Embedded nanostructures Revealed in Three Dimensions

Coherently Embedded Ag Nanostructures in Si: 3D Imaging and

Figure 2 (a) shows a low magnification cross-sectional TEM (X-TEM) bright field (BF) image of as-deposited 2 nm Ag/17 nm GeOx/SiOx/Si(100). This confirms the presence of spherical silver nanoparticles on top of an amorphous GeOx layer. It should be noted that a physical vapor deposition of Ge in high vacuum condition yielded GeOx layer. The as-deposited Ag thin film showed isolated irregular nanostructures. From figure 2 (a), the thicknesses of the GeOx and the native oxide (SiOx) layers were found to be ≈17 nm and ≈2 nm, respectively. Figure 2 (b) depicts a low magnification BF X-TEM micrograph of 2 nm Ag/17 nm GeOx/SiOx/Si (100) at ≈800°C (annealing done in air for 30 minutes). From this micrograph, the thickness of GeOx is found to be ≈75 nm where SiOx is ≈20 nm thick. Following the annealing in air, the GeOx and SiOx layer thicknesses have been increased by a factor of ≈3.4 and ≈9, respectively. The cross-sectional image taken (for 2 nm Ag/17 nm GeOx/SiOx/Si(100) @800°C), shown in figure 2 (b), confirms the intrusion of silver into the silicon substrate. Figure 2 (c) represents a high resolution lattice image of a small area shown in Figure 2 (b). This lattice image confirms the presence of Ag (111) (0.238 ± 0.005 nm) and Si (111) (0.315 ± 0.005 nm) lattice planes as an endotaxial structure.STEM- EDX Elemental of mapping 2[emsp14]nm Ag/17[emsp14]nm GeOx/SiOx/Si (100) @800[deg]C (a) STEM Micrograph, (b) Oxygen mapping, (c) Silicon mapping, (d),(e) Germanium K,L mapping and (e) Silver mapping. nostructures in silicon. The Moiré fringe spacing can be determined by

where d1, d2 are lattice spacings of the planes which are constituents of Moiré fringes and β is the angle between the planes. The Moiré fringe spacing of 0.96 nm was calculated between Ag(111) and Si(111) planes with β = 0. This matches well with the measured fringe spacing from our measurements (Figure 2 (c)) is 0.95 ± 0.01 nm. Figure 2 (d) is the synchrotron XRD spectrum of the 2 nm Ag/17 nm GeOx/SiOx/Si(100) @800°C in air for 30 minutes, which depicts the single crystalline nature of the silver nanostructures on silicon (100) substrate. In the XRD spectrum, only Ag(002) and Ag(004) peaks were observed along with the Si(004) peak that belongs to the substrate. Due to the larger x-ray beam size (250 μm × 250 μm), the XRD show the macroscopic ordering. Hence, the XRD data confirms the presence of crystalline Ag structures over a larger scale compared to TEM. The inset of figure 2(d) shows the selected area electron diffraction (SAED) pattern taken on a single endotaxial nanostructure, confirming that the silver nanostructures are single crystalline in nature. XRD and SAED confirm the macroscopic and microscopic coherent nature of the Ag nanostructures, respectively.

Figure 2: X-TEM Micrographs of 2 nm Ag/17 nm GeOx/SiOx/Si (100) (a) Low Mag of as-deposited (b) Low Mag of 800 °C annealed in air (c) HR-XTEM depicts endotaxial structures (with Moire fringes) and (d) X-Ray Diffraction Pattern showing the single crystalline nature of the Ag nano structures which also complimented by a Selected Area Electron Diffraction (SAD) pattern taken on a single structure.

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Paper battery?

by edsdesk

Mon Dec 7, 4:28 pm ET
WASHINGTON (Reuters) – Ordinary paper could one day be used as a lightweight battery to power the devices that are now enabling the printed word to be eclipsed by e-mail, e-books and online news.
Scientists at Stanford University in California reported on Monday they have successfully turned paper coated with ink made of silver and carbon nanomaterials into a "paper battery" that holds promise for new types of lightweight, high-performance energy storage.
The same feature that helps ink adhere to paper allows it to hold onto the single-walled carbon nanotubes and silver nanowire films

Some ... some not.

by setArcos

Biotechnology, bioinformatics
Emerging technology
Genetic engineering
Synthetic biology, synthetic genomics
Artificial photosynthesis
Anti-aging drugs: resveratrol, SRT1720
Vitrification or cryoprotectant
Hibernation or suspended animation
Stem cell treatments
Personalized medicine
Body implants, prosthesis
In vitro meat
Regenerative medicine
[edit] Energy systems
Emerging technology
Concentrated solar power includes thermal

Nanotubes Increase Solar PV Conductivity 100 Million-Fold  — Sourceable
Carbon-based nanostructures are already being used as materials in solar cells with increasing frequency, yet their ability to enhance electrical performance has thus far been hampered by limited ability to assemble orderly networks using the materials.

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