▎ 摘　　要

The effect of UV irradiation on the wettability of GO films, as well as the possibility of making a film with different properties of its surface, the Janus film, has been studied. The O/C ratio changes from 0.32 to 0.26 after 6 h of UV irradiation. The contact angle of water droplet wetting on an unirradiated surface is theta approximate to 35 degrees. The contact angle reaches more than 95 degrees on the irradiated surface, which means that a hydrophobic surface on a film can be obtained. The origin of amphiphilic properties of the GO film are associated with the photochemical reduction of GO.