arXiv subjects

Hung-Kai Yu

Publications and source records attributed to Hung-Kai Yu.

3 recordsLinked to original sources

arXiv2025

Surface Hydrogen Coverage on Pt/Graphene Measured by Carbon Ion ERDA

Graphene, a two-dimensional monolayer of sp2-bonded carbon atoms in a honeycomb lattice, possesses exceptional electronic, mechanical, and quantum properties, making it highly attractive for energy storage, spintronics, and microelectronics. Functionalizing graphene with platinum (Pt) adatoms can further enhance its properties, particularly for hydrogen storage applications. In this study, we experimentally investigate hydrogen adsorption on Pt-decorated graphene using Elastic Recoil Detection Analysis (ERDA). By irradiating the Pt/graphene film with a 4.1 MeV C2+ ion beam and detecting recoiled hydrogen atoms at a 30 degree scattering angle, we obtain the hydrogen depth profile, providing critical insights into its storage behavior.

cond-mat.mtrl-sci↗

arXiv2019

Process Verification of Magnetic Ion Embedded Nanodiamonds Using Secondary Ion Mass Spectroscopy

Ion implantation is used to create magnetic ion embedded nanodiamonds for use in a wide range of biological and medical applications; however, the effectiveness of this process depends heavily on separating magnetic nanodiamonds from non-magnetic ones. In this study, we use secondary ion mass spectrometry to assess the distribution of magnetic ions and verify the success of separation. When applied to a series of iron/manganese embedded nanodiamonds, the sorting tool used in this study proved highly effective in selecting magnetic nanodiamonds. This paper also discusses the major challenges involved in the further development of this technology.

physics.app-ph↗

arXiv2019

Iron Embedded Magnetic Nanodiamonds for in vivo MRI Contrast Enhancement

Although nanodiamonds have long being considered as a potential tool for biomedical research, the practical in vivo application of nanodiamonds remains relatively unexplored. In this paper, we present the first application of in vivo MRI contrast enhancement using only iron embedded magnetic nanodiamonds. MR image enhancement was clearly demonstrated in the rendering of T2-weighted images of mice obtained using an unmodified commercial MRI scanner. The excellent contrast obtained using these nanodiamonds opens the door to the non-invasive in vivo tracking of NDs and image enhancement. In the future, one can apply these magnetic nanodiamonds together with surface modifications to facilitate drug delivery, targeted therapy, localized thermal treatment, and diagnostic imaging.

physics.med-ph↗