; Li Yu-Xiao] Zhengzhou Univ, Coll Phys Engn, Zhengzhou 450001, Peoples R China
; [Yu Run-Sheng
; Qin Xiu-Bo
; Wang Bao-Yi
; Jia Quan-jie] Chinese Acad Sci, Inst High Energy Phys, Key Lab Nucl Anal Tech, Beijing 100049, Peoples R China
Mesoporous silica thin films with different pore shapes were prepared by evaporation induced self-assembly method. The synchrotron radiation x-ray reflectivity and slow positron annihilation techniques were used to characterize the pore structures. The results indicated that with increase of the spin-coating speed, the pore structure transformed from 3-D cubic to 2-D hexagonal, the average porosity also decreased. The correlation of the film structures and positron annihilation parameters was songht for with FT-IR spectroscopy and isotropic inorganic pore contraction model.