RESEARCH INTERESTS

  • NANOPHOTONICS
    QDs can modulate the wavelength and intensity of emitted light, so they have possible application as switch probes for cellular and whole-body imaging, as optical modulators, and as light-emitting diodes. We synthesize various types of NPs, including core/shell QDs, nanorods, nanotetrapods and nanoporous materials. We have achieved photomodulation of QD conjugate by additional UV excitations that induce the electron transfers to QDs and quench their photoluminescence. We have also used inorganic capping-ligand QDs to sensitize solar cells.
  • NANOCLUSTERS
    Magic-sized clusters (MSCs) can be isolated as intermediates in quantum dot (QD) synthesis, and they provide pivotal clues in understanding QD growth mechanisms. Mechanistic studies on QDs often identify magic-sized clusters (MSCs) as intermediates between molecular precursors and final QDs MSCs are distinguished from a small size of nanoparticles (NPs), because MSCs are thermodynamically more stable than expected ones in similar size NPs. A colloidal semiconductor MSC usually consists typically less than hundreds of atoms with characteristic absorption features at fixed wavelengths.
  • NANOBIOTECHNOLOGY
    QDs present a possible new technology for in vivo bio-imaging and future medical imaging applications. QDs have proven potential as imaging contrast agents due to their bright luminescence, their resistance to photobleaching, and their tunable emission wavelengths. We developed NIR-II-emitting QD probes, and have achieved cancer diagnosis by using QD-Antibody conjugates. Also, we showed QDs in an amphiphilic polyethyleneimine derivative platform for cell labeling, targeting, gene delivery, and ratiometric oxygen sensing.
  • NANOPLASMONICS
    Metals can display Surface Plasmon Resonance (SPR) when their sizes are reduced to the nanoscale. The applications of noble metal NPs can be very diverse such as spectroscopic and imaging tools, because SPR properties can be tailored by choosing metals with appropriate dielectric properties, and by selecting the size, shape, local environment of nanoscale metallic structures. We proposed novel metal NP complexes that could be used for highly-efficient cancer therapy and for photoacoustic-guided drug delivery.

PUBLICATIONS

ACS Nano 2025 19, 48, 41213
"Discrete Cation Exchange in AgAuS Quantum Dots Using Reactivity Engineered Cation Precursors“
Jisu Kwon, Wonseok Lee, Yoonbin Shin, Jaelim Kim, Yunmo Sung, Eunsung Lee* and Sungjee Kim*
ACS Nano 2025 19, 34, 30810
"Quantum Dot Composite Colloids with Layer-by-Layer Shells: Biological Self-Assemblies for Signal Amplified Detection“
Wonseok Lee, Junhwa Lee, Hyunjung Lee, Mirae Han, Young Ho Ko, Chan-Gi Pack, Joonhyuck Park* and Sungjee Kim*
Nano Letters 2025 25, 29, 11391
"Implementing Discrete Multistate Electrochemical Response to Colloidal Quantum Dots via Regulated Charge Transfer Pathways“
Yunmo Sung, Taeyong Ha, Sukyung Choi, Ho Jin* and Sungjee Kim*
Accounts of Materials Research 2024 5, 9, 1097
"Silver Sulfide Nanocrystals and Their Photodetector Applications“
Jisu Kwon, Yoonbin Shin, Yunmo Sung, Hyunmi Doh, and Sungjee Kim*
J. Phys. Chem. C 2024 128, 4, 1809
"Multiple Roles of Magic-Sized Clusters in Quantum Dot Synthesis“
Eunjae Lee, Yongju Kwon, Anastasia Agnes, Youngjae Ryu, and Sungjee Kim*