Gradient Polarization Induces Three‐Dimensional Asymmetric Electron Distribution in Covalent Organic Frameworks for Dramatically Enhanced Photocatalytic Overall Nitrogen Fixation

Abstract Constructing a donor–acceptor (D‐A)‐based covalent organic frameworks (COFs) is an effective approach to enhance photocatalytic efficiency, yet the spatial conformation imposes inherent trade‐offs between in‐plane and interplane carrier transport. Here, we present a spatial gradient polarization strategy that combines distinct electronegativities of (NH) 2 ─C═S and C═O groups in COFs to establish a 3D asymmetric electron distribution and the gradient polarization. Mechanistic studies have shown that the gradient polarization triggers the interlayer dipole rearrangement in a nonpolar orientation, thereby constructing a cooperative in‐plane and out‐of‐plane polarization field. This polarization field decouples the constraints on carrier transport and drives rapid charge transfer in an anisotropic manner, breaking the traditional perception of D‐A intramolecular polarization within the plane. Moreover, the resulting polarized microenvironment activates N≡N bonds, optimizes hydrogen‐bond networks, and stabilizes reaction intermediates, enabling the sequential conversion pathway of nitrogen. Ultimately, the covalent organic framework containing (NH) 2 ─C═S and C═O groups (SBO) exhibited excellent photocatalytic performance with yields of NH 4 + and NO 3 − of 11.59 and 7.18 mg g −1 h −1 , surpassing all reported systems. Additionally, under natural sunlight, SBO also achieves unprecedented NH 4 + (87.17 mg m −2 h −1 ) and NO 3 − (73.63 mg m −2 h −1 ) yields. Our research not only offers a strategic blueprint for modulating the 3D polarization in COFs but also bridges the gap in the relationship between the molecular structure of materials and the spatial carrier migration.