Sol–Gel Processing and Characterizations of a Ba_0.75Sr_0.25Ti _0.95Zr_0.05O₃ Ceramic

Abstract

A Ba0.75Sr0.25Ti0.95Zr0.05O3 ceramic was developed for use in nonlinear transmission line (NLTL) applications. The sol–gel process was used to synthesize Ba0.75Sr0.25Ti0.95Zr0.05O3 nanoparticles to achieve a uniform composition and a high surface area. Simultaneous thermal gravimetric analysis and differential thermal analysis (TGA/DTA) was used to identify the decomposition sequence as a function of temperature for the as‐synthesized powders. The phase transformation was confirmed by X‐ray diffraction (XRD). The calcined nanoparticles were hot‐pressed at 1300°C to achieve a high density. Microstructures were characterized using scanning electron microscopy (SEM). Several dielectric properties were measured and are reported.

Complex perovskite oxide nanocrystals: low-temperature synthesis and crystal structure

“…The synthesis of alkaline-earth perovskite oxide micro-and nanocrystals has been accomplished using a variety of methods that includes: solid state reaction, [6][7][8][9] molten salt, 10,11 sol-gel, 12,13 single-step combustion, 14,15 flame-spray pyrolysis, 16 thermal decomposition of a single-source precursor, 17 sol-precipitation, [18][19][20] reverse micelles, 21 polymeric precursor, 9 and solvothermal synthesis. [22][23][24][25][26][27] These synthetic approaches invariably rely on physical (heat, pressure) and/or chemical (salt, complexing agent, surfactant, mineralizer) agents to achieve a crystalline and phase-pure perovskite product.…”

Low Temperature Synthesis of Complex Ba1–xSrxTi1–yZryO3 Perovskite Nanocrystals

“…Although several synthetic strategies for the preparation of perovskite nanocrystals of formula Ba 1– x Sr x TiO 3 , and BaTi 1– y Zr y O 3 , have been developed, very few reports exist describing the synthesis of Ba 1– x Sr x Ti 1– y Zr y O 3 nanocrystals. In such cases, four-cation perovskite phases are typically synthesized via solid state reaction, , sol–gel, , and combustion synthesis . These approaches require thermal treatment at temperatures above 700 °C to produce a crystalline and phase pure product; this results in micrometer-sized grains with a broad size distribution.…”

“…Recently, there has been increased interest in developing synthetic approaches for the preparation of four-cation Ba 1−x Sr x Ti 1−y Zr y O 3 nanocrystals because of their potential as functional materials in tunable nonlinear transmission lines employed in telecommunications. 5 Although several synthetic strategies for the preparation of perovskite nanocrystals of formula Ba 1−x Sr x TiO 3 6,7 and BaTi 1−y Zr y O 3 8,9 have been developed, very few reports exist describing the synthesis of Ba 1−x Sr x Ti 1−y Zr y O 3 nanocrystals. In such cases, four-cation perovskite phases are typically synthesized via solid state reaction, 10,11 sol−gel, 5,12 and combustion synthesis.…”

A new sintering approach to ceramics at low temperature from Ba(ZrxTi1-x)O3 nanoparticles doped by ZnO

“…To further simplify the process and lower the processing temperature and pressure, several routs have been achieved [4][5][6][7][8][9][10][11][12]. Even more, perovskite structured nanocrystals with much complicated compositions have been developed based on above research works to develop new functional ceramics [13][14][15][16][17]. However, the agglomerations are inevitable in fine grain sized powders, especially in the nanoparticles, and thus the pores are hard to eliminate thoroughly during sintering.…”