Plasmonic nanostructures for surface enhanced spectroscopic methods

The development within the last five years in the field of surface enhanced spectroscopy methods was comprehensively reviewed.

Monodisperse inorganic supraparticles: formation mechanism, properties and applications

Monodisperse inorganic supraparticles (SPs) are an emerging and hot research topic in the chemistry, physics and materials science communities in the past several years. Monodisperse inorganic SPs exhibit unique physiochemical properties due to their well-defined shape and distinctive topological structure. This review summarizes recent progress in the study of formation mechanism, properties and applications of inorganic monodisperse SPs. The future developments in this research area are also discussed.

Characterisation of surface wettability based on nanoparticles

Nanoparticles are becoming frequently used in the research area of creating functional surfaces because they can be more versatile than just making dimensions smaller. Particularly, a variety of nanoparticles have been applied for the construction of superhydrophobic and superhydrophilic surfaces with micro- and nano-scaled structures. As nanoparticles can also be fashioned and modified, their effects will be of great importance to the formed surface structures. In the present paper, we review the recent research progress in the utilization of nanoparticles to form extremely wettable/non-wettable surface structures and their influence on surface wettability. This report manifests an apparent inclination of nanoparticle structured surfaces using the multidisciplinary approaches, from the viewpoint of engineer/scientist. Therefore, the typical methodologies with regard to the use of nanoparticles, including the preparation and functionalisation processes, for the realization of surface wettabilities are discussed in this work. The discussions also represent some of the size-determined phenomena that are related to wettable/non-wettable surfaces. This Review thus provides an insight into the connection between nanoparticles and surface wettability.

A unique solid-solid transformation of silver nanoparticles on reactive ion-etching-processed silicon

Processes that combine nanoparticle suspensions with micromechanical or microelectronics platforms can reveal new phenomena unique to nanoscale objects. We report that silver nanoparticles react with silicon wafers that have been patterned by reactive ion etching (RIE) in SF(6)/O(2) plasma. This reaction results in the localized deposition of silver on the patterns. Through the modification of the reaction conditions, the reaction mechanism was explored. Redeposition of the sputtered RIE products is suggested as the key to this transformation. The new silver deposition process was utilized to localize the growth of gold nanoparticles and silicon nanowires on the vertical sidewalls of patterns in silicon, demonstrating a simple route to the fabrication of overhanging nanoscale objects.

One-pot synthesis of liquid Hg/solid β-HgS metal-semiconductor heterostructures with unique electrical properties

Liquid metal-solid semiconductor heterostructures, Hg heads combined with single-crystalline β-HgS tails, with controllable sizes and well-defined interfaces have been fabricated for the first time via one-pot synthesis. Such heterostructures can exist in water with good stability due to coordination adsorption of cysteine molecules onto the surface of both Hg and HgS through Hg-S bonds. Two-probe current-voltage curve measurements reveal that good ohmic contacts without additional resistance contacts are generated at the interfaces of Hg/β-HgS heterostructures. Only existence of ohmic contacts offers many potential applications of metal-semiconductor heterostructures in minimization of electronic devices.