关键词: 光催化析氧反应 ;聚苝酰亚胺 ;原子结构 ;电子结构, 反应路径

Abstract: Polymeric perylene diimide (PDI) has been evidenced as a good candidate for photocatalytic water oxidation, yet the origin of the photocatalytic oxygen evolution activity remains unclear and need further exploration. Herein, with crystal and atomic structures revealed from the X-ray diffraction pattern, the electronic structure is theoretically illustrated by the first-principles density functional theory calculations, suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution. It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal orbital Hamiltonian group analysis. The reaction free energy changes calculations reveal that the oxygen evolution reaction should follow the pathway of H₂O → *OH → *O → *OOH → *O₂ with an overpotential of 0.81 V. Through an in-depth theoretical computational analysis in the atomic and electronic structures, the origin of photocatalytic oxygen evolution activity for PDI is well illustrated, which would help the rational design and modification of polymeric photocatalysts for efficient oxygen evolution.

Key words: Photocatalytic oxygen evolution, Polymeric perylene diimide, Atomic structure, Electronic structure, Reaction pathway