Fully transparent quantum dot light emitting diode
Post# of 22456
Li Yao a , Xin Fang a , Wei Gu b , Wenhao Zhai a, Yi Wan a , Xixi Xie a , Wanjin Xu a,Xiaodong Pi b , Guangzhao Ran a *, Guogang Qin a
a State Key Laboratory for Microscopic Physics, School of Physics, Peking University, Beijing 100871, China.
b State Key Laboratory of Silicon Materials and School of Materials Science and Engineering, Zhejiang University, Hangzhou China.
Abstract
A new method to employ graphene as top electrode was introduced, and based on that, fully transparent quantum dot light emitting diodes (T-QLEDs) were successfully fabricated through a lamination process. We adopted the widely used wet transfer method to transfer bilayer graphene (BG) on polydimethylsiloxane/polyethylene terephthalate (PDMS/PET) substrate. The sheet resistance of graphene reduced to ~540 Ω/□ through transferring BG for 3 times on the PDMS/PET. The T-QLED has an inverted device structure of glass/Indium tin oxide (ITO)/ZnO nanoparticles/(CdSSe/ZnS quantum dots (QDs))/ 1,1-bis[(di-4-tolylamino)phenyl] cyclohexane (TAPC)/MoO3/ graphene/PDMS/PET. The graphene anode on PDMS/PET substrate can be directly laminated on the MoO3/TAPC/(CdSSe/ZnS QDs)/ZnO nanoparticles/ITO/glass, which relied on the Van der Waals interaction between the graphene/PDMS and the MoO3 . The transmittance of the T-QLED is 79.4% at its main electroluminescence peak wavelength of 622 nm.
This is a first success using a bilayered graphene as an anode instead of ITO. Thin enough to be transparent, Could be used for flexible electronics too.
http://pubs.acs.org/doi/abs/10.1021/acsami.7b02026