Photo-to-chemical energy conversion requires a systematic and complex molecular design to manage consecutive photochemical processes, including energy harvesting, exciton migration, electron transfer, charge separation, and charge transport. However, such an integrated design remains a substantial challenge. Here, we report a seamless system in managing these photochemical events on the basis of two-dimensional sp² carbon-conjugated covalent organic frameworks. The frameworks are designed to be fully π conjugated for harvesting a wide range of visible to near-infrared light and to constitute built-in donor-acceptor heterojunction interfaces for splitting excitons. The frameworks create dense yet ordered columnar π arrays that offer pathways to facilitate exciton migration and charge transport. Loading reaction centers in pores or on surface shortens the electron-transfer distance and promotes the accumulation of electrons at the reaction centers. These three molecular mechanisms are seamlessly integrated in the frameworks and render the system able to efficiently produce hydrogen that is driven by low-energy photons.

光化学能量转换需要系统且复杂的分子设计，以管理连续的光化学过程，包括能量收集，激子迁移，电子转移，电荷分离和电荷转移。但是，这样的集成设计仍然是一个巨大的挑战。在这里，我们报告了一个基于二维sp ²的无缝系统，用于管理这些光化学事件碳共轭共价有机骨架。框架被设计成完全π共轭的，以收集大范围的可见光至近红外光，并构成用于分裂激子的内置供体-受体异质结界面。框架创建密集但有序的柱状π阵列，这些阵列提供了促进激子迁移和电荷传输的途径。将反应中心负载在孔中或表面上会缩短电子转移距离，并促进电子在反应中心处的积累。这三种分子机制无缝集成在框架中，使系统能够有效产生由低能光子驱动的氢。