121st General Meeting of the KCS

Type Poster Presentation
Area Physical Chemistry
Room No. Event Hall
Time 4월 20일 (금요일) 11:00~12:30
Code PHYS.P-239
Subject Improvement of luminous efficiency of NaYF4: Yb, Er upconversion films using silver deposition
Authors Lim SooYeong, Youngho Cho1, Chan Ryang Park1,*, Hyung Min Kim*
Department of Bionano Chemistry, Kookmin University, Korea
1Department of Chemistry, Kookmin University, Korea
Abstract Some rare earth metals have a feature that has an optical phenomenon called upconversion (Upconversion; UC). This phenomenon occurs when two or more photons are absorbed in the excited state and emit light at a higher energy than the incident light. Typical upconversion materials comprise NaYF4 as a host and include rare earth metals such as Yb and Er. Using these characteristics, it has been used in solar cells, displays and the development of lasers laser. Recently, it has been used for biomedical image research using UCNP (upconversion nano particles; UCNP). In addition, when a transparent film having a pattern is formed using an UC material, the information is recognized only when the light in the infrared region is irradiated. Therefore, it is expected to be used in the field of security, information and anti-counterfeiting. By using PLD method (pulsed laser deposition; PLD), it was made easier than existing upconversion film making method and succeeded in manufacturing transparent film by adjusting refractive index of film. However, due to the low quantum efficiency of the UC material itself, a high power light source was required to obtain the information of the film. To overcome this problem, when the substrate of the film is not damaged at high temperature, the film is annealed by exposing it to high temperature to improve the crystallinity of the UCF (upconversion film; UCF) and improve the efficiency by removing the defect site. On the other hand, when the film is like a thin plate, there is a problem in that the film is damaged and information is deformed by using the above method. In this case, when a metal layer is formed during film production, the luminous efficiency of the film is increased due to the surface plasmon resonance effect. Silver was used as the metal, and the experiment was classified into three kinds according to the position of the SL (silver layer; SL). First, the SL under the UCF was formed, then the SL was formed on the UCF, and finally the silver and UC materials were simultaneously deposited.
E-mail smart1412@kookmin.ac.kr