The influence of Pt and SrTiO3 interlayers on the microstructure of PbTiO3 thin films deposited by laser ablation on (001) MgO

1995 ◽  
Vol 10 (4) ◽  
pp. 791-794 ◽  
Author(s):  
S. Stemmer ◽  
S.K. Streiffer ◽  
W-Y. Hsu ◽  
F. Ernst ◽  
R. Raj ◽  
...  

We have used conventional and high-resolution transmission electron microscopy to investigate the microstruture of epitaxial, ferroelectric PbTiO3 films grown by pulsed laser ablation on (001) MgO single crystals, and on MgO covered with epitaxial Pt or SrTiO3. Pronounced variations are found in the widths and lengths of a-axis-oriented domains in these films, although the volume fraction of a-axis-oriented material varies only weakly for the different types of samples. In addition, the films deposited onto Pt-coated MgO have a larger grain size than those deposited onto bare MgO or SrTiO3/MgO. Possible reasons for the variations in the distribution of a-axis-oriented material in these samples include differences in the elastic properties and electrical conductivities of the different substrate combinations.

2004 ◽  
Vol 19 (4) ◽  
pp. 1118-1125 ◽  
Author(s):  
S. Bysakh ◽  
K. Mitsuishi ◽  
M. Song ◽  
K. Furuya ◽  
K. Chattopadhyay

Thin films with a nominal composition close to Ti62.5Si37.5 were deposited on NaCl substrate at room temperature by pulsed laser ablation to study the evolution of the intermetallic compound Ti5Si3 using a combination of high-resolution and in situ transmission electron microscopy. The as-deposited amorphous films contain Ti-rich clusters, which influence the phase evolution and the decomposition behavior of the amorphous film. These clusters influence the nucleation of a metastable fcc Ti solid solution (ao = 0.433 nm) with composition richer in Ti than Ti62.5Si37.5 as the first phase to crystallize at 773 K. The Ti5Si3 nanocrystals form later, and even at 1073 K they coexist with fine fcc Ti-rich nanocrystals. Subsequent Ar+ ion-milling of the crystallized film results in a loss of silicon. The composition change leads to the dissolution of the Ti5Si3 nanocrystals and evolution of a new metastable Ti-rich fcc phase (ao= 0.408 nm).


Author(s):  
Pankaj Koinkar ◽  
Kohei Sasaki ◽  
Tetsuro Katayama ◽  
Akihiro Furube ◽  
Satoshi Sugano

Two dimensional (2D) materials are widely attracting the interest of researchers due to their unique crystal structure and diverse properties. In the present work, tungsten disulfide (WS[Formula: see text] nanorods were synthesized by a simple method of pulsed laser ablation in liquid (PLAL) environment. The prepared WS2 are analyzed by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV-visible spectroscopy (UV-vis) and Raman spectroscopy to confirm the surface morphology, phase and structure. A possible growth mechanism of WS2 is proposed. This study indicates new door for the preparation of 2D materials with specific morphology.


2011 ◽  
Vol 415-417 ◽  
pp. 747-750
Author(s):  
Bing Xu ◽  
Ren Guo Song ◽  
Chao Wang

In order to study the effects of laser fluence on silver nanoparticles colloid, the silver nanoparticles colloid was prepared by pulsed laser ablation of silver target for 10min in distilled water at different laser fluence. The particles size,morphologies and absorption spectroscopy of the obtained nanoparticles colloid were characterized by ultraviolet to visible (UV-Vis) spectrometer and transmission electron microscopy (TEM), the average diameter and its distribution were analyzed by Image-ProPlus software. The results shown that the average diameter of the silver nanoparticles prepared at the laser fluence of 4.2J/cm2 was the smallest (D=17.54nm), also, the distribution of particle size was narrowest (=36.86nm) and the morphologies were more homogeneous. It was confirmed that the nanoparticles size and shape could be controlled by pulsed laser ablation parameters.


2012 ◽  
Vol 538-541 ◽  
pp. 1888-1891 ◽  
Author(s):  
Bing Xu ◽  
Ren Guo Song ◽  
Chao Wang ◽  
Wang Zhao He

The silver nanoparticles colloid was prepared by pulsed laser ablation in distilled water under various laser repetition rates. The particles size, morphologies and absorption spectroscopy of the obtained nanoparticles colloids were characterized by ultraviolet to visible (UV-Vis) spectrometer and transmission electron microscopy (TEM). The average diameter and its distribution were analyzed by Image-ProPlus software. The results showed that the average diameter of the silver nanoparticles prepared at the laser repetition rate of 10 HZ was the smallest (D=29.75 nm), also, the distribution of particle size decreases with increasing the laser repetition rate.


1998 ◽  
Vol 526 ◽  
Author(s):  
R. Kalyanaraman ◽  
S. Oktyabrsky ◽  
K. Jagannadham ◽  
J. Narayan

AbstractThe atomic structure of grain boundaries in pulsed laser deposited YBCO/MgO thin films have been studied using transmission electron microscopy. The films have perfect texturing with YBCO(001)//MgO(001), giving rise to low-angle [001] tilt boundaries from the grains with the c-axis normal to substrate surface. Low angle grain boundaries have been found to be aligned preferentially along (100) and (110) interface planes. The energy of (110) boundary planes described by an alternating array of [100] and [010] dislocation is found to be comparable to the energy of a (100) boundary. The existence of these split dislocations is shown to further reduce the theoretical current densities of these boundaries indicating that (110) boundaries carry less current as compared to (100) boundaries of the same misorientation angle. Further, Z-contrast transmission electron microscopy of a 42° asymmetric high-angle grain boundary of YBCO shows evidence for the existence of boundary fragments and a reduced atomic density along the boundary plane


2018 ◽  
Vol 243 ◽  
pp. 00017 ◽  
Author(s):  
Daria Goncharova ◽  
Ekaterina Gavrilenko ◽  
Anna Nemoykina ◽  
Valery Svetlichnyi

The paper studies physicochemical and antibacterial properties of ZnO nanoparticles obtained by pulsed laser ablation in water and air. Their composition and structure were studied by X-ray diffraction, transmission and scanning electron microscopy. Antibacterial activity of the nanoparticles was examined by its affection on Gram-positive Staphylococcus aureus (S.aureus). The dependence of nanoparticles’ physical and chemical antibacterial properties on the conditions of the ablation was shown. The model materials for the antibacterial bandage were made of cotton, filter paper and biodegradable polymer scaffolds (poly-l-lactide acid), and then they were coated with the obtained ZnO nanoparticles. The model bandage materials were examined by the scanning electron microscopy method and their antibacterial activity (ISO 20743:2013) was determined. High activity of all the samples against S.aureus was proved.


2000 ◽  
Vol 623 ◽  
Author(s):  
N.D. Zakharov ◽  
A.R. James ◽  
A. Pignolet ◽  
S. Senz ◽  
D. Hesse

AbstractEpitaxial, ferroelectric Ba2Bi4Ti5O18 films grown on LaNiO3/CeO2/ZrO2:Y2O3 epitaxial layers on Si(100) are investigated by cross-section high-resolution transmission electron microscopy (HRTEM). The films are perfectly oriented and consist of well-developed grains of rectangular shape. The grain boundaries are strained and contain many defects, especially a new type of defect, which can be described as a staircase formed by repeated lattice shifts of Δ ∼ c/12 ∼ 4.2 Å in the [001] direction. This repeated shift results in seemingly bent ribbons of stacked Bi2O2 planes, involving, however, individual Bi2O2 planes which remain strongly parallel to the (001) plane. These defects contain an excess of bismuth. Other defects found in the grain interior include mistakes in the stacking sequence originating from the presence of single, well-oriented, non-stoichionietric layers intergrown with the stoichiometric Ba2Bi4Ti5O18 film matrix.


2011 ◽  
Vol 412 ◽  
pp. 263-266
Author(s):  
Hong Wei Zhang ◽  
Li Li Zhang ◽  
Feng Rui Zhai ◽  
Jia Jin Tian ◽  
Can Bang Zhang

The higher mechanical strength of Al87Ce3Ni8.5Mn1.5 nanophase amorphous composites has been obtained with two methods. The first nanophase amorphous composites are directly produced by the single roller spin quenching technology. The method taken for the second nanophase amorphous composites is at first to obtain amorphous single-phase alloy, followed by annealed at different temperatures .The formative condition, the microstructure, the particle size, the volume fraction of α-Al phase and microhardness of nanophase amorphous composites etc have been investigated and compared by X-ray diffraction (XRD) and transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The microstructure of composites produced by the second method is higher than the former, the fabricated material structure of the system is more uniform and the process is easier to control.


Sign in / Sign up

Export Citation Format

Share Document