Structural, Electrical and FT-IR Studies of Nano Zn1-xCaxO by Solid State Reaction Method

2014 ◽  
Vol 938 ◽  
pp. 63-70 ◽  
Author(s):  
Tanushree Das ◽  
Bikram Keshari Das ◽  
Kajal Parashar ◽  
S.K.S. Parashar ◽  
Rao Alluri Nagamalleswara

Single phase polycrystalline with = 0, 0.01 and 0.02 were synthesized by conventional solid state reaction method. The X-ray diffraction shows that the ceramic samples has hexagonal Wurtzite structure with a space group of p63mc and average crystallite size in the range 52 - 88 nm. The dielectric and electrical properties were studied within the temperature range 30 °C to 500 °C under air atmosphere as function of frequency (10 kHz). The electrical properties of grain interior and grain boundary have been studied by using the impedance spectroscopy and follow the non-Debye relaxation process. It was observed that the AC conductivity of ceramic samples following the Universal power law within the frequency range 1kHz to 1 MHz. The activation energy of Pure is 0.29 eV was calculated by using the Arrhenius-relation with in temperature range 300 - 500 °C, which is increased to (0.40 eV ) when = 0.02 of at 10 kHz . The peaks attributed at 1415 cm-1 () and 1413 cm-1 () in FT-IR measurement of are due to Ca-O stretching from the calcite phase of CaCO3, which is not observed in Pure ZnO confirms the presence of Ca in ZnO lattice. Keywords: , FT-IR, Impedance spectroscopy, ac conductivity, Dielectric constant.

2018 ◽  
Vol 70 (3) ◽  
pp. 560-567 ◽  
Author(s):  
Jian Feng Li ◽  
Qin Shi ◽  
HeJun Zhu ◽  
ChenYu Huang ◽  
Shuai Zhang ◽  
...  

Purpose This paper aims to clarify the size and morphology of transition metal dichalcogenides has an impact on lubrication performance of Cu-based composites. This study is intended to show that Cu-based electrical contact materials containing Nb0.91Ti0.09Se2 have better electrical and tribological properties than those containing NbSe2. The tribological properties of Cu-based with different Ti-dopped NbSe2 content were also discussed. Design/methodology/approach The NbSe2 and Nb0.91Ti0.09Se2 particles were fabricated by thermal solid state reaction method. The powder metallurgy technique was used to fabricate composites with varying Nb0.91Ti0.09Se2 mass fraction. The phase composition of Cu-based composites was identified by X-ray diffraction, and the morphology of NbSe2/Nb0.91Ti0.09Se2 and the worn surface of composites were characterized by scanning electron microscopy and transmission electron microscopy. In addition, the tribological properties of composites were appraised using a ball-on-disk multi-functional tribometer. The data of friction coefficient and resistivity were analyzed and the corresponding conclusion was drawn. Findings In comparison with the pure copper, Cu-based composites containing Nb0.91Ti0.09Se2/NbSe2 had a lower friction coefficient, illustrating the Nb0.91Ti0.09Se2 with nano-size particles prepared in this work is a perfect choice for the fabrication of excellent electrical contact composites. Compared to composites with NbSe2, composites containing Nb0.91Ti0.09Se2 have better tribological and electrical properties. Research limitations/implications Because of the use of thermal solid state reaction method, the size of NbSe2 and Nb0.91Ti0.09Se2 is relatively large. Therefore, the fabrication of finer particles of Nb0.91Ti0.09Se2 is encouraged. Originality/value In this paper, the authors discuss the tribological and electrical properties of Cu-based composites, and the value of optimum obtained as Nb0.91Ti0.09Se2 content is 15 Wt.%.


RSC Advances ◽  
2018 ◽  
Vol 8 (28) ◽  
pp. 15613-15620 ◽  
Author(s):  
Xiaochun He ◽  
Ruiqing Chu ◽  
Zhijun Xu ◽  
Zhongran Yao ◽  
Jigong Hao

Lead-free ceramics, SrBi2Nb2O9–xBi2O3 (SBN–xBi), with different Bi contents of which the molar ratio, n(Sr) : n(Bi) : n(Nb), is 1 : 2(1 + x/2) : 2 (x = −0.05, 0.0, 0.05, 0.10), were prepared by conventional solid-state reaction method.


2007 ◽  
Vol 336-338 ◽  
pp. 409-412
Author(s):  
Jun Feng ◽  
Jing Hua Gu ◽  
Yue Zhang ◽  
Wei Shen Yang

The solid-state reaction method and the liquid citrate method were used respectively to synthesize SrCe0.9Y0.1O3-α (SCY10) powders. SCY10 membranes were prepared from each kind of the powders by sintering at 1450°C for 10 hours. XRD was employed to examine the phase of the powders and the membranes. The microstructure of the membranes was observed with SEM. The sintering ability and electrical properties of the membranes were investigated. The results indicate that the membrane prepared from SCY10 powder synthesized by the liquid citrate method has higher relative density and nearly the same conductivity, compared with the membrane prepared from SCY10 powder synthesized by solid-state reaction.


RSC Advances ◽  
2016 ◽  
Vol 6 (40) ◽  
pp. 33387-33392 ◽  
Author(s):  
Zhongran Yao ◽  
Ruiqing Chu ◽  
Zhijun Xu ◽  
Jigong Hao ◽  
Guorong Li

Lead-free piezoelectric ceramics with the formula of Sr1−x(Li,Ce)x/2(Na0.5Bi0.5)Bi4Ti5O18 (LCSNBT-x, x = 0.0, 0.1, 0.2, 0.3, 0.4), were prepared by a conventional solid-state reaction method.


2008 ◽  
Vol 368-372 ◽  
pp. 129-131
Author(s):  
Yong He ◽  
Ke Pi Chen ◽  
Dong Yu Liu ◽  
Zong De Liu

CaCu3(Ti1-xZrx)O12 ceramics (x = 0.02, 0.04, 0.06, 0.08) were prepared by the conventional solid-state reaction method. Phase compositions, microstructure and dielectric properties were examined by XRD, SEM and impedance spectroscopy, respectively. The experimental results indicated that there is no obvious effect on microstructure characteristic by substituting Zr4+ for Ti4+. It was found that the values of the dielectric constant for all of the samples dropped into the order of 102, which is significantly lower than the order of 105 that of normally reported in the literature. It was suggested that the presence of impurity phases played an important role for the degeneracy of dielectric properties.


RSC Advances ◽  
2016 ◽  
Vol 6 (17) ◽  
pp. 13803-13808 ◽  
Author(s):  
Zhongran Yao ◽  
Ruiqing Chu ◽  
Zhijun Xu ◽  
Jigong Hao ◽  
Juan Du ◽  
...  

Bismuth layer-structured ferroelectrics with a formula of Sr1−x(K,Ce)x/2(Na0.5Bi0.5)Bi4Ti5O18, were prepared by a conventional solid-state reaction method.


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