ABOUT EML
We have investigated the various materials such as synthesis and application of luminescent materials (phosphor plate and perovskite quantum dot), nano-materials, and graphene-based materials for energy saving (supercapacitor) and conversion (water splitting).
First of all, we are studying luminescence materials such as perovskite quantum dot (QD) and ceramic phosphor plate (CPP) with YAG: Ce which is one of the representative phosphor materials. Ceramic phosphor plate using YAG: Ce has excellent thermal and mechanical properties and the packaging process is very easy and simple.
Additionally, we focus on the perovskite QD among various luminescence materials. Perovskite QD is one of the prospective next generation luminescent materials due to their outstanding electrical and optical properties. Perovskite QD has good optical properties, such as tunable wavelength & color, narrow-band, and high luminescence efficiency.
RESEARCH INTERESTS
Luminescence Materials
- Phosphor, Persistent phosphor, Perovskite LED, Quantum dots, Lead-free emitting materials
Ceramic phosphor plate, Phosphor in glass
Energy Materials
- Nano materials, Metal Organic Framework, Oxygen Evolution Reaction, Oxygen Reduction Reaction
Hydrogen Evolution Reaction, Hydrogen Reduction Reaction
Nanomaterials
•We have synthesized graphene sheets through Hummers method, tailor and CVD.
•Graphene show excellent properties of high electrical conductivity, stability, large surface area, and etc.
•In EML, we have investigated graphene hybrid materials of Nitrogen sulfur co-doped holey graphene hydrogel, Fe3O4@rGO@GO for applications such as energy conversion (water splitting), energy storage (Li and Na batteries and supercapacitors), and water treatment.
MOF (Metal Organic Framework)
•We have synthesized MOF materials by simple hydrothermal method.
•This materials facilitate to make designed and controlled nanostructures such as nanowire, hollow, porous and 3D structure. In addition, these show properties such as high specific surface area, many reaction sites and narrow diffusion pathway.
•In EML, we have investigated transition metal compounds (oxide, nitride, and sulfide) throughout post-processing of MOF for applications such as energy conversion (water splitting) and energy storage (Li and Na batteries and supercapacitors).
Light Emitting Materials (Display & Lighting)
• With increased demand for high-quality displays, a variety of luminescent materials have been developed such as organic luminescent materials and metal chalcogenide quantum dots to enrich the color gamut.
•From a material point of view, the demand has been increasing to develop the novel luminescent materials showing narrow FWHM (full width at half maximum) of the emission spectrum, high PLQY(photoluminescence quantum yield) and ease to control the emission wavelength.
•In our laboratory, we study halide perovskite which has narrow FWHM (<20 nm), high PLQY and composition based wide colour tunability (400~800 nm).
•All-inorganic CsPbX3 (X=Cl, Br, I) halide perovskite, that we have been synthesized can be a new material in a wide range of applications such as in optoelectronic devices.
Ceramic Phosphor Plate (Laser Lighting)
•We have synthesized YAG:Ce ceramic phosphor plate (CPP) using nano phosphor for high power laser diode (LD) application for white light in automotive lighting.
•Ceramic phosphor plate (CPP) is combined with a laser diode because it is very different from high power blue laser diodes, which provide both optical and thermal stability compared with the mixture of organic resin with phosphor. And also, Nano-structure based YAG CPP exhibited an increase in luminous emittance, luminous flux and conversion efficiency compared to YAG:Ce CPP with bulk phosphor.
•Our results suggest that this material can potentially serve as remote phosphors in phosphor converted LDs for white light generation.
