Characterization of cerate–zirconate ceramic powder prepared by a high-pressure–high-temperature batch-wise reactor system

Abstract

A supercritical technique was proposed to synthesise cerate-zirconate ceramic compound by a highpressure-high-temperature batch-wise reactor system. TG thermogram of the dried powders for all samples showed three stages of weight loss. Each stage is corroborated by one or two exothermic peaks as shown in DTG signal. A complete thermal decomposition for all samples is accomplished at *977°C for 2 h. FT-IR and XRD patterns showed the traces of carbonate residue in the calcined samples is due to the incomplete combustion of intermediate compounds. The presence of secondary phases, namely, BaZrO 3 , BaCeO 3 , BaO 2 and CeO 2 as detected by XRD measurement indicates that the calcined samples are not in a single phase of cerate-zirconate compound.

Influence of Triple Sintering Additives (BaO-CuO-B2O3) on the Sintering Behavior and Conductivity of the Proton-Conducting BaZr0.1Ce0.7Y0.2O3−δ Electrolyte Sintered at 1150 °C

“…Figure c shows the FT-IR spectra of BZCY-3 sintered at 1100, 1150, and 1200 °C. The IR spectra show a stretching vibration at 857 and 1400 cm –1 which is attributed to the presence of the CO 3 2– functional group. , This indicates the presence of a small amount of BaCO 3 . Citric acid was used in the preparation of electrolyte powder; the carboxylic group of citric acid may be contributed to the formation of BaCO 3.…”

“…The lattice contraction is attributed to the replacement of larger size Ce 4+ with smaller size Cu 2+ at the B-site. 37 The ionic radius of B 3+ (0.23 Å) and Cu 2+ (0.73 Å) is smaller than the ionic radius of B-sited Ce 4+ . Cu 2+ having an ionic radius close to Ce 4+ (0.87 Å) occupied the B-site, resulting in improved sintering behavior and conductivity of BZCY by forming oxygen vacancies.…”

“…The TGA/DSC curve of BZCY-3 in Figure 2a 35 The formation of the second phase of Ba 2 YCu 3 O x before the BaO-CuO eutectic liquid phase is the reason for the delayed sintering that occurs in BZCY. 37 Ba 2 YCu 3 O x decomposes at 1030 °C and accelerates densification. The weight loss of the sample occurs at 750− 1000 °C because of the B 2 O 3 volatilization that occurs under high-temperature sintering.…”

“…This difference in conductivity is due to the role played by different sintering additives in the BZCY electrolyte. Sintering additives like ZnO reduce the sintering temperature but accumulate at the grain boundaries, 37 resulting in lower conductivity. As shown in Figure 6d, metal oxides NiO, CuO, and ZnO have limited ability to enhance the sintering activity of proton conductors, and composite sintering aids produce lower melting point compounds during the sintering process.…”

Binding Sites of Deprotonated Citric Acid and Ethylenediaminetetraacetic Acid in the Chelation with Ba2+, Y3+, and Zr4+ and Their Electronic Properties: a Density Functional Theory Study

“…Currently, perovskite is one of the most studied compounds in the field of materials science. [1][2][3] Ceramic perovskite-type oxides, with a general formula ABO 3 where A and B are two metal cations of different sizes, have been studied due to their high conductivity and low activation energy. 4,5 Cerate zirconate attracts much attention among perovskite-type oxides because it is important for the future development of electrochemical devices such as fuel cells, magnetic refrigeration, and solar cells.…”