Transparent shape memory polyimide enables OLED for smart deformation

An innovative process for producing flexible transparent graphene electrodes has been proposed. The electrochemically polished copper-foil was used as the metal substrate to prepare high-quality monolayer graphene. Monolayer graphene was transferred from copper-foil to transparent shape memory polyimide (TSMPI) intactly by novel flow-casting transfer technology, and the smart, ultra-clean and smooth flexible graphene electrode (pG@TSMPI) was fabricated. The light transmittance of pG@TSMPI at 550 nm is 86%, the average sheet resistance is 310 Ω/sq, and the surface roughness (Ra) is 18 nm. Smart white OLED was manufactured using pG@TSMPI as transparent anode, and its luminescence performance was comparable to that of ITO-based device. Depending on the shape memory effect of TSMPI substrate, the smart OLED has the superiorities of variable stiffness and reconfigurable shape, which can transform from 2D structure into complex 3D structure.