Polyaniline/Perylene diimide organic heterojunction photocatalyst with three-dimensional structure (3D PANI/PDI) has been successfully prepared via an in-situ growth process. 3D PANI/PDI exhibited efficient performance in the degradation of tetracycline (TC) under visible light irradiation. The degradation rate of TC by 3D 20%-PANI/PDI is 15.3 times and 17.0 times that of pure PDI and PANI in static system, respectively. Moreover, 3D PDI/PANI showed outstanding stability and could continuously degrade TC for up to 75 h in a dynamic system. The enhanced photocatalytic performance and stability of 3D PANI/PDI mainly comes from the following three aspects: (i) The introduction of PANI polymer backbone reinforced the strength of the PDI hydrogel, thereby improved the catalytic stability of the system; (ii) The three-dimensional network structure provided more reactive sites and medium transport channels; (iii) Larger delocalized π-electron conjugated system and energy-matched heterojunction structure were established through π-π interactions between PANI and PDI, which improved the efficiency of the migration and separation of photo-generated carriers. Finally, the mechanism and mineralization pathways of TC were systematically studied. Superoxide radical (O₂⁻), hydrogen peroxide (H₂O₂) and hole (h⁺) were the main reactive species (RSs) for the degradation of TC. Under the attack of RSs, the TC under hydroxylation, dealkylation, aromatization, and ring-opening processes, eventually leading to complete mineralization. This work provides a new promising approach for improving the photocatalytic performance of organic catalysts and indicates that 3D PANI/PDI organic heterojunction photocatalyst can be efficiently applied for the water environmental remediation.

通过原位生长过程成功地制备了具有三维结构的聚苯胺/ Per二酰亚胺有机异质结光催化剂（3D PANI / PDI）。3D PANI / PDI在可见光照射下对四环素（TC）的降解表现出有效的性能。在静态系统中，3D 20％-PANI / PDI对TC的降解率分别是纯PDI和PANI的15.3倍和17.0倍。此外，在动态系统中，3D PDI / PANI表现出出色的稳定性，并且可以连续降解TC长达75小时。3D PANI / PDI增强的光催化性能和稳定性主要来自以下三个方面：（i）PANI聚合物骨架的引入增强了PDI水凝胶的强度，从而提高了系统的催化稳定性；ii三维网络结构提供了更多的反应场所和中等运输渠道；（iii）通过PANI和PDI之间的π-π相互作用建立了更大的离域π电子共轭体系和能量匹配的异质结结构，从而提高了光生载流子的迁移和分离效率。最后，系统地研究了TC的机理和成矿途径。超氧自由基（Ò ₂ ^- ），过氧化氢（H ₂ ö ₂）和孔（H ⁺）为为TC的降解主要反应性物质（RSS）。在RS的攻击下，TC处于羟基化，脱烷基化，芳构化和开环过程中，最终导致完全矿化。这项工作为改善有机催化剂的光催化性能提供了一种有希望的新方法，并表明3D PANI / PDI有机异质结光催化剂可以有效地应用于水环境修复。