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Ruthenium (Ru) doped antimony tungstate microflowers, prepared through hydrothermal process, have been investigated for simultaneous adsorption and photocatalysis. The pattern of evolution of microflower structures, however, can be tailored by the synthesis period. This change is observed from the field effect scanning electron microscope and transmission electron microscope images. A possible mechanism behind this morphological change has been developed. An argument based on the zeta potential may be responsible for this distinct morphology due to the strong electrostatic interactions. The variation of a particular x-ray diffraction peak corresponding to the plane { 012 } with variation of Ru doping percentage shows the decrease in crystallinity along the perpendicular direction to this plane. Besides, the optimum Ru doping percentage is evaluated on the basis of photocatalytic efficiency towards methylene blue (MB) degradation under visible light. The highest dye removal efficiency is observed for 2% Ru doped Sb2WO6 (SWO) adsorbing 97% of the MB dye followed by photocatalytic degradation of almost 64% of the remaining dye in 80 min. Furthermore, using different dyes, it is concluded that Ru–SWO showcases high adsorption toward the cationic dyes while it neither adsorbs the anionic dye nor displays photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Fe-based metal-organic frameworks (MOFs) are promising drug delivery materials due to their large surface area, high stability, and biocompatibility. However, their drug loading capacity is constrained by their small pore size, and a further improvement in their drug capacity is needed. In this work, we report an effective and green structural modification strategy to improve drug loading capacity for Fe-based MOFs. Our strategy is to grow MIL-100 (Fe) on carboxylate-terminated polystyrene (PS-COOH) via a sustainable route, which creates a large inner cavity as well as exposure to more functional groups that benefit drug loading capacity. We employ the scanning electron microscope and transmission electron microscope to confirm the hollow structure of MIL-100 (Fe). Up to 30% of drug loading capacity has been demonstrated in our study. We also conduct cell viability tests to investigate its therapeutic effects on breast cancer cells (MDA-MB-231). Confocal laser scanning microscopy imaging confirms cellular uptake and mitochondrial targeting function of doxorubicin-loaded H-M (DOX@H-M) nanoparticles. JC-1 staining of cancer cells reveals a significant change in the mitochondrial membrane potential, indicating the mitochondrial dysfunction and apoptosis of tumor cells. Our study paves the way for the facile synthesis of hollow structural MOFs and demonstrates the potential of applying Fe-based MOFs in breast cancer treatment. [ABSTRACT FROM AUTHOR]

Molten salt electrochemistry is cited as one of the most efficient ways to convert stable but unwanted CO2 into value-added chemical fuels and functional materials, in particular carbon nanotubes (CNTs). In this work, we report the high yield and scalable CO2-deriving CNTs by adding ZnO to molten carbonate electrolyte. The physicochemical properties such as crystal structure, morphology and element composition of the carbon products were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive spectroscopy (EDS), X-ray diffractometer (XRD) and Raman spectrometer (Raman). It is demonstrated that an appropriate amount of ZnO additives can greatly increase the content of CNTs in carbon products. However, the micromorphology and microstructure of the carbon products are found to be significantly changed when the ZnO content is insufficient or excessive. Compared with molten salt electrolyte without ZnO, ZnO-included electrolyte endows CNTs with a higher degree of graphitization and crystallinity. This work demonstrates the feasibility of improving CNTs content in carbon products and lowering required energy for CNTs production by adding ZnO as a promoter. [ABSTRACT FROM AUTHOR]

The primary challenge for the widespread application of two-dimensional (2D) electronics is to achieve satisfactory electrical contacts because, during the traditional metal integration process, difficulties arise due to inevitable physical damage and selective doping. Two-dimensional metal–semiconductor junctions have attracted attention for the potential application to achieve reliable electrical contacts in future atomically thin electronics. Here we demonstrate the van der Waals epitaxial growth of 2D NiTe2-MoS2 metal–semiconductor vertical junctions where the upper NiTe2 selectively nucleates at the edge of the underlying MoS2. Optical microscopy (OM), scanning electron microscopy (SEM), atomic force microscopy (AFM), and scanning transmission electron microscope (STEM) studies confirmed that NiTe2-MoS2 metal–semiconductor vertical junctions had been successfully synthesized. The electrical properties of the NiTe2-contacted MoS2 field-effect transistors (FETs) showed higher field-effect mobilities (μFE) than those with deposited Cr/Au contacts. This study demonstrates an effective pathway to improved MoS2 transistor performance with metal–semiconductor junctions. [ABSTRACT FROM AUTHOR]

ITO nanocrystal-embedded WO3 electrodes (ITO@WO3) have been successfully fabricated with a facile solution process, and the structure and electrochromic properties were studied by transmission electron microscope, scanning electron microscope, X-ray diffraction and electrochemical methods. The results show that moderate embedding of ITO nanocrystals (NCs) effectively improves the electrochromic performance that the optical modulation and coloration efficiency are increased from about 20.86% and 30.18 cm2 C-1 to about 29.37% and 33.49 cm2 C-1, respectively. Further analysis of the cyclic voltammetry and chronoamperometry indicate that the diffusion-controlled reactions associating with the electrochromic of the electrodes are enhanced with the increasing ITO NCs at the low content, while the excessive ITO NCs inhibit them. On the other hand, the capacitive contribution to the total insertion/extraction charges keep steady with various ITO NCs contents in the considering range of the present work, suggesting that ITO NCs affect little on the capacitive nature of the WO3 matrix. These results provide a better understanding of the electrochemical kinetics of the nanocrystal embedded electrodes and are helpful to design more efficient electrochromic devices. [ABSTRACT FROM AUTHOR]

The introduction of heterostructures is a new approach in gas sensing due to their easy and quick transport of charges. Herein, facile hydrothermal and solid-state techniques are employed to synthesize an α-Fe2O3/Nb2O5 heterostructure. The morphology, microstructure, crystallinity and surface composition of the synthesized heterostructures are investigated by scanning electron microscope, transmission electron microscope, x-ray diffraction, x-ray photoelectron spectroscopy and Brunauer–Emmett–Teller analyses. The successful fabrication of the heterostructures was achieved via the mutual incorporation of α-Fe2O3 nanorods with Nb2O5 interconnected nanoparticles (INPs). A sensor based on the α-Fe2O3(0.09)/Nb2O5 heterostructure with a high surface area exhibited enhanced gas-sensing features, maintaining high selectivity and sensitivity, and a considerable recovery percentage towards ethanol gas. The sensing response of the α-Fe2O3(0.09)/Nb2O5 heterostructure at lower operating temperature (160 °C) is around nine times higher than a pure Nb2O5 (INP) sensor at 180 °C with the flow of 100 ppm ethanol gas. The sensors also show excellent selectivity, good long-term stability and a rapid response/recovery time (8s/2s, respectively) to ethanol. The superior electronic conductivity and upgraded sensitivity performance of gas sensors based on the α-Fe2O3(0.09)/Nb2O5 heterostructure are attributed due to its unique structural features, high specific surface area and the synergic effect of the n–n heterojunction. The promising results demonstrate the potential application of the α-Fe2O3(0.09)/Nb2O5 heterostructure as a good sensing material for the fabrication of ethanol sensors. [ABSTRACT FROM AUTHOR]

Diesel soot (DS) collected directly from the exhaust tailpipe of the diesel-powered vehicle was explored for its performance as an electrochemical supercapacitor electrode material. X-ray diffraction and Raman spectroscopy evidenced the existence of graphite carbon form in DS along with low amount of defects in the form of disordered graphite, amorphous carbon, ionic, and polyene impurities. The carbon (C, ~94 at.%) and oxygen (O, ~5 at.%) elements were identified using the X-ray photoelectron spectroscopy technique on the DS surface. The morphology of DS powder consisted of nanoparticles with nearly spherical-shaped morphology as observed under the scanning electron microscope. Further, the transmission electron microscope showed the chain type interconnectivity of DS nanoparticles. The average surface area, average pore radius, and total pore volume of DS were measured to be 88 m² g-1, 1.62 nm, and 0.17 cc g-1, respectively. Cyclic voltammetry and galvanostatic charge-discharge studies were performed to explore the electrochemical behavior of DS slurry-coated electrode. The supercapacitor behavior of DS was studied using various aqueous and organic electrolytes. Higher values of specific capacitance (Csp) were achieved for DS in the case of aqueous electrolytes in comparison to organic electrolytes. The observed highest specific capacitance (Csp) value was 36.77 F g-1 for DS at the current density value of 0.25 A g-1 using 0.5 M H2SO4 electrolyte. DS retains nearly 78.10% of its initial capacitance even after the execution of 5000 cycles, clearly indicating the excellent durability and stability of the material. Thus, DS could be a promising supercapacitor electrode material. [ABSTRACT FROM AUTHOR]

Cost- and resource-efficient growth is necessary for many applications of semiconductor nanowires. We here present the design, operational details and theory behind Aerotaxy, a scalable alternative technology for producing quality crystalline nanowires at a remarkably high growth rate and throughput. Using size-controlled Au seed particles and organometallic precursors, Aerotaxy can produce nanowires with perfect crystallinity and controllable dimensions, and the method is suitable to meet industrial production requirements. In this report, we explain why Aerotaxy is an efficient method for fabricating semiconductor nanowires and explain the technical aspects of our custom-built Aerotaxy system. Investigations using SEM (scanning electron microscope), TEM (transmission electron microscope) and other characterization methods are used to support the claim that Aerotaxy is indeed a scalable method capable of producing nanowires with reproducible properties. We have investigated both binary and ternary III–V semiconductor material systems like GaAs and GaAsP. In addition, common aspects of Aerotaxy nanowires deduced from experimental observations are used to validate the Aerotaxy growth model, based on a computational flow dynamics (CFD) approach. We compare the experimental results with the model behaviour to better understand Aerotaxy growth. [ABSTRACT FROM AUTHOR]

Nanotherapeutics in cancer treatment are dominating global science and research, and have been recognized as the pioneering medical care regimen. Raloxifene (RLN) has been used for its anti-proliferative action on mammary tissue, however, it suffers from poor oral bioavailability. This investigation gives an account of the design and development of RLN-loaded nanostructured lipid carriers (RLN-NLCs) using a simple and scalable ultrasonication method for improved oral efficacy and limited offsite toxicity using Compritol® 888 ATO as a solid lipid and Transcutol® HP as a liquid lipid. In addition, the optimized RLN-NLCs were in the nanometric range (121 nm) with high % entrapment efficiency (%EE) (81%) for RLN, and were further freeze-dried in the presence of mannitol to enhance the stability of RLN-NLCs in the dry state for long-term use. Morphological observation under a transmission electron microscope and scanning electron microscope revealed the spherical smooth surface nanometric size of RLN-NLCs. Powder x-ray diffraction confirmed the encapsulation of RLN into the RLN-NLC's matrix with reduced crystallinity of the drug. The in vitro release study showed a burst release for an initial 4 h, and sustained release for up to 24 h. Furthermore, the RLN-NLCs showed higher cytotoxicity towards MCF-7 cells in vitro in comparison to RLN suspension, and an ex vivo intestinal permeation study demonstrated improved intestinal permeability of RLN-NLCs. Moreover, the in vivo pharmacokinetic study in female Wistar rats showed a 4.79-fold increment in oral bioavailability of RLN from RLN-NLCs compared to RLN suspension. Taken together, our results pave the way for a new nanotherapeutic approach towards breast cancer treatment. [ABSTRACT FROM AUTHOR]

Exploring emergent phenomena in complex oxide heterostructures by interfacial engineering is the frontier of the oxide electronics. The heterointerface formed by oxides with different structures is particularly interesting since symmetry mismatch may produce considerable interface reconstruction and unexpected emergent phenomena. Here, we demonstrate the abnormal magnetic anisotropy in SrFeO2.5/La2/3Ba1/3MnO3/SrFeO2.5 trilayers that are consisted of the perovskite/brownmillerite heterostructures. The compressively strained La2/3Ba1/3MnO3 layer sandwiched between the two SrFeO2.5 layers exhibits in-plane magnetic anisotropy, while the La2/3Ba1/3MnO3 bare film with the same strain state shows perpendicular magnetic anisotropy at low temperature. The high-resolution scanning transmission electron microscope and x-ray absorption spectroscopy analysis reveal the off-center displacement of the Mn ions at interfaces. This would cause a strong orbital reconstruction of Mn ions at the interface and thus the in-plane magnetic anisotropy. This work shows the great potential to explore novel phenomena in artificially designed multilayers by interfacial engineering. [ABSTRACT FROM AUTHOR]

A vanadium bronze nanomaterial, β-Na0.33V2O5, was synthesized using a facile sol-gel method followed by annealing at high temperature. The morphology of the sample was observed using a scanning electron microscope (SEM) and a transmission electron microscope (TEM), and the crystal phase was determined by x-ray diffraction (XRD) spectroscopy. The as-prepared sample displays a morphology of nanorods, and has a pure phase with a high crystallinity. When used as the cathode material for rechargeable lithium batteries, the β-Na0.33V2O5 nanorods fired at 400 °C exhibit better electrochemical properties at a 2.0 V cutoff voltage than those at a 1.5 V cutoff voltage. Over the voltage range of 2.0–4.0 V, they can deliver an initial capacity of 221 mAh g−1 at a 0.5 C rate, and retain 212 mAh g−1 after 200 cycles, accounting for a capacity fading of only 0.02% per cycle. At a 5 C rate, the discharge capacity still reaches 146 mAh g−1, displaying an outstanding rate capability. Control of the electrochemical window is proved to be an effective strategy in boosting the cycling stability of the β-Na0.33V2O5 cathode in this work in spite of a discounted capacity. Results suggest the as-prepared β-Na0.33V2O5 nanorods are promising for use as high-performance cathode materials for rechargeable lithium batteries. [ABSTRACT FROM AUTHOR]

The construction of efficient and stable non-noble metal electrocatalysts for oxygen evolution reaction (OER) is a major challenge via water splitting to make H2 fuel. Herein, we report the hybrids of NiCo bimetallic phosphides (denoted as NixCoy-P) through a one-step phosphidation strategy derived from nanosheets NiCo metal-organic frameworks (NixCoy-BDC). The unique hierarchical porous structure, heterogeneous (Ni2P and Co2P) composition and carbon framework of the NixCoy-P hybrids were characterized by scanning electron microscope, X-ray diffraction and transmission electron microscope, which endowed handy ion diffusion path, synergistically active sites and high conductivity for OER. The as-fabricated Ni1Co1-P catalyst exhibited more excellent OER activity than other phosphides (Ni-P, Ni3Co1-P, Ni1Co3-P and Co-P). More remarkably, the Ni1Co1-P supported on Ni foam (NF) exhibits low overpotential (?35) of 300 mV at a current density of 35 mA cm-2, small Tafel slope of 71 mV dec-1 and excellent stability for OER in 1.0 M KOH solution. This work provides a general strategy to design more efficient multi-metallic component OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Molten carbonate electrolysis demonstrates a feasible approach for the direct transformation of CO2 into reusable carbonaceous substance. In this work, in addition to previously commonly used expensive Li2CO3, alkaline earth carbonates of CaCO3, SrCO3 and BaCO3 which are abundant in nature and of much lower price are employed to combine with Li2CO3 and contribute to the production of valuable carbon nanotubes. Structural features of the synthetic carbon nanotubes are characterized by scanning electron microscope, transmission electron microscope, high resolution transmission electron microscope andX-ray diffractometer. The results demonstrate that galvanostatic electrolysis in pure or alkaline-earth-carbonate-included Li2CO3 provides a high yield of valuable carbon nanotubes production. Alkaline earth carbonate additives produce thicker carbon nanotubes than pure Li2CO3 case, but the lattice distances of the carbon nanotubes electro-deposited in different electrolytes exhibit a good consistency with the standard data of multi-walled carbon nanotubes. Thermodynamic calculations are conducted in order to figure out why alkaline earth carbonate additives prefer thicker carbon nanotubes production. Summarily, this work discloses a rich understanding of how alkaline earth carbonates impact the size of carbon nanotubes and should be helpful to the future size control study. [ABSTRACT FROM AUTHOR]

NiMn2O4 (NMO) nanomaterials were prepared via a facile sol-gel process and small pieces of tissue paper were used as a template to obtain one-dimensional (1D) nanofabric shape. Connectivity of the nanoparticles in fabric shape was observed by field-emission scanning electron microscope and transmission electron microscope images. X-ray diffraction pattern was analyzed to confirm the pure phase and crystallinity of the end product. Energy dispersive X-ray spectroscopywas done to check the homogeneous distribution of the Ni, Mn and O elements. The 1D nanofabric NMO was further employed as an electrode material for supercapacitors (SCs). The cyclic voltammetry, galvanostatic charging/discharging and electrochemical impedance spectroscopy techniques were used to determine the supercapacitive properties of electrode materials. The high specific capacitance of 303 F g-1 was obtained at the current density of 0.5 A g-1. Almost stable specific capacitance was obtained till 5000 cycles. The high specific capacitance and stability of the electrode material may be attributed to the fabric shape and connectivity of the particles where voids/gaps in between particles provide more accommodation for the ions. Asymmetric SC (ASC) device was also fabricated and its electrochemical performance was checked. Two yellow color light-emitting diodes and a motor fan were powered from series-connected two ASCs. [ABSTRACT FROM AUTHOR]

GaN grown on sapphire is electrochemically etched in HF and in KOH. Etching in HF results in a network of nanopillars while that etched in KOH results in a network of pores. The higher density of voids from the network of pores shows the highest strain relaxation for a 1.2μm thick GaN overgrown on the porous templates. In general, a light-emitting diode (LED) on the porous templates gives about 1.5 times higher intensity and a spectral envelop shift towards the red due to a higher In incorporation. The higher intensity is attributed to enhanced light extraction due to light scattering at the voids formed from the pores and improved material quality with dislocation reduction. The formation of larger overgrowth GaN islands which merges to give a continuous GaN film over the porous template reduced the dislocation density and also accounted for higher strain relaxation for the growth of the quantum dots (QDs) and quantum well layers. This reduced the extent of peak shift of LEDs grown on porous GaN template and improved its performance. [ABSTRACT FROM AUTHOR]

A study to analyse beam damage, image quality and edge contrast in the helium ion microscope (HIM) has been undertaken. The sample investigated was graphene. Raman spectroscopy was used to quantify the disorder that can be introduced into the graphene as a function of helium ion dose. The effects of the dose on both freestanding and supported graphene were compared. These doses were then correlated directly to image quality by imaging graphene flakes at high magnification. It was found that a high magnification image with a good signal to noise ratio will introduce very significant sample damage. A safe imaging dose of the order of 1013 He+ cm-2 was established, with both graphene samples becoming highly defective at doses over 5 × 1014 He+ cm-2. The edge contrast of a freestanding graphene flake imaged in the HIM was then compared with the contrast of the same flake observed in a scanning electron microscope and a transmission electron microscope. Very strong edge sensitivity was observed in the HIM. This enhanced edge sensitivity over the other techniques investigated makes the HIM a powerful nanoscale dimensional metrology tool, with the capability of both fabricating and imaging features with sub-nanometre resolution. [ABSTRACT FROM AUTHOR]

We employed an electroless deposition technique to prepare Ni seeds uniformly on a carbon cloth, followed by carbon nanotube (CNT) formation at an elevated temperature. Subsequently, a pulse electrodeposition was used to impregnate PtRu nanoparticles on the CNT structure. Similar procedures were performed on carbon supports including Vulcan XC72R, BP2000, and carbon nanocapsules (CNCs) for comparison purposes. Diffraction patterns from an X-ray confirmed a PtRu alloyed phase. An analysis from inductively coupled plasma-mass spectrometry indicated that the PtRu composition was relatively unchanged. Images from scanning and transmission electron microscopes revealed dense CNTs throughout the carbon cloth with nanoparticulate PtRu evenly impregnated. Considerable PtRu aggregations were found on the CNCs and BP2000. We observed a significantly improved coulomb efficiency and an electrochemically active surface area for the CNT-grown carbon cloth. In both apparent current density and mass activity for methanol electro-oxidation, the CNT-grown carbon cloth revealed the largest values. We attribute the performance enhancement to the large-area CNT structure that allowed facile access of electrolytes. [ABSTRACT FROM AUTHOR]

Water-soluble multiwalled carbon nanotubes (MWNTs) withtemperature-responsive shells were successfully prepared by grafting poly(N-isopropylacrylamide) (PNIPAM) from the sidewalls of MWNTs, via surface reversibleaddition–fragmentation chain transfer (RAFT) polymerization using RAFT agentfunctionalized MWNTs as the chain transfer agent. Thermogravimetric analysis (TGA)measurements showed that the weight composition of the as-grown PNIPAM polymers onthe MWNTs can be well controlled by the feed ratio (in weight) of NIPAM to RAFT agentfunctionalized MWNTs (MWNT-SC(S)Ph). The MWNT-g-PNIPAM has good solubility inwater, chloroform, and tetrahydrofuran (THF). Transmission electron microscope (TEM)and scanning electron microscope (SEM) images also showed that the MWNT-g-PNIPAMwas dispersed individually and eventually bonded with the polymer layer by surface RAFTpolymerization. The PNIPAM shell is very sensitive to a change of temperature. Thismethod could find potential applications by grafting other functional polymer chains ontoMWNTs. [ABSTRACT FROM AUTHOR]

The oxide shell of Al nanoparticles (Al NPs) prevents further reaction of Al/CuO nanothermites which reduces Al utilization efficiency and the performance of the nanothermites. However, the performance of Al/CuO nanothermites can be improved by adding ammonium perchlorate (AP). In this work, in order to confirm and explain the enhancement mechanism of AP on Al/CuO nanothermites, Al/CuO/NC and Al/CuO/NC/AP composites were prepared using the electrospray method. The composites were characterized by differential scanning calorimetry/thermogravimetric, x-ray diffraction, scanning electron microscope and transmission electron microscopy. Meanwhile, the ignition temperature and the time-resolved analysis of the rapid pyrolysis chemistry of the composites were tested using T-jump and time-of-flight mass spectrometry, respectively. The results show that Al NPs of Al/CuO/NC/AP composite are hollow compared to Al/CuO/NC composite after reaction. Al NPs and CuO NPs reduce the decomposition temperature and facilitate the rapid decomposition of the AP, and the decomposition products of the AP can destroy the oxidation layer of Al NPs. This result facilitates the further conduct of the thermite reaction. A mutually reinforcing relationship exists between the Al/CuO/NC composites and AP. [ABSTRACT FROM AUTHOR]

This study applied the combination of plasma-activated water (PAW) and mild heat (40 °C and 55 °C) for the decontamination of Bacillus cereus spores in rice (Oryza sativa L. ssp. japonica). In this study, PAW combined with 40 °C and 55 °C (PAW-40 and PAW-55) achieved 1.54 and 2.12 log10 CFU g−1 reductions of B. cereus spores in rice after 60 min exposure, which was significantly higher than the inactivation level (0.72 log10 CFU g−1) induced by PAW treatment alone. The assays for the leakage of intracellular contents (nucleic acids, proteins, dipicolinic acid-DPA) and the propidium iodide (PI) fluorescence probe confirmed that the combination of PAW and mild heat caused significant damages on the intact multilayered structure of B. cereus spores than the individual PAW did. The application of scanning electron microscope (SEM) and transmission electron microscope (TEM) provided a direct observation for the visible disruption of external structure and leakage of intracellular components caused by the combination of PAW and mild heat. Besides, the combination of PAW and mild heat caused no adverse effect on the texture and sensory qualities of the rice after cooking. These findings provide some knowledge for the application of PAW combined with mild heat for the decontamination of spores in rice. [ABSTRACT FROM AUTHOR]

An effective surface enhanced Raman scattering (SERS) substrate is designed and fabricated by synthesis of SiO2 nanorods array via glancing angle deposition, followed by coating Au nanoparticles onto SiO2 surface in order to create numerous “hot spots”. The detecting sensitivity of such substrate could be optimized by simply adjusting the deposition time of Au. Thus, it can be used for detection of Rhodamine 6G at concentration as low as 10−9 M. Furthermore, our SERS substrate is applied to detect 5 μg/g polychlorinated biphenyls in soil sample, which proves its potential for trace environmental pollutants detection. [ABSTRACT FROM AUTHOR]

Solid-state nanopores of only a few nanometres in size show a great potential for applications such as molecule detection and DNA sequencing. In most cases, the fabrication of such a nanopore requires the high energy beam of a transmission electron microscope (TEM) or focused ion beam (FIB) tool to drill or reshape a small hole in a freestanding membrane. Here, we present a novel method to reduce the size of existing nanopores using electron-beam-induced deposition (EBID) of carbon in a conventional scanning electron microscope (SEM). The existing nanopores are etched in a silicon membrane using anisotropic wet etching and can be shrunk down to a few nanometres using EBID. This paper discusses the parameters that influence the rate of shrinking and provides an insight into the underlying mechanism. [ABSTRACT FROM AUTHOR]

An activated-carbon (AC) assisted route is developed to synthesize a ZnO nanoparticle network. The route involves simple addition of AC to the solution containing the zinc salt and finally removing them by burning at higher temperature to form a sponge-like porous ZnO nanoparticles. The surface area measurements show that AC-assisted ZnO nanoparticles (AC-ZnO) have a higher surface area than those synthesized without AC (B-ZnO), which is further confirmed by the field emission scanning electron microscope (FESEM) and high resolution transmission electron microscope (HRTEM) images. Ultraviolet (UV) absorbance results show that the optical quality remains almost unchanged for both types of nanoparticles. Enhanced and faster UV photosensitivity has been observed for the AC-ZnO. The change in the UV photosensing properties demonstrated here provides a new approach to synthesizing other high surface area materials for novel physical and chemical properties. [ABSTRACT FROM AUTHOR]

The results of numerical simulations of nanometer precision distributions of microscopic ion fluxes in ion-assisted etching of nanoscale features on the surfaces of dielectric materials using a self-assembled monolayer of spherical nanoparticles as a mask are presented. It is shown that the ion fluxes to the substrate and nanosphere surfaces can be effectively controlled by the plasma parameters and the external bias applied to the substrate. By proper adjustment of these parameters, the ion flux can be focused onto the areas uncovered by the nanospheres. Under certain conditions, the ion flux distributions feature sophisticated hexagonal patterns, which may lead to very different nanofeature etching profiles. The results presented are generic and suggest viable ways to overcome some of the limitations of the existing plasma-assisted nanolithography. [ABSTRACT FROM AUTHOR]

We report the growth of ultralong b-Ga2O3 nanowires and nanobelts on silicon substrates using a vapor phase transport method. The growth was carried out in a tube furnace, with gallium metal serving as the gallium source. The nanowires and nanobelts can grow to lengths of hundreds of nanometers and even millimeters. Their full lengths have been captured by both scanning electron microscope (SEM) and optical images. X-ray diffraction (XRD) patterns and transmission electron microscope (TEM) images have been used to study the crystal structures of these nanowires and nanobelts. Strong blue emission from these ultralong nanostructures can be readily observed by irradiation with an ultraviolet (UV) lamp. Diffuse reflectance spectroscopy measurements gave a band gap of 4.56 eV for these nanostructures. The blue emission shows a band maximum at 470 nm. Interestingly, by annealing the silicon substrates in an oxygen atmosphere to form a thick SiO2 film, and growing Ga2O3 nanowires over the sputtered gold patterned regions, horizontal Ga2O3 nanowire growth in the non-gold-coated regions can be observed. These horizontal nanowires can grow to as long as over 10 µm in length. Their composition has been confirmed by TEM characterization. This represents one of the first examples of direct horizontal growth of oxide nanowires on substrates. [ABSTRACT FROM AUTHOR]