a peak production rate of 1044.46 μmol/g over 3 hours, surpassing CN by 13 fold and Ni-MOF/CN by 50 %. This work provides insights into MXene-based ternary systems, emphasizing the potential for enhanced light absorption and efficient charge separation, making it a promising platform for photocatalytic applications.