10.2.1.3　Conductive materials

Conductive materials are the key materials in e-skin.At present，people have applied a variety of conductive materials to e-skin.As the carbon materials，such as carbon nanotubes and graphene have excellent electrical and mechanical properties and high chemical stability，they are widely used in the preparation of e-skin.In recent years，semiconductor nanowires（e.g.，silicon，gallium arsenide，and cadmium selenide nanowires）and metal nanowires（e.g.，gold，silver，and copper nanowires）have also been used in the preparation of e-skin.However，because the preparation methods of nanowires are usually more complicated and costly，their applications are subject to certain restrictions.In recent years，organic polymer conductor materials have been applied to the preparation of e-skin.Common materials include poly-3-hexylthiophene，polyaniline，polypyrrole，poly（3，4-ethylenedioxythiophene）/polystyrene sulfonic acid（PEDOT：PSS），etc.Organic semiconductor materials generally have good processing properties，and their mechanical properties are closer to those of human skin.Therefore，compared with materials such as carbon nanotubes，graphene，and metal nanowires，organic semiconductor materials are more suitable for preparing large-area flexible e-skin devices.(https://www.daowen.com)