1. Inkjet‐Printed p‐NiO/n‐ZnO Heterojunction Diodes for Photodetection Applications
- Author
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Sergio González, Giovanni Vescio, Juan Luis Frieiro, Alina Hauser, Flavio Linardi, Julian López‐Vidrier, Marek Oszajca, Sergi Hernández, Albert Cirera, and Blas Garrido
- Subjects
Mechanics of Materials ,Mechanical Engineering ,Oxides ,Optoelectronics ,Òxids ,Optoelectrònica ,Light emitting diodes ,Díodes electroluminescents - Abstract
Transparent Conducting Oxides (TCOs) are an enticing family of optoelectronic materials which have been proven to increase efficiency when incorporated into perovskite light emitting diode (PE-LED) and organic OLED architectures as transport layers. Solution-processed metal oxide inks have already been demonstrated, although there is still a need for high-quality inkjet-printable metal oxide inks with a thermal post-process below 200 °C. The set of inks in this work are adapted from low-boiling point colloidal suspensions of metal oxide nanoparticles synthesized via flame spray pyrolysis. High quality, pinhole- and wrinkle-free inkjet-printed layers are obtained at low temperatures through vacuum oven post process, as proven by scanning electron microscopy. The crystallinity of the layers is confirmed by X-ray diffraction, showing the expected hexagonal and cubic structures respectively for ZnO and NiO. The thin film layers reach over 70% (ZnO) and 90% (NiO) transparency in the visible spectrum. Their implementation in the inkjet-printed p-n diode shows excellent I-V rectifying behavior with an ON/OFF ratio of two orders of magnitude at ±3 V and a forward threshold voltage of 2 V. Furthermore, the device exhibits an increase in photocurrent around four orders of magnitude when illuminated under a 1-sun solar simulator.
- Published
- 2023