ARTICLE Laser Flash Photolysis Mechanism of Anthraquinone-2-Sodium Sulfonate in Pyridine Ionic Liquid/Water Mixed System?

Gung-li Zhu?,Ling-wei Zhng,Yn-cheng Liu,Zhi-feng Cui,Xin-sheng Xu,Guo-zhong Wu?.Institute of Atomic nd Moleculr Physics,Anhui Norml University,Wuhu 241000,Chin.Shnghi Institute of Applied Physics,Chinese Acdemy of Sciences,Shnghi 201800,Chin(Dted:Received on Septemer 19,2015;Accepted on Decemer 7,2015)

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ARTICLE Laser Flash Photolysis Mechanism of Anthraquinone-2-Sodium Sulfonate in Pyridine Ionic Liquid/Water Mixed System?

Guang-lai Zhua?,Liang-wei Zhanga,Yan-cheng Liub,Zhi-feng Cuia,Xin-sheng Xua,Guo-zhong Wub?a.Institute of Atomic and Molecular Physics,Anhui Normal University,Wuhu 241000,China
b.Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China
(Dated:Received on September 19,2015;Accepted on December 7,2015)

The photochemical reaction process of anthraquinone-2-sodium sulfonate(AQS)in the mixture of water(H2O)and N-butylpyridinium tetra fl uoroborate([BPy][BF4])was studied using the laser fl ash photolysis technique.Experimental results show that the excited triplet of AQS(3AQS?)could react rapidly with H2O and the transient absorption spectra greatly changed by increasing the volume fraction of the ionic liquid(VIL)in[BPy][BF4]/H2O mixtures.The absorbance at 510 nm increased gradually with increasing VILwhen 0＜VIL＜0.1. By contrast,the absorbance decreased gradually when VIL＞0.1.Otherwise,the absorbance of the band near 380 nm steadily increased.The apparent kinetic parameters of transient species B and3AQS?are obtained approximately.3AQS?abstracting hydrogen from[BPy]+was also explored.It was deduced that the 350?420 nm band was the superposition of the peaks of3AQS?and AQSH·.The two reactions of3AQS?with[BPy][BF4]and H2O are a pair of competitive reactions.We also concluded that the entire reaction processes slow down in the case of high[BPy][BF4]concentrations.

Key words:Laser fl ash photolysis,Anthraquinone-2-sodium sulfonate,Ionic liquids,Transient absorption,Hydrogen abstraction

?Part of the special issue for“the Chinese Chemical Society’s 14th National Chemical Dynamics Symposium”.

?Authors to whom correspondence should be addressed.E-mail: zhglai@mail.ahnu.edu.cn,wuguozhong@sinap.ac.cn,Tel./FAX: +86-553-3869748