Integration of optoelectronic materials with silicon is an important area of study, which could enable silicon CMOS-integrated optical devices for chip-scale optical communication, with the potential for higher bandwidth and lower costs. However, optical-quality III-V thin-film growth on silicon is difficult due to the crystal lattice-mismatch between the materials, and III-V growth typically r...

CdS nanoneedles with different morphologies, structures, and growth modes have been grown on Ni-coated Si(100) surface under different experimental conditions by pulsed laser deposition method. The effects of catalyst layer, substrate temperature, and laser pulse energy on the growth of the CdS nanoneedles were studied in detail. It was confirmed that the formation of the molten catalyst sphere...

We discovered for the first time that light can twist metal to control the chirality of metal nanostructures (hereafter, chiral metal nanoneedles). The helicity of optical vortices is transferred to the constituent elements of the irradiated material (mostly melted material), resulting in the formation of chiral metal nanoneedles. The chirality of these nanoneedles could be controlled by just c...

Plasmonic properties of metal nanostructures are appealing due to their potential to enhance photovoltaics or sensing performance. Our aim was to identify the plasmonic characteristics of silver nanoneedles on a reflective layer in the polarized optical response. Experimental ellipsometry results are complemented by finite-difference time-domain (FDTD) calculations. Plasmon resonances on the na...

Four kinds of nanostructures, nanoneedles, nanohooks, nanorods, and nanotowers of In2O3, have been grown by the vapor transport process with Au catalysts or without any catalysts. The morphology and structure of the prepared nanostructures are determined on the basis of field emission scanning electron microscopy (FESEM), x-ray diffraction (XRD), and transmission electron microscopy (TEM). The ...

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In this paper a new nanostructured support for the culture of cells is presented. The support consists of fields of sharp and high-aspect-ratio nanoneedles. The support is obtained through a specifically developed process that allows controlling the nanoneedles’ densities and height. The nanoneedles are typically 10 μm high with tip diameters under 200 nm. Cell viability on this support was eva...

Nanoneedles display potential in mediating the delivery of drugs and biologicals, as well as intracellular sensing and single-cell stimulation, through direct access to the cell cytoplasm. Nanoneedles enable cytosolic delivery, negotiating the cell membrane and the endolysosomal system, thus overcoming these major obstacles to the efficacy of nanotherapeutics. The low toxicity and minimal invas...

We report the highly stable supercapacitive performance of one-dimensional (1D) nanoneedles of brookite (b) TiO2 synthesized on a conducting glass substrate. The 1D b-TiO2 nanoneedles synthesized over a large area array utilizing hot-filament metal vapor deposition (HFMVD) were 24–26 nm wide, 650 nm long and tapered in a downward direction. X-ray photoemission spectroscopy (XPS) revealed their ...

GaInP/GaAs/Ge triple-junction concentrator solar cells with significant efficiency enhancement were demonstrated with antireflective ZnO nanoneedles. The novel nanostructure was attained with a Zn(NO3)2-based solution containing vitamin C. Under one sun AM 1.5G solar spectrum, conversion efficiency of the triple-junction device was improved by 23.7% via broadband improvement in short-circuit cu...