Performance enhancement of amorphous WO3 assisted graphene-based electronic devices: Aspect of surface engineering

Highlights: • Amorphous WO₃ intermediate layer was used to protect the graphene surface. • The WO₃ was dissolved in a deionized water, and no damage occurred to graphene surface. • The performance enhancement was quantitatively verified via the photodetector. • The surface-protected photodetector recorded a 1.74 times higher photoresponsivity and 4s faster temporal photo response time. After the successful synthesis of graphene using chemical vapor deposition in 2009, the large-area/defect-free transfer method still remains a critical issue for implementing high-performance graphene-based electronic devices. Here, for the first time, we demonstrated a specially prepared water-soluble amorphous WO₃ intermediate layer to effectively protect the graphene surface from immediately after its synthesis to transfer and final unit processing. Moreover, using the photodetector to which the proposed protection method was applied, the performance improvement was quantitatively verified. Compared with the control device, the surface-protected photodetector recorded a higher photoresponsivity of 1.74 times and faster temporal photoswitching response time of 4 s or more. The graphene surface protection method using the WO₃ intermediate layer allows the reversibility in transfer process and performance enhancement of graphene-based electronic devices.