Effect of silver nanoparticles deposited on indium tin oxide by plasma-assisted hot-filament evaporation on phosphorescent organic light-emitting diode performance
Document Type
Article
Publication Date
12-30-2021
Abstract
This study investigates a high-density of silver (Ag) nanoparticles deposition in a two-dimensional array via a plasma-assisted hot-filament evaporation system on indium tin oxide (ITO) anodes for phosphorescent organic light-emitting diodes (PhOLEDs). The nanoparticles deposition process was conducted at substrate temperatures of 25, 80 and 140 degrees C. It is observed through atomic force microscopy that the deposited Ag nanoparticles size increases with higher substrate temperature. The surface plasmon resonances (SPRs) of the deposited Ag nanoparticles are influenced by particle size and interparticle spacing. The visible light transmittance of PhOLED was improved in the wavelength range from 500 to 600 nm at 25 and 80 degrees C conditions. The luminance efficiency of PhOLEDs with deposited Ag nanoparticles increased by 11.07, 5.03, and 70.30% with rising temperature compared to the standard PhOLED (no Ag nanoparticle) with colour stability. The enhancement in efficiency resulted from a coupling between the SPR of Ag nanoparticles and excitons in the emitting layer. The maximum efficiency was also due to a mirror-reflected emission effect via the larger Ag nanoparticles size. Moreover, the positive charges from the inner layer of the anode were enhanced by the high-density inserted Ag nanoparticles at 25 and 80 degrees C, increasing the hole carrier injection. The performance and mechanism of a PhOLED modified with Ag nanoparticles are discussed.
Keywords
Phosphorescent organic light-emitting diode, Silver Nanoparticles, Plasma-assisted hot-filament evaporation, Luminance, Hole injection
Divisions
Science
Funders
University of Malaya Research Grant (FRGS FP113-2019A)
Publication Title
Applied Surface Science
Volume
570
Publisher
Elsevier
Publisher Location
RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS