| 초록 |
To apply the graphene as an anode in organic opto-electronics, inherent low work function (WF) of graphene is serious problem due to the large energy level difference between graphene anode and overlying organic layers. This energy difference seriously disturbs hole-injection from graphene anode to organic layers. Here, we studied improved hole-injection properties of graphene anode through ultraviolet ozone (UVO) treatment. By performing the UVO treatment on surface of multi-layered graphene anode, we confirmed that sp2 hybridized chemical bonds of surface graphene layer is changed to oxygen related sp3 hybridized bonds, thereby opening the band gap of surface graphene layer. Band gap formation of surface graphene layer from UVO treatment increases surface potential of graphene anode. We confirmed that hole-injection property of graphene anode is improved by fabricating hole-only device with graphene anode. This results indicate that UVO treated graphene is promising anode in organic opto-electronics. |
