Retraction Note: Journal of Electronic Materials (2022) 51:4802-4807 https://doi.org/10.1007/s11664-022-09695-4

The author has retracted this article due to significant concerns with the validity of the results produced in this study. The article declared the presence of a disordered graphite carbon layer and compounds containing graphene or fullerene structures existing on the inner surface of the EP electrical tree channel, which exhibit fluorescence effects due to the presence of a large π-conjugated system and the 3D morphological characteristics of the EP electrical trees were obtained using the laser-induced autofluorescence effects of these substances, as shown in Fig. 4. However, the EP samples (bisphenol A epoxy resin) used in this article also exhibit obvious fluorescence effects due to the presence of Benzene rings, which cause background fluorescence interference that cannot be eliminated. Also, the author's affiliation in this article is not correct. The study was carried out at The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University. Qianqiu Shao agrees to this retraction.