A research team led by Dr. Byeong-dae Choi at Korea’s Daegu Gyeongbuk Institute of Science and Technology (DGIST) has made significant advancements in improving the efficiency of zinc sulfide powder-based electroluminescent (EL) devices by incorporating silver nanofilms. The study, published in the June 2023 edition of Advanced Photonics Research, highlights the potential for these innovations in the display industry.
Powder-based EL devices offer great potential for flexible curved lighting and displays. However, their low efficiency has hindered practical applications. Researchers have now addressed this challenge by incorporating a silver nanothin-film into the EL devices, resulting in significant efficiency improvements.
The study focused on analyzing the characteristics of EL devices, particularly the properties of an indium-tin-oxide (ITO) electrode. It was found that as the emission area of the EL device decreased, the power loss per unit area increased, leading to decreased device efficiency.
To combat this power loss, the research team developed a solution using a silver nanothin-film. A several-nanometer-thick silver film was applied to a polyethylene terephthalate film, achieving high transmittance of 88% and a low sheet resistance of 10 Ω/sq. The team then printed an EL paste on top of this film and stacked an upper electrode to create an EL device with a sandwich structure.
The results were remarkable. Compared to a device with an ITO film-based electrode featuring a sheet resistance of 40 Ω/sq, the EL film device with the silver nanothin-film electrode exhibited lower power consumption and approximately 12% higher device efficiency. These efficiency gains represent a significant step forward in the development of practical EL devices.
The findings of this study not only provide insights into the efficiency-enhancing properties of silver nanothin-films but also pave the way for future research on stretchable and bendable EL displays. By leveraging the advantages of powder-based EL technology and the efficiency improvements achieved with silver nanothin-films, the development of more efficient and versatile EL devices is within reach.
Research
Yun, S., Lee, S., Allabergenov, B., Park, J.C., Moon, S., Lee, S.E. and Choi, B. (2023), Efficiency Improvement in a Powder-Based Flexible Electroluminescence Device using Ag Nanothin-Film-Coated Transparent Electrodes. Adv. Photonics Res., 4: 2200291. https://doi.org/10.1002/adpr.202200291
