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)



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