Dramatically Enhancing Multiphoton Harvesting Metal–Organic Frameworks for NIR-II Photocatalysis through Functional Regulation of Octupolar Molecules

The development of effective multiphoton absorption (MPA) materials for near-infrared (NIR) light-driven photocatalysis holds great significance. In this study, we incorporated two multibranched cyclometallated iridium(III) modules with varying degrees of conjugation onto MPA-inert metal-organic frameworks (MOFs) to active MPA performance. Subsequently, the MOFs were further modified with Co(II) and hyaluronic acid (HA) to fabricate <b>MINCH</b> and <b>MISCH</b>, respectively. By introducing octupolar molecules and expanding the conjugation, <b>MISCH</b> exhibited a larger MPA cross section for efficient NIR light absorption and improved carrier transfer, leading to outstanding NIR light-driven multiphoton photocatalytic hydrogen production. Moreover, the HA modification enabled <b>MISCH</b> to achieve specific multiphoton photocatalytic hydrogen therapy for cancer cells. This study provides valuable insights into constructing highly active MPA materials for NIR light-driven photocatalysis, presenting a potential platform for hydrogen therapy in tumor treatment.