In this paper, the charge storage performance of electrospun poly(ethylene terephthalate) (PET) mats with high specific surface area was evaluated in comparison to that of PET film electrets. Corona discharge method was used to charge the electrospun PET mats and PET films. The surface potential decay measurements revealed that the corona charged PET mats had higher initial values for the normalized surface potential compared to the PET electret films. A tendency for stabilization of the electret charge to one and the same value for all charged samples (mats and films) after the 50th day was observed. The peaks at 90 degrees C in the thermally stimulated current (TSC) spectra of uncharged and charged in corona discharge electrospun PET mats were observed and attributed to a relaxation of the separated space charges, the dipole disorientation or injected charges within the bulk. It was found that the value of the storage charge in a corona charged electrospun PEr mats was higher than that in PET mats prepared by electrospinning. (C) 2008 Elsevier Ltd. All rights reserved.