Chulmin Choi

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We report the fabrication of three-dimensional (3D) branched nanowire (NW) heterostructures, consisting of periodically ordered vertical Si NW trunks and ZnO NW branches, and their application for solar water splitting. The branched NW photoelectrodes show orders of magnitudes higher photocurrent compared to the bare Si NW electrodes. More interestingly,(More)
Keywords: Concentrating solar power Solar absorber Cobalt oxide Light trapping High temperature a b s t r a c t Concentrating solar power is becoming an increasingly important part of the renewable energy portfolio. However, further cost reduction is desired to make CSP competitive with traditional energy technologies. Higher operating temperature is(More)
We report here a successful fabrication of a 3-D photoelectrode configuration having hydrothermally formed TiO 2 nanotubes on parallel Ti fins. The Ti fin arrays were assembled by simple and facile spot welding of alternately tall and short Ti foil assembly, which provides significantly increased electrode surface area. A tangled forest of nanotubes of TiO(More)
Hollow-sphere-structured magnetic nanocapsules containing intentionally trapped iron oxide nanoparticles and anticancer drugs have been prepared to provide a powerful magnetic vector under moderate gradient magnetic fields. It is shown that these nanocapsules can penetrate into the interior of tumors and allow a controlled ON–OFF switchable release of the(More)
We have developed patterned media via ion implantation using Au nano mask approach for local control of coercivity of magnetically hard multilayer film. Au nano-islands produced through a di-block copolymer templated technique is used as the mask for ion implantation. The sputter deposited multilayer film having vertical magnetic anisotropy is coated with a(More)
This paper reports on the extremely superhydrophobic behavior of supercritical CO2 processed silicon nanowires (SiNWs) with a contact angle in excess of ~177 °. Vertically aligned silicon nanowires with 10 nm to 40 nm diameter and 1 mm to 3 mm in length were obtained by electroless etching (EE) technique. The as-fabricated SiNWs were superhydrophilic with(More)
Highly sensitive hydrogen detection at room temperature can be realized by employing solution-processed MoS2 nanosheet-Pd nanoparticle composite. A MoS2-Pd composite exhibits greater sensing performance than its graphene counterpart, indicating that solvent exfoliated MoS2 holds great promise for inexpensive and scalable fabrication of highly sensitive(More)