Inkjet Printed Imbedded Graphene Nanoplatelet/Zinc Oxide Bulk Heterojunctions Nanocomposite Films for Ultraviolet Photodetection
Abstract
A ZnO solgel precursor (ZnOPr) and graphene nanoplatelets (GnPs) are mixed into a composite ink for inkjet printing photodetectors with bulk heterojunctions of ZnO/GnP on a heated SiO2/Si substrate. Heating of the SiO2/Si wafers at 50 deg C was found optimal to prevent segregated droplets on the hydrophobic surface of the SiO2/Si substrate during printing. After printing the ZnO/GnP channels, thermal annealing at 350 deg C for 2 h was performed for crystallization of ZnO and formation of the ZnO/GnP heterojunctions. The GnP concentration was varied from 0, 5, 20, and 30 mM to evaluate optimal formation of the ZnO/GnP bulk heterojunction nanocomposites based on ultraviolet photoresponse performance. The best performance was observed at the 20 mM GnP concentration with the photoresponsivity reaching 2.2 A/W at an incident ultraviolet power of 2.2 micro W and a 5 V bias. This photoresponsivity is an order of magnitude better than the previously reported counterparts, including 0.13 mA/W for dropcasted ZnO-graphite composites and much higher than 0.5 A/W for aerosol printed ZnO. The improved performance is attributed to the ZnO/GnP bulk heterojunctions with improved interfaces that enable efficient exciton dissociation and the charge transport. The developed inkjet printing of solgel composite inks approach can be scalable and low cost for practical applications.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 18, 2019
- Accession Number
- AD1103078
Entities
People
- Alex Corbin
- Ashley Tramble
- Brent Cook
- Dan Ewing
- Judy Z. Wu
- Maogang Gong
Organizations
- University of Kansas