A common misconception is that the irradiation of solids with energetic electrons and ions has exclusively detrimental effects on the properties of target materials. In addition to the well-known cases of doping of bulk semiconductors and ion beam nitriding of steels, recent experiments show that irradiation can also have beneficial effects on nanostructured systems. Electron or ion beams may serve as tools to synthesize nanoclusters and nanowires, change their morphology in a controllable manner, and tailor their mechanical, electronic, and even magnetic properties. Harnessing irradiation as a tool for modifying material properties at the nanoscale requires having the full microscopic picture of defect production and annealing in nanotargets. In this article, we review recent progress in the understanding of effects of irradiation on various zero-dimensional and one-dimensional nanoscale systems, such as semiconductor and metal nanoclusters and nanowires, nanotubes, and fullerenes. We also consider the t...

Ion and electron irradiation-induced effects in nanostructured materials

Progress in discovery and structural design of color conversion phosphors for LEDs

This review covers advances in electrochemical and biochemical sensor development and usage during 2010 and 2011 In choosing scholarly articles to contribute to this review, special emphasis was placed on work published in the areas of reference electrodes, potentiometric sensors, voltammetric sensors, amperometric sensors, biosensors, immunosensors, and mass sensors In the past two years there have been a number of important papers, that do not fall into the general subsections contained within the larger sections Such novel advances are very important for the field of electrochemical sensors as they open up new avenues and methods for future research Each section above contains a subsection titled “Other Papers of Interest” that includes such articles and describes their importance to the field in general For example, while most electrochemical techniques for sensing analytes of interest are based on the changes in potential or current, Shan et al1 have developed a completely novel method for performing electrochemical measurements In their work, they report a method for imaging local electrochemical current using the optical signal of the electrode surface generated from a surface plasmon resonance (SPR) The electrochemical current image is based on the fact that the current density can be easily calculated from the local SPR signal The authors demonstrated this concept by imaging traces of TNT on a fingerprint on a gold substrate

Full articles and reviews were primarily amassed by searching the SciFinder Scholar and ISI Web of Knowledge Additional articles were found through alternate databases or by perusing analytical journals for pertinent publications Due to the reference limitation, only publications written in English were considered for inclusion Obviously, there have been more published accounts of groundbreaking work with electrochemical and biochemical sensors than those covered here This review is a small sampling of the available literature and not intended to cover every advance of the past two years The literature chosen focuses on new trends in materials, techniques, and clinically relevant applications of novel sensors To ensure proper coverage of these trends, theoretical publications and applications of previously reported sensor development were excluded

We want to remind our readers that this review is not intended to provide comprehensive coverage of electrochemical sensor development, but rather to provide a glimpse of the available depth of knowledge published in the past two years This review is meant to focus on novel methods and materials, with a particular focus on the increasing use of graphene sheets for sensor material development For readers seeking more information on the general principles behind electrochemical sensors and electrochemical methods, we recommend other sources with a broader scope2, 3 Electrochemical sensor research is continually providing new insights into a variety of fields and providing a breadth of relevant literature that is worthy of inclusion in this review Unfortunately, it is impossible to cover each publication and unintentional oversights are inevitable We sincerely apologize to the authors of electrochemical and biochemical sensor publications that were inadvertently overlooked

Electrochemical Sensors and Biosensors

A novel non-enzymatic glucose sensor based on Cu nanoparticle modified graphene sheets electrode.

Chirality in nanoscience may offer new opportunities for applications beyond the traditional fields of chirality, such as the asymmetric catalysts in the molecular world and the chiral propellers in the macroscopic world. In the last two decades, there has been an amazing array of chiral nanostructures reported in the literature. This review aims to explore and categorize the common mechanisms underlying these systems. We start by analyzing the origin of chirality in simple systems such as the helical spring and hair vortex. Then, the chiral nanostructures in the literature were categorized according to their material composition and underlying mechanism. Special attention is paid to highlight systems with original discoveries, exceptional structural characteristics, or unique mechanisms.

Emerging chirality in nanoscience

Control of competing parameters such as thermoelectric (TE) power and electrical and thermal conductivities is essential for the high performance of thermoelectric materials. Bulk-nanocomposite materials have shown a promising improvement in the TE performance due to poor thermal conductivity and charge carrier filtering by interfaces and grain boundaries. Consequently, it has become pressingly important to understand the formation mechanisms, stability of interfaces and grain boundaries along with subsequent effects on the physical properties. We report here the effects of the thermodynamic environment during spark plasma sintering (SPS) on the TE performance of bulk-nanocomposites of chemically synthesized Bi2Te2.7Se0.3 nanoplatelets. Four pellets of nanoplatelets powder synthesized in the same batch have been made by SPS at different temperatures of 230, 250, 280, and 350 °C. The X-ray diffraction, transmission electron microscopy, thermoelectric, and thermal transport measurements illustrate that the ...

Interface driven energy filtering of thermoelectric power in spark plasma sintered Bi(2)Te(2.7)Se(0.3) nanoplatelet composites.

Ultraviolet electroluminescence was demonstrated at room temperature from a ZnO rod homojunction light-emitting diode array The p-type doping was realized by phosphorous (P) ion implantation into defect-free ZnO rods followed by annealing High resolution transmission electron microscopy shows the lattice compression of annealed single crystalline P-doped ZnO rod compared to the as-grown ZnO rod, suggesting atomically incorporation of P into the ZnO wurtzite structure p-type doping was confirmed by low temperature photoluminescence spectra and single rod current-voltage characterization

https://dr.ntu.edu.sg/bitstream/10220/6882/1/27. ultraviolet emission from a zno rod homojunction light-emitting diode.pdf

Ultraviolet emission from a ZnO rod homojunction light-emitting diode

Through the PO43− groups regularly arranged on its sugar-phosphate backbone, DNA is used to direct the growth of a network structure of ultrasmall FePO4 nanoparticles on double-wall carbon nanotubes. The resulting structure has achieved nearly 100% theoretical storage capacity for the FePO4 active component as a cathode in lithium-ion batteries.

DNA-directed growth of FePO4 nanostructures on carbon nanotubes to achieve nearly 100% theoretical capacity for lithium-ion batteries

A thin-walled graphitic nanocages material with well-developed graphitic structure, large specific surface area and pronounced mesoporosity was synthesized and used to construct a sensing interface for an amperometric glucose biosensor, showing a high and reproducible sensitivity of 13.3 μA mM−1 cm−2, linear dynamic range of 0.02−6.2 mM, and fast response time of 5 s. It was successfully used to accurately detect glucose in human serum with effective discrimination to common interference species such as dopamine, ascorbic acid, acetaminophen, and uric acid.

Thin-walled graphitic nanocages as a unique platform for amperometric glucose biosensor

Intense near-infrared (NIR) emission around 1534 nm has been obtained from ZnO-SiO2:Er 3+ composites upon broadband ultraviolet light excitation. Remarkably, enhancement of the NIR emission as much as 20 times was achieved by optimal codoping with Li + ions. To elucidate the relevant mechanisms, comprehensive spectroscopic measurements have been performed on ZnO-SiO2 composites with and without Er 3+ ions doping. Photoluminescence spectroscopy and fluorescence decay dynamics clearly verify the efficient energy transfer from ZnO quantum dots (QDs) to Er 3+ ions. Our results have not only demonstrated an efficient approach of color down-conversion but also indicated that ZnO-SiO2:Er 3+ composites could be a promising material for optical amplifier using broadband UV pumping.

/pdf/efficient-energy-transfer-and-enhanced-infrared-emission-in-2vyobzy684.pdf

Yiqiang Shen

Papers

Interface driven energy filtering of thermoelectric power in spark plasma sintered Bi(2)Te(2.7)Se(0.3) nanoplatelet composites.

Ultraviolet emission from a ZnO rod homojunction light-emitting diode

DNA-directed growth of FePO4 nanostructures on carbon nanotubes to achieve nearly 100% theoretical capacity for lithium-ion batteries

Thin-walled graphitic nanocages as a unique platform for amperometric glucose biosensor

Efficient Energy Transfer and Enhanced Infrared Emission in Er-Doped ZnO-SiO2 Composites