Structural effects induced by 2.5 MeV proton beam on zeolite 4A: Positron annihilation and X-ray diffraction study

• Structural effects of zeolite 4A induced by the proton beam depend on the implanted doses.
• The amorphization dose for zeolite 4A is approximately 1010 Gy.
• The effects of radiation on zeolite could be different for cage structures.
• Positron annihilation can become a effective method for studying irradiated zeolites.

Structural changes induced by 2.5 MeV proton beam in zeolite 4A were studied at fluences of 1.1016, 8.1016 and 2.1017 ion/cm2. Positron lifetime (LT) measurements were performed in vacuum after a heat treatment to remove the water from samples. X-ray diffraction method (XRD) was also applied to determine the changes in the crystallinity of zeolite. Gradual transformation of the crystalline structure to amorphous one can be observed in dependence of the implanted doses. Combination of LT and XRD provides a consistent view on structural effects induced by H+ beam in zeolite 4A.