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One-dimensional hybrid nanostructures composed of a plasmonic gold nanowire core covered by a shell of magnetic oxide nanoparticles (Au@Fe x O y NWs) were synthesized by a one-pot solvothermal synthesis process. The effects of reaction temperature, time, reducing agent, and precursor as well as postsynthesis treatment were optimized to produce highly uniform NWs with a diameter of 226 ± 25 nm and a plasmonic core aspect ratio of 25 to 82. By exploiting the interaction of NWs with an external magnetic field, precise arrangements into highly periodic photonic structures were achieved, which can generate distinctive structural colors that are vividly iridescent and polarization-sensitive. Furthermore, a Bouligand-type chiral nematic film consisting of multistacked unidirectional layers of achiral NWs was fabricated using a modified layer-by-layer deposition method, which displays circular dichroism (CD) and chiral sensing capability. The addition of bovine serum albumin (BSA) as a model protein analyte induced a concentration-dependent wavelength shift of CD peaks. These intriguing properties of magnetoplasmonic anisotropic NWs and their self-assemblies could be consequently valuable for developing nature-inspired structural color imprints as well as solid-state chiral sensing devices.

The successful realization of high-performance 2D-materials-based nanoelectronics requires integration of high-quality dielectric films as a gate insulator. In this work, we explore the integration of organic and inorganic hybrid dielectrics on MoS 2 and study the chemical and electrical properties of these hybrid films. Our atomic force microscopy, X-ray photoelectron spectroscopy (XPS), Raman, and photoluminescence results show that, aside from the excellent film uniformity and thickness scalability down to 2.5 nm, the molecular layer deposition of octenyltrichlorosilane (OTS) and Al 2 O 3 hybrid films preserves the chemical and structural integrity of the MoS 2 surface. The XPS band alignment analysis and electrical characterization reveal that through the inclusion of an organic layer in the dielectric film, the band gap and dielectric constant can be tuned from ∼7.00 to 6.09 eV and ∼9.0 to 4.5, respectively. Furthermore, the hybrid films show promising dielectric properties, including a high breakdown field of ∼7.8 MV/cm, a low leakage current density of ∼1 × 10 -6 A/cm 2 at 1 MV/cm, a small hysteresis of ∼50 mV, and a top-gate subthreshold voltage swing of ∼79 mV/dec. Our experimental findings provide a facile way of fabricating scalable hybrid gate dielectrics on transition metal dichalcogenides for 2D-material-based flexible electronics applications.