Electronic structure of defected polyethylene for Schottky emission

Polyethylene is one of the most used solid state insulators in electrical power industry. It particularly to electrically insulate high-voltage cables. Under stresses associated with AC supplies, this material undergoes ageing, which often treeing. thought that phenomenon starts from gaseous defects embedded insulator bulk, leading formation a cluster cavities. Treeing able dig matrix until complete breakdown insulating components. Cavities are generated by sequence partial discharges. Each discharge triggered an electron emission surface at interface gas. The Schottky effect believed be likely mechanism cause emission. Our DFT modelling has suggested highly unlikely occur if neutral. DOS analysis revealed also related chemical defects. latter must exhibit electronic states slightly under conduction band. Furthermore, these sites act as trap for negative charge excess. A polyethylene system excess electron, combined specific oxidative groups, proved consistent experimental data.