Noble Metal‐Free Photosensitive Terpyridine Coordination Assemblies for Efficient Single‐Molecule H ₂ O ₂ Photocatalysis

Abstract Conventional molecular photocatalysts characterized by long‐lived excited states, such as Ru and Ir complexes are widely recognized and used in photocatalysis. However, developing new heavy atom‐free photosensitive coordination complexes by manipulating their molecular structures to achieve highly efficient photocatalytic reactions remains challenging. In this study, a series of novel terpyridine complexes, S1 – S4 , with a rigid donor–acceptor configuration was designed and synthesized via precise heteroleptic, coordination‐driven self‐assembly. Experimental data, combined with theoretical calculations, confirmed that long‐lived charge‐transfer excited states were generated, enabling excellent photosensitivity. Furthermore, high‐efficiency photocatalytic total synthesis of H 2 O 2 was achieved in pure water under an air atmosphere via a synergetic process of energy transfer and electron transfer to form 1 O 2 and •O 2 – , respectively, in these complexes, differing significantly from previous reports on polymer catalysts. Notably, complex S1 exhibited an outstanding photocatalytic H 2 O 2 production rate of 10 mmol g −1 h −1 , outperforming most organic photocatalytic systems. In addition, S1 achieved a photocatalytic rate of up to 40 mmol g −1 h −1 and a solar‐to‐chemical conversion of 1.23% with the sacrificial agent. This study not only paves the way for the development of novel noble metal‐free photocatalysts but also introduces a novel photocatalytic paradigm for the green and high‐performance synthesis of H 2 O 2 .