硫化镉胶粒界面自由基反应动力学的ESR研究

用电子自旋共振波谱方法研究了半导体超微粒子表面光诱导电子转移所引发的底物的次级自由基反应动力学过程.结果表明,用含有水溶性草酸盐的硫化镉(CdS)胶体体系产生的COO·^-离子基,可以较方便地引发其它自由基反应,并根据已知的由DMPO捕捉COO·^-的反应速度常数数据,去计算COO·^-基与其它可产生稳定自由基的化合物进行反应的速度常数值,从而在此基础上发展了一种研究自由基反应动力学的行之有效的简便的新途径和新方法,可以较广泛地应用于其它凝聚相的自由基反应动力学体系的研究.

ESR STUDY ON THE PHOTOREACTION KINETICS OF FREE RADICALS ON THE SURFACE OF CdS SUPERFINE PARTICLES

The secondary reaction kinetics processes of free radicals initiated by photoinduced electron transfer occured on the surface of semiconductor superfine particles were studied by means of ESR method. The results indicated that a lot of free radical reactions can be conveniently initiated with the help of COO -. ion radical produced in the colloid system of Cadmium Sulfide(CdS) containing water soluble oxalate, and the rate constants of reactions of ion radical COO + -. with other compounds may be calculated out according to the known rate constants of the addition reaction between spin trap DMPO and ion radical COO -. , so as to develop a simple and effective approach for studying the kinetics of free radical reactions. Obviously, this method shall be extensively used in the research of other kinetics systems of free radical reactions taken place in condensed phase.