Publications by authors named "Hoang Nhat Hieu"

3D-ordered porous CdS/AgI/ZnO nanostructures were designed to perform as high-performance photoelectrodes for photoelectrochemical (PEC) water-splitting applications. They rely on the advantages of an extremely large active surface area, high absorption capacity in the visible-light region, fast carrier separation and transportation caused by the intrinsic ladder-like band arrangement. These nanostructures were fabricated by employing a three-stage experiment in a sequence of hard mold-assisted electrochemical deposition, wet chemical method and deposition-precipitation.

View Article and Find Full Text PDF

Highly responsive methanol sensors working at low temperatures are developed using hierarchical ZnO nanorods decorated by Pt nanoparticles. The sensing materials are fabricated following a 3-step process: electrospinning of ZnO nanofibers, hydrothermal growth of hierarchical ZnO nanorods on the nanofibers and UV-assisted deposition of Pt nanoparticles. The morphology, structure and properties of the materials are examined by field-effect scanning electron microscopy, transmission electron microscope, x-ray diffraction, x-ray photoelectron spectroscopy, UV-Vis absorption spectroscopy, and electrical measurements.

View Article and Find Full Text PDF

Nanostructures of titanium nitride (TiN) have recently been considered as a new class of plasmonic materials that have been utilized in many solar energy applications. This work presents the synthesis of a novel nanostructure of TiN that has a nanodonut shape from natural ilmenite ore using a low-cost and bulk method. The TiN nanodonuts exhibit strong and spectrally broad localized surface plasmon resonance absorption in the visible region centered at 560 nm, which is well suited for thermoplasmonic applications as a nanoscale heat source.

View Article and Find Full Text PDF

The electrodes in photoelectrochemical cells responsible for the generation of hydrogen and oxygen by water splitting have been intensively studied because of their high photon-to-electron conversion efficiency. The morphology of nanostructures with these high-efficiency electrodes was systematically compared with the morphology of ZnO structures with vertically aligned nanorod arrays (NA), hollow hemisphere arrays (HA), urchin-like (UL) nanorod arrays, and thin films (TF). The UV-vis light absorption, photoresponse (current-voltage characteristics in the dark and under light), and photoelectrochemistry of the electrodes were measured.

View Article and Find Full Text PDF