Publications by authors named "Song Yeul Lee"

There is a growing demand for research and development of advanced energy storage devices with high energy density utilizing earth-abundant metal anodes such as sodium metal. Tellurium, a member of the chalcogen group, stands out as a promising cathode material due to its remarkable volumetric capacity, comparable to sulfur, and significantly high electrical conductivity. However, critical issues arise from soluble sodium polytellurides, leading to the shuttle effect.

View Article and Find Full Text PDF

Sodium-ion capacitors (SICs) bridge the performance gaps between batteries and supercapacitors by providing a high energy and power density in a single configuration. As battery-type active materials, sodium preintercalated layered metal oxides are desirable owing to their unique crystal structure, simple synthesis process, and high working voltage. However, their poor cyclic stability and low kinetics limit their application.

View Article and Find Full Text PDF
Article Synopsis
  • - Raman spectroscopy is a powerful imaging technique that uses unique spectral signatures for high specificity, but traditional metallic gold nanoparticles over 10 nm pose challenges in excretion for clinical applications.
  • - The study introduces biodegradable Raman-active gold supraclusters that can be broken down into excretable nanoclusters, maintaining effective Raman signal strength despite their smaller size.
  • - These supraclusters show promising results in imaging acidic tumors in mice, with 73% of the administered dose excreted within four months, highlighting their potential for safe clinical use in Raman imaging.
View Article and Find Full Text PDF

Elucidation of upconversion nanoparticles (UCNPs) that can be excited by near-infrared (NIR) light is an interesting topic in the field of photodynamic therapy (PDT). However, the PDT efficiency of conventional UCNPs is limited due to the low quantum yield and overheating effect of the 980 nm light source. In this study, a light source with a wavelength of 808 nm was used as an excitation source for Nd-doped UCNPs to solve the overheating effect.

View Article and Find Full Text PDF

Lanthanide-doped nanoparticles exhibit unique optical properties, such as a long luminescence lifetime (up to several milliseconds), sharp emission peaks, and upconversion luminescence over the range of wavelengths from near-infrared to visible. Exploiting these optical properties, lanthanide-doped nanoparticles have been widely utilized for cellular and small animal imaging with the absence of background autofluorescence. In addition, these nanoparticles have advantages of high signal-to-noise ratio for highly sensitive and selective diagnostic detection.

View Article and Find Full Text PDF