Complex films of mercapacetic acetic (MPA) and ZnO were formed by adding ZnO nanocrystals film on Si substrate to the chloroform solution of mercaptoacetic acetic.The Zn-S bond was formed

which may be demonstrated by XPS.The fluorescence properties of ZnO thin film has been influenced by the amount of coated mercaptoacetic acids.With increasing the amount of mercaptoacetic acids

the ratio of coated surface increased.By characterization of photoluminescence

we found that the free exciton and bound exciton decreased.To those phenomena

we explained them by the electron transfer between ZnO and mercaptoacetic.Firstly

when bonds between ZnO and mercaptoacetic were formed

the electrons excited wouldn't combine with holes and the electrons would transfer into the level of mercaptoacetic acids.Thus

the ratio between electrons and holes of ZnO decreased and the intensity of its photoluminescence decreased.Secondly

the amount of mercaptoacetic acids would influence on the ratio of electrons and holes of ZnO.The mercaptoacetic acids increased

the ratio of electron transfer enhanced.So we may obtain the data of photoluminescence that the intensity of photoluminescence decreased with increasing the amount of mercaptoacetic acids.Otherwise

the profile photoluminescence of ZnO modified with mercaptoacetic acids showed that the intensity of ZnO photoluminescence decreased gradually with the distance of ZnO layer near to the surface.