Transient‐State Self‐Bipolarized Organic Frameworks of Single Aromatic Units for Natural Sunlight‐Driven Photosynthesis of H₂O₂

Abstract

Constructing π‐conjugated polymer structures through covalent bonds dominates the design of organic framework photocatalysts, which significantly depends on the selection of multiple donor‐acceptor building blocks to narrow the optical gap and increase the lifetimes of charge carriers. In this work, self‐bipolarized organic frameworks of single aromatic units are demonstrated as novel broad‐spectrum‐responsive photocatalysts for H2O2 production. The preparation of such photocatalysts is only to fix the aromatic units (such as 1,3,5‐triphenylbenzene) with alkane linkers in 3D space. Self‐bipolarized aromatic units can drive the H2O2 production from H2O and O2 under natural sunlight, wide pH ranges (3.0‐10.0) and natural water sources. Moreover, it can be extended to catalyze the oxidative coupling of amines. Experimental and theoretical investigation demonstrate that such a strategy obeys the mechanism of through‐space π‐conjugation, where the closely face‐to‐face overlapped aromatic rings permit the electron and energy transfer through the large‐area delocalization of the electron cloud under visible light irradiation. This work introduces a novel design concept for the development of organic photocatalysts, which will break the restriction of conventional through‐band π‐conjugation structure and will open a new way in the synthesis of organic photocatalysts.

Triazine Ring-Enhanced Transient-State Self-Bipolarized Organic Frameworks for Natural Sunlight-Driven H2O2 Photosynthesis

“…This poses increasingly higher demands on the monomer design and synthesis control. Very recently, we developed a strategy to construct organic photocatalysts with single aromatic units . The face-to-face overlapped aromatic units could be transient-state self-bipolarized (TSB) under light irradiation and drive H 2 O 2 production from H 2 O and O 2 even under natural sunlight.…”