scholarly journals Dipole Relaxation in Semiconducting Zn2−xMgxInV3O11 Materials (Where x = 0.0, 0.4, 1.0, 1.6, and 2.0)

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2425
Author(s):  
Tadeusz Groń ◽  
Monika Bosacka ◽  
Elżbieta Filipek ◽  
Sebastian Pawlus ◽  
Andrzej Nowok ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Reaction Method ◽  
State Density ◽  
Dipole Relaxation ◽  
Broadband Dielectric Spectroscopy ◽  
Semiconducting Properties ◽  
The Matrix ◽  
Spectroscopy Studies ◽  
Mg Content ◽  
Mg Doped

This paper reports on the electrical and broadband dielectric spectroscopy studies of Zn2−xMgxInV3O11 materials (where x = 0.0, 0.4, 1.0, 1.6, 2.0) synthesized using a solid-state reaction method. These studies showed n-type semiconducting properties with activation energies of 0.147–0.52 eV in the temperature range of 250–400 K, symmetric and linear I–V characteristics, both at 300 and 400 K, with a stronger carrier emission for the matrix and much less for the remaining samples, as well as the dipole relaxation, which was the slowest for the sample with x = 0.0 (matrix) and was faster for Mg-doped samples with x > 0.0. The faster the dipole relaxation, the greater the accumulation of electric charge. These effects were analyzed within a framework of the DC conductivity and the Cole–Cole fit function, including the solid-state density and porosity of the sample. The resistivity vs. temperature dependence was well fitted using the parallel resistor model. Our ab initio calculations also show that the bandgap increased with the Mg content.

Terahertz Spectroscopy Studies of Solid-State Salicylic Acid

2015 ◽  
Vol 1117 ◽  
pp. 65-68
Author(s):  
Kateryna Zelenska ◽  
Hiroko Kimura ◽  
Tetsuo Sasaki ◽  
Toru Aoki ◽  
Volodymyr Gnatyuk
Keyword(s):  
Salicylic Acid ◽  
Solid State ◽  
Density Functional ◽  
Organic Molecules ◽  
Terahertz Spectroscopy ◽  
Experimental Studies ◽  
State Density ◽  
Functional Theory ◽  
Absorbance Spectroscopy ◽  
Spectroscopy Studies

Molecular and lattice vibration frequencies of solid-state salicylic acid were studied in the Terahertz (THz) and Mid-Infrared (Mid-IR) ranges. The calculation of the THz and Mid-IR spectra of salicylic acid which was based on the solid-state density functional theory (DFT) was carried out. Experimental studies were conducted by THz absorbance spectroscopy and Fourier transform infrared spectroscopy (FTIR) methods. Vibrations revealed in “finger-print” spectrum of salicylic acid were compared with the typical vibrations of groups of atoms that make up organic molecules.

Fabrication and Properties of Zinc Silicate Phosphors through Solid State Reaction

2010 ◽  
Vol 160-162 ◽  
pp. 594-598
Author(s):  
Guo Jian Jiang ◽  
Jia Yue Xu ◽  
Hui Shen ◽  
Yan Zhang ◽  
Lin He Xu ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Solid State Reaction Method ◽  
Emission Peak ◽  
Zinc Silicate ◽  
Red Phosphor ◽  
Reaction Method ◽  
Long Afterglow ◽  
Luminescent Mechanism ◽  
Silicate Phosphors

Zinc silicate-based (Zn2SiO4:Eu3+) long afterglow phosphors were produced by solid state reaction method. The effects of borax and Eu2O3 additive on the properties of fabricated products have been studied. The results show that, there is not much difference in phase compositions within the borax additive amount; however, their SEM morphologies are different. Borax additive can increase the grain size of the product. Some sintering phenomena could be observed in the sample with Eu2O3 addition. The fluorescence spectroscopy results indicate that, the emission peak of the sample with Eu3+ additive located at 612nm, which may be a good candidate for red phosphor applications. The luminescent mechanism of Zn2SiO4:Eu3+ is also discussed.

scholarly journals DC and AC Conductivity, Biosolubility and Thermal Properties of Mg-Doped Na2O–CaO–P2O5 Glasses

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2626
Author(s):  
Natalia Anna Wójcik ◽  
Sharafat Ali ◽  
Jakub Lech Karczewski ◽  
Bo Jonson ◽  
Michał Bartmański ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Saline Solution ◽  
Glass Structure ◽  
Glass Network ◽  
Bioactive Glasses ◽  
Dc And Ac Conductivity ◽  
Impedance Spectroscopy Technique ◽  
Mg Content ◽  
Phosphate Buffered Saline ◽  
Mg Doped

Bioactive glasses have recently been extensively used to replace, regenerate, and repair hard tissues in the human body because of their ability to bond with living tissue. In this work, the effects of replacing Na2O with MgO on the electrical, biosolubility, and thermal properties of the target glass 10Na2O–60P2O5–30CaO (in mol%) were investigated. The electrical properties of the glasses were studied with the impedance spectroscopy technique. At 473 K, DC conductivity values decreased from 4.21 × 10−11 to 4.21 × 10−12 S cm−1 after complete substitution of MgO for Na2O. All samples had a similar activation energy of the DC conduction process ~1.27 eV. Conduction mechanisms were found to be due to hop of ions: Na+, Mg2+, and probable H+. FTIR analysis showed that, as the Mg content increased, the Q2 unit (PO2−) shifted towards higher wavenumbers. The proportion of Q3 unit (P2O5) decreased in the glass structure. This confirmed that the replacement of Na+ by Mg2+ was accompanied by concurrent polymerization of the calcium–phosphate glass network. The biosolubility test in the phosphate-buffered saline solution showed that the magnesium addition enhanced the biosolubility properties of Na2O–CaO–P2O5 glasses by increasing their dissolution rate and supporting forming CaP-rich layers on the surface. The glass transition temperature increased, and thermal stability decreased substantially upon substitution of Na2O by MgO.

scholarly journals Growth of single crystals in the (Na1/2Bi1/2)TiO3–(Sr1–xCax)TiO3 system by solid state crystal growth

2021 ◽  
Author(s):  
Phan Gia Le ◽  
Huyen Tran Tran ◽  
Jong-Sook Lee ◽  
John G. Fisher ◽  
Hwang-Pill Kim ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Solid State ◽  
Single Crystal ◽  
Single Crystals ◽  
Piezoelectric Properties ◽  
Single Crystal Growth ◽  
Crystal Growth Rate ◽  
Large Strains ◽  
Growth Technique ◽  
The Matrix

AbstractCeramics based on (Na1/2B1/2)TiO3 are promising candidates for actuator applications because of large strains generated by an electric field-induced phase transition. For example, the (1−x)(Na1/2Bi1/2)TiO3-xSrTiO3 system exhibits a morphotropic phase boundary at x = 0.2–0.3, leading to high values of inverse piezoelectric constant d*33, which can be further improved by the use of single crystals. In our previous work, single crystals of (Na1/2B1/2)TiO3-SrTiO3 and (Na1/2B1/2)TiO3-CaTiO3 were grown by the solid state crystal growth technique. Growth in the (Na1/2B1/2)TiO3-SrTiO3 system was sluggish whereas the (Na1/2B1/2)TiO3-CaTiO3 single crystals grew well. In the present work, 0.8(Na1/2Bi1/2)TiO3-0.2(Sr1−xCax)TiO3 single crystals (with x = 0.0, 0.1, 0.2, 0.3, 0.4) were produced by the solid state crystal growth technique in an attempt to improve crystal growth rate. The dependence of mean matrix grain size, single crystal growth distance, and electrical properties on the Ca concentration was investigated in detail. These investigations indicated that at x = 0.3 the matrix grain growth was suppressed and the driving force for single crystal growth was enhanced. Replacing Sr with Ca increased the shoulder temperature Ts and temperature of maximum relative permittivity Tmax, causing a decrease in inverse piezoelectric properties and a change from normal to incipient ferroelectric behavior.

Luminescence properties of dysprosium doped calcium magnesium silicate phosphor by solid state reaction method

2015 ◽  
Vol 649 ◽  
pp. 1329-1338 ◽  
Author(s):  
Ishwar Prasad Sahu ◽  
Priya Chandrakar ◽  
R.N. Baghel ◽  
D.P. Bisen ◽  
Nameeta Brahme ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Magnesium Silicate ◽  
Solid State Reaction Method ◽  
Luminescence Properties ◽  
Reaction Method ◽  
Silicate Phosphor ◽  
Calcium Magnesium
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