Multiscale fibril structure of hollow windmill palm fibers

Windmill palm fiber is a kind of multicellular lignocellulose fiber material. Multiscale structure is an essential factor in mechanical properties and applications. The multiscale fibrils under sulfuric acid treatment had been prepared to improve the understanding of the macro-, micro-, and nanoscale structure of the windmill palm fiber. Scanning electron microscopy, atomic force microscopy, wide-angle X-ray scattering, and X-ray diffraction were used to analyze these samples’ structure. Furthermore, the result showed that the elementary fibril diameter was 4–10 nm, whereas that of the microfibrils was 20–70 nm. The diameters of macrofibril and macrofibril bundles were 0.4–1.0 µm and 1.2–5.5 µm, respectively. The elementary fibril assembled into spiral microfibril with an angle of 46°. The crystallinity of nanofibril extracted from windmill palm fiber was about 62%.

Download Full-text

Nanoengineering of Gold Nanoparticles: Green Synthesis, Characterization, and Applications

Crystals ◽

10.3390/cryst9120612 ◽

2019 ◽

Vol 9 (12) ◽

pp. 612 ◽

Cited By ~ 2

Author(s):

Nancy Tepale ◽

Víctor V. A. Fernández-Escamilla ◽

Clara Carreon-Alvarez ◽

Valeria J. González-Coronel ◽

Adan Luna-Flores ◽

...

Keyword(s):

Gold Nanoparticles ◽

Green Synthesis ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

Fundamental Study ◽

X Ray ◽

Force Microscopy ◽

X Ray Scattering ◽

Atomic Force ◽

Transmission Electron

The fundamental aspects of the manufacturing of gold nanoparticles (AuNPs) are discussed in this review. In particular, attention is devoted to the development of a simple and versatile method for the preparation of these nanoparticles. Eco-friendly synthetic routes, such as wet chemistry and biosynthesis with the aid of polymers, are of particular interest. Polymers can act as reducing and/or capping agents, or as soft templates leading to hybrid nanomaterials. This methodology allows control of the synthesis and stability of nanomaterials with novel properties. Thus, this review focus on a fundamental study of AuNPs properties and different techniques to characterize them, e.g., Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), UV-Visible spectroscopy, Dynamic Light Scattering (DLS), X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy, Small-angle X-Ray Scattering (SAXS), and rheology. Recently, AuNPs obtained by “green” synthesis have been applied in catalysis, in medicine, and as antibacterials, sensors, among others.

Download Full-text

Investigation of the Effect of Uv-Assisted Oxidation and Nitridation of Hafnium Metal Films

MRS Proceedings ◽

10.1557/proc-780-y5.5 ◽

2003 ◽

Vol 780 ◽

Author(s):

C. Essary ◽

V. Craciun ◽

J. M. Howard ◽

R. K. Singh

Keyword(s):

Uv Radiation ◽

Photoelectron Spectroscopy ◽

Grazing Angle ◽

X Ray Diffraction ◽

Metal Thin Films ◽

X Ray ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Silicon Interface

AbstractHf metal thin films were deposited on Si substrates using a pulsed laser deposition technique in vacuum and in ammonia ambients. The films were then oxidized at 400 °C in 300 Torr of O2. Half the samples were oxidized in the presence of ultraviolet (UV) radiation from a Hg lamp array. X-ray photoelectron spectroscopy, atomic force microscopy, and grazing angle X-ray diffraction were used to compare the crystallinity, roughness, and composition of the films. It has been found that UV radiation causes roughening of the films and also promotes crystallization at lower temperatures.Furthermore, increased silicon oxidation at the interface was noted with the UVirradiated samples and was shown to be in the form of a mixed layer using angle-resolved X-ray photoelectron spectroscopy. Incorporation of nitrogen into the film reduces the oxidation of the silicon interface.

Download Full-text

Low Molecular Weight Microfibers with Light Sensing Properties

Materiale Plastice ◽

10.37358/mp.17.4.4920 ◽

2017 ◽

Vol 54 (4) ◽

pp. 655-658

Author(s):

Andrei Bejan ◽

Dragos Peptanariu ◽

Bogdan Chiricuta ◽

Elena Bicu ◽

Dalila Belei

Keyword(s):

Molecular Weight ◽

Low Molecular Weight ◽

X Ray Diffraction ◽

Aromatic Rings ◽

X Ray ◽

Force Microscopy ◽

Light Sensing ◽

Sensing Applications ◽

Atomic Force ◽

Low Molecular Weight Compounds

Microfibers were obtained from organic low molecular weight compounds based on heteroaromatic and aromatic rings connected by aliphatic spacers. The obtaining of microfibers was proved by scanning electron microscopy. The deciphering of the mechanism of microfiber formation has been elucidated by X-ray diffraction, infrared spectroscopy, and atomic force microscopy measurements. By exciting with light of different wavelength, florescence microscopy revealed a specific optical response, recommending these materials for light sensing applications.

Download Full-text

Probing the Room Temperature Deuterium Absorption Kinetics in Nanoscale Magnesium Based Hydrogen Storage Multilayers Using Neutron Reflectometry, X-ray Diffraction, and Atomic Force Microscopy

The Journal of Physical Chemistry C ◽

10.1021/jp209296b ◽

2012 ◽

Vol 116 (9) ◽

pp. 5868-5880 ◽

Cited By ~ 15

Author(s):

W.P. Kalisvaart ◽

E.J. Luber ◽

E. Poirier ◽

C.T. Harrower ◽

A. Teichert ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Hydrogen Storage ◽

Room Temperature ◽

Neutron Reflectometry ◽

Absorption Kinetics ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force

Download Full-text

Nanocrystalline Solutions as Precursors to The Spray Deposition of Cdte Thin Films

MRS Proceedings ◽

10.1557/proc-382-461 ◽

1995 ◽

Vol 382 ◽

Cited By ~ 4

Author(s):

Martin Pehnt ◽

Douglas L. Schulz ◽

Calvin J. Curtis ◽

Helio R. Moutinho ◽

Amy Swartzlander ◽

...

Keyword(s):

Thin Films ◽

Atomic Force Microscopy ◽

Grain Size ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Cdte Nanoparticles ◽

Atomic Force ◽

Vis Spectroscopy ◽

Cdte Thin Films

ABSTRACTIn this article we report the first nanoparticle-derived route to smooth, dense, phase-pure CdTe thin films. Capped CdTe nanoparticles were prepared by injection of a mixture of Cd(CH3)2, (n-C8H17)3 PTe and (n-C8H17)3P into (n-C8H17)3PO at elevated temperatures. The resultant nanoparticles 32-45 Å in diameter were characterized by x-ray diffraction, UV-Vis spectroscopy, transmission electron microscopy, thermogravimetric analysis and energy dispersive x-ray spectroscopy. CdTe thin film deposition was accomplished by dissolving CdTe nanoparticles in butanol and then spraying the solution onto SnO2-coated glass substrates at variable susceptor temperatures. Smooth and dense CdTe thin films were obtained using growth temperatures approximately 200 °C less than conventional spray pyrolysis approaches. CdTe films were characterized by x-ray diffraction, UV-Vis spectroscopy, atomic force microscopy, and Auger electron spectroscopy. An increase in crystallinity and average grain size as determined by x-ray diffraction was noted as growth temperature was increased from 240 to 300 °C. This temperature dependence of film grain size was further confirmed by atomic force microscopy with no remnant nanocrystalline morphological features detected. UV-Vis characterization of the CdTe thin films revealed a gradual decrease of the band gap (i.e., elimination of nanocrystalline CdTe phase) as the growth temperature was increased with bulk CdTe optical properties observed for films grown at 300 °C.

Download Full-text

In situ X-ray Scattering Study of the Formation of Au Nano Crystals During Thermal Annealing

MRS Proceedings ◽

10.1557/proc-1027-d07-04 ◽

2007 ◽

Vol 1027 ◽

Author(s):

Do Young Noh ◽

Ki-Hyun Ryu ◽

Hyon Chol Kang

Keyword(s):

Thermal Annealing ◽

Bragg Reflection ◽

Ex Situ ◽

X Ray ◽

Force Microscopy ◽

X Ray Scattering ◽

Atomic Force ◽

Au Thin Films ◽

Ray Scattering

AbstractThe transformation of Au thin films grown on sapphire (0001) substrates into nano crystals during thermal annealing was investigated by in situ synchrotron x-ray scattering and ex situ atomic force microscopy (AFM). By monitoring the Au(111) Bragg reflection and the low Q reflectivity and comparing them with ex situ AFM images, we found that polygonal-shape holes were nucleated and grow initially. As the holes grow larger and contact each other, their boundary turns into Au nano crystals. The Au nano crystals have a well-defined (111) flat top surface and facets in the in-plane direction.

Download Full-text

Frequency and Temperature Dependence of Dielectric Properties of Orthorhombic HoMnO3 Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1025-1026.427 ◽

2014 ◽

Vol 1025-1026 ◽

pp. 427-431

Author(s):

Ping Gao ◽

Wei Zhang ◽

Wei Tian Wang

Keyword(s):

Dielectric Properties ◽

Pulsed Laser ◽

Signal Amplitude ◽

Debye Model ◽

Laser Deposition ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Cole Diagram

Orthorhombic HoMnO3 films were prepared epitaxially on Nb-doped SrTiO3 single crystal substrates by using pulsed laser deposition technique. The films showed perfectly a-axis crystallographic orientations. X-ray diffraction and atomic force microscopy were used to characterize the films. The complex dielectric properties were measured as functions of frequency (40 Hz~1 MHz) and temperature (80 K~300 K) with a signal amplitude of 50 mv. The respective dielectric relaxation peaks shifted to higher frequency as the measuring temperature increased, with the same development of real part of the complex permittivity. The cole-cole diagram was obtained according to the Debye model, and the effects of relaxation process were discussed.

Download Full-text

Lateral Size of Self-Patterned Nanostructures Controlled by Multi-Step Deposition

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.106.117 ◽

2005 ◽

Vol 106 ◽

pp. 117-122 ◽

Cited By ~ 3

Author(s):

Izabela Szafraniak ◽

Dietrich Hesse ◽

Marin Alexe

Keyword(s):

Electron Microscopy ◽

Ultrathin Films ◽

Lateral Size ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Non Volatile Memory ◽

Ferroelectric Capacitors ◽

Scanning Electron

Self-patterning presents an appealing alternative to lithography for the production of arrays of nanoscale ferroelectric capacitors for use in high density non-volatile memory devices. Recently a self-patterning method, based on the use of the instability of ultrathin films during hightemperature treatments, was used to fabricate nanosized ferroelectrics. This paper reports the use of the method for the preparation of PZT nanoislands on different single crystalline substrates - SrTiO3, MgO and LaAlO3. Moreover, a multi-step deposition procedure in order to control lateral the dimension of the crystals was introduced. The nanostructures obtained were studied by atomic force microscopy, scanning electron microscopy and X-ray diffraction.

Download Full-text