Hyunil Kim

Size controlled nanographene oxides (NGOs; <50 nm) were prepared by a two-step oxidation process and NGOs were self-assembled with TiO 2 nanoparticles to form the core/shell structure. Nanosized GO-coated TiO 2 nanoparticles (NGOTs) were then reduced by a photocatalytic process under UV irradiation to obtain graphene-coated TiO 2 . This is clearly different from the typical graphene/TiO 2 composite with the particles-on-a-sheet geometry and is the first study on the core/shell structure of its k

The composite of different semiconductor nanoparticles may facilitate the charge separation and transfer because the difference in the band edge positions creates the potential gradient at the composite interface. For this purpose, the CdS–TiO 2 –WO 3 ternary hybrid was successfully synthesized and characterized for the structural, optical, and morphological properties by X-ray diffraction, diffuse reflectance UV/visible absorption spectroscopy, high-resolution transmission electron micrography,

This study demonstrates, for the first time in literature, <italic>in situ</italic> photocatalytic synthesis of hydrogen peroxide (H₂O₂) through sensitized triplet–triplet annihilation (TTA) upconversion (UC) of low-energy, sub-bandgap photons.

Thin amorphous TaO_xN_y layer-coated <italic>N</italic>-doped TiO₂ nanotubes successfully serve as a water splitting photoanode.

A phosphate (P)- and Mo-modified BiVO₄ photoanode and AQ-modified carbon cathode achieve efficient and durable photoelectrochemical production of H₂O₂ through dual processes.

High Resolution Image Download MS PowerPoint Slide Proper co-catalysts (usually noble metals), combined with semiconductor materials, are commonly needed to maximize the efficiency of photocatalysis. Search for cost-effective and practical alternatives for noble-metal co-catalysts is under intense investigation. In this work, nanodiamond (ND), which is a carbon nanomaterial with a unique sp 3 (core)/sp 2 (shell) structure, was combined with WO 3 (as an alternative co-catalyst for Pt) and applied

We provide a review of the progress in materials and applications of TTA-UC: biological, environmental/energy, OLED, and other applications. Moreover, an excellent demonstration of TTA-UC based technologies are presented in each chapter.

This study demonstrates the first reported photocatalytic decomposition of an indoor air pollutant, acetaldehyde, using low-energy, sub-bandgap photons harnessed through sensitized triplet–triplet annihilation (TTA) upconversion (UC). To utilize low-intensity noncoherent indoor light and maximize photocatalytic activity, we designed a plasmon-enhanced sub-bandgap photocatalyst device consisting of two main components: (1) TTA-UC rubbery polymer films containing broad-band plasmonic particles (Ag

Although the liver is the most common site for pancreatic islet transplantation, it is not optimal. We compared kidney, liver, muscle, and omentum as transplantation sites with regard to operative feasibility, and the efficiency of implantation and glycemic control. Islets from C57BL/6 mice were transplanted into diabetic syngeneic recipients. The mean operative time and mortality were measured to assess feasibility. To assess implantation efficiency, the marginal mass required to cure diabetes