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3981817 
Journal Article 
Hydrated electron (e(aq)(-)) generation from p-benzoquinone/UV: Combined experimental and theoretical study 
Gu, Jia; Yang, L; Ma, Jun; Jiang, Jin; Yang, J; Zhang, J; Chi, H; Song, Y; Sun, S; Tian, W 
2017 
Yes 
Applied Catalysis B: Environmental
ISSN: 0926-3373 
212 
150-158 
WOS:000401134200017 
A p-benzoquinone (p-BQ)/UV process to induce hydrated electron (e(aq)(-)) generation was predicted by quantum chemical calculations and validated by experiment in this work. Theoretically, the photolysis of p-BQ under UV irradiation at 253.7 nm could induce water to generate e(aq)(-) with a molar ratio of 1:2 via the direct triplet mechanism, in which 1,4-addition reaction of the first triplet state of p-BQ with water was the key step. Experimentally, monochloroacetic acid (MCAA) (the probe of e(aq)(-)) was used to detect e(aq)(-) generated in the p-BQIUV process. The generation efficiency showed a positive linear dependence on the p-BQ concentration, which illustrated the crucial role of p-BQ on the generation of e(aq)(-). During the photolysis, p-hydroquinone was the primary intermediate for the generation of e(aq)(-). Kinetically, the energy barriers of the e(aq)(-) generation from p-HOC6H4OH, p-HOC6H4O- and p--OO6H4O- were 100.8 kcal mol(-1), 46.5 kcal mol(-1) and 5.6 kcal mol(-1), respectively. Both the experimental and theoretical results show that the generation of e(aq)(-) was much more efficient from the anions than that from pHOC(6)H(4)OH. The findings in the present study may help to understand the mechanism of e(aq)(-) generation from natural organic matters (NOM), since quinone-like groups are usually contained in NOM. (C) 2017 Elsevier B.V. All rights reserved. 
p-Benzoquinone; UV irradiation; p-Hydroquinone; Hydrated electron; Quantum chemical calculations