Mechanism of WS Nanotube Formation Revealed by / Imaging.

Multiwall WS nanotubes have been synthesized from WO nanowhiskers in substantial amounts for more than a decade. The established growth model is based on the "surface-inward" mechanism, whereby the high-temperature reaction with HS starts on the nanowhisker surface, and the oxide-to-sulfide conversion progresses inward until hollow-core multiwall WS nanotubes are obtained. In the present work, an upgraded SEM μReactor with H and HS sources has been conceived to study the growth mechanism in detail.

WO Nanowhiskers Decorating SiO Nanofibers: Lessons from SEM/TEM Growth to Large Scale Synthesis and Fundamental Structural Understanding.

Tungsten suboxide WO nanowhiskers are a material of great interest due to their potential high-end applications in electronics, near-infrared light shielding, catalysis, and gas sensing. The present study introduces three main approaches for the fundamental understanding of WO nanowhisker growth and structure. First, WO nanowhiskers were grown from γ-WO/-SiO nanofibers in a scanning electron microscope (SEM) utilizing a specially designed microreactor (μReactor).

Real-Time Study of Surface-Guided Nanowire Growth by Scanning Electron Microscopy.

Surface-guided growth has proven to be an efficient approach for the production of nanowire arrays with controlled orientations and their large-scale integration into electronic and optoelectronic devices. Much has been learned about the different mechanisms of guided nanowire growth by epitaxy, graphoepitaxy, and artificial epitaxy. A model describing the kinetics of surface-guided nanowire growth has been recently reported.

Surface Modification of Metallic Inserts for Enhancing Adhesion at the Metal-Polymer Interface.

A combination of mechanical and chemical treatments was utilized to modify the surface textures of copper and duralumin inserts in order to enhance the adhesion at the metal-polymer interface and provide an adhesive joint with a high loadbearing capacity. Pretreatment of the surfaces with sandblasting was followed by etching with various chemical mixtures. The resulting surface textures were evaluated with a scanning electron microscope (SEM) and an optical confocal microscope.

Preparation of Textured Surfaces on Aluminum-Alloy Substrates.

The ways of producing porous-like textured surfaces with chemical etching on aluminum-alloy substrates were studied. The most appropriate etchants, their combination, temperature, and etching time period were explored. The influence of a specifically textured surface on adhesive joints' strength or superhydrophobic properties was evaluated.

Silicon oxide nanowire growth mechanisms revealed by real-time electron microscopy.

Growth of one-dimensional materials is possible through numerous mechanisms that affect the nanowire structure and morphology. Here, we explain why a wide range of morphologies is observed when silicon oxide nanowires are grown on silicon substrates using liquid gallium catalyst droplets. We show that a gallium oxide overlayer is needed for nanowire nucleation at typical growth temperatures, and that it can decompose during growth and, hence, dramatically alter the nanowire morphology.