The insight into the neglected reduction process accompanied by UV-based oxidation process may provide new ideas for the development of advanced oxidation and reduction technologies. In this study, aniline was comprehensively investigated as an unexpected indicator of hydrated electron (e_aq⁻) under UV irradiation. Monochloroacetic acid (MCAA) was selected as the probe of e_aq⁻ and the balance of chloride ions indicated the reduction of MCAA. Further, laser flash photolysis experiments demonstrated the generation of e_aq⁻ in the UV/aniline process and the half-life period of formed e_aq⁻ was demonstrated to be 0.13 μs. The photolysis of aniline along with the decay of the excited state of aniline was responsible for the e_aq⁻ generation. Besides, the hydrogen atom (H) generated from the photolysis can subsequently reacted with OH⁻ to generate e_aq⁻. The photolysis pathways of aniline were proposed by the results of GC-MS. Aniline was abstracted of H in solution to the formation of aniline radical (PhNH) or form aminophenol in three different isomers (orto-, meta- and para-aminophenol). Moreover, UV/aniline showed a higher reducing capacity of MCAA compared with other organic electron donors and sustained a highly reducing ability in a wide pH. And the calculation results of quantum efficiency (Φ) showed that excessive aniline was not conducive to the elevation of Φ. This study introduced a novel pathway of e_aq⁻ generation during the photolysis of aniline and provided a new perspective for e_aq⁻-based advanced reduction processes.

深入了解伴随紫外氧化过程被忽视的还原过程，可能为高级氧化还原技术的发展提供新的思路。在这项研究中，苯胺作为紫外线照射_下水合电子 (e _aq ^- )的意外指示剂进行了全面研究。选择一氯乙酸 (MCAA) 作为 e _aq ^-的探针，氯离子的平衡表明 MCAA 减少。此外，激光闪光光解实验证明了在 UV/苯胺过程中 e _aq ^-的产生和形成的 e _aq ^-的半衰期被证明为 0.13 μs。苯胺的光解以及苯胺激发态的衰变是产生e _aq ^{- 的原因}。此外，光解产生的氢原子（H ）随后可以与OH ^-反应生成e _aq ^-。GC-MS的结果提出了苯胺的光解途径。苯胺被溶液中的H抽提形成苯胺自由基（PhNH) 或以三种不同的异构体（邻氨基苯酚、间氨基苯酚和对氨基苯酚）形成氨基苯酚。此外，与其他有机电子供体相比，UV/苯胺显示出更高的 MCAA 还原能力，并在较宽的 pH 值下保持高度还原能力。量子效率(Φ)的计算结果表明，过量的苯胺不利于Φ的升高。该研究引入了苯胺光解过程中 e _aq ^-生成的新途径，并为基于e _aq ^-的高级还原过程提供了新的视角。