Searcharxiv⌕ Search

arXiv subjects

Sándor Lenk

Publications and source records attributed to Sándor Lenk.

2 recordsLinked to original sources

Thiolation and PEGylation of silicon carbide nanoparticle

In this study, we implement thiol termination on the surface of few-nanometer-sized silicon carbide (SiC) nanoparticles (NPs) to enable further applications, such as fluorescent biomarkers. Various spectroscopic techniques are employed to monitor the effectiveness of the surface treatment. A thiol-Michael addition reaction is performed by conjugating 4-arm PEGmaleimide molecules to the thiol groups of SiC NPs, further demonstrating the reactivity of thiol-terminated SiC NPs, which also acts as a protection layer against oxidation. These fluorescent thiolated SiC NPs, both with and without conjugated molecules, are directly applicable as bioinert probes. Since SiC NPs can potentially host room-temperature fluorescent defect quantum bits, our results are an important step to realize a bioinert, ultrasmall quantum sensor bioagents, which may open new avenues in biotechnology.

cond-mat.mtrl-sci↗

Near-field optical investigation of Ni clusters inside single-walled carbon nanotubes on the nanometer scale

We used scattering-type scanning near-field optical microscopy (s-SNOM) to characterize nickel nanoclusters grown inside single-walled carbon nanotubes (SWCNT). The nanotubes were filled with Ni(II) acetylacetonate and the molecules were transformed into nickel clusters via annealing. The metal clusters give high local contrast enhancement in near-field phase maps caused by the excitation of free charge carriers. The near-field contrast was simulated using the finite dipole model, approximating the clusters with elliptical nanoparticles. Compared to magnetic force microscopy, s-SNOM appears much more sensitive to localize metal clusters inside carbon nanotubes. We estimate the detection threshold to be ~600 Ni atoms.

cond-mat.mes-hall↗