冰晶中双氧水的UV光解

PHOTOLYSIS OF HYDROGEN PEROXIDE IN ICE

本文采用253.7 nm的紫外灯光解冰晶中的双氧水,研究其光解率随光照时间和温度的变化.以及Cl^-,SO_4^(2-)和CO_3^(2-)对其降解的影响,结果表明,相同条件下三种离子对其影响大小依次为:Cl^->SO_4^(2-)>CO_3^(2-).对比冰晶和水溶液中双氧水的光解,冰晶中双氧水的光解速率低于水溶液中双氧水的光解速率.紫外-可见光谱(UV-vis)分析其光解产物,没有发现新的物质生成.由此可以认为,冰晶中双氧水主要在冰晶笼子中进行反应,少部分在类似液体层(QLL)中降解.

The photolysis of hydrogen peroxide （ H2O2 ） in ice was investigated with 253.7 nm UV light. We have studied the relationship between photolysis efficiency of H2O2 with irradiation time as well as temperature. The effect of three types of inorganic ions （ Cl^-, SO4^2- and CO3^2- ） on H2O2 photolysis rate in ice has also been reported, which followed the order： Cl^- 〉 SO4^2- 〉 CO3^2-. H2O2 photolysis in ice appeared to be slower than that in aqueous solution at the same condition. No new photolysis products were observed using UV-Vis spectra analysis. On the basis of our experiment, we inferred that most of H2O2 photolysis took place in ice cage, while only small parts occurred in quasi-liquid layer （QLL）.