Structure and electrorheological properties of nanoporous BaTiO3 crystalline powders prepared by sol–gel method

• Published in: Journal of sol-gel science and technology Vol. 52; no. 1; pp. 8 - 14
• Main Authors: Jiang, Wanquan, Jiang, Chuanxia, Gong, Xinglong, Zhang, Zhong
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01.10.2009; Springer; Springer Nature B.V
• Subjects: Barium titanates; Ceramics; Chemical composition; Chemistry; Chemistry and Materials Science; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Composites; Crystal structure; Crystallinity; Crystallites; Electric fields; Ethylene oxide; Exact sciences and technology; General and physical chemistry; Glass; Gravimetric analysis; Inorganic Chemistry; Low currents; Materials Science; Microscopy; Morphology; Nanotechnology; Natural Materials; Optical and Electronic Materials; Organic chemistry; Porous materials; Propylene oxide; Review; Rheological properties; Rheology; Roasting; Scanning electron microscopy; Sol-gel processes; Specific surface; Surface area; Surface physical chemistry; Transmission electron microscopy; X-ray diffraction; Yield stress; BaTiO; Sol–gel; Electrorheological properties; Porous; Ternary compound; Gravimetric analysis; Barium; Barium titanates; Porous material; Powder; Template; Ethylene oxide polymer; Crystallites; Pore size; Chemical composition; Silicon; Structure; Nanoporosity; Scanning electron microscopy; Sol-gel; Transition element compounds; Chemical structure; Thermogravimetry; Desorption; Nitrogen; X ray diffraction; Oil; Transmission electron microscopy; Adsorption; Pore; Sol gel process; Morphology; Oxirane(methyl); Electrorheological fluid; Surface area; Rheological properties
• DOI: 10.1007/s10971-009-2011-5
• ISSN: 0928-0707

In this paper, a novel nanoporous barium titanate (BaTiO 3 ) crystalline powder was synthesized by using triblock poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) based systems (P-123) as the soft template via a sol–gel method and their structure-dependent electro rheological property was studied. The pore diameter and specific surface area of BaTiO 3 were precisely controlled by varing the calcined temperature. The chemical composition, structure and surface morphology of BaTiO 3 were characterized by X-ray diffraction (XRD), thermo gravimetric analysis (TGA), and nitrogen adsorption–desorption method, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The result revealed that the pore volume and specific surface area of BaTiO 3 decreased with the increment of calcined temperature. The electro rheological fluids (ERFs) were obtained by dispersing BaTiO 3 crystallites in silicon oil and three kinds ERFs were fabricated by using three kinds of BaTiO 3 which were prepared under different calcined temperature (550, 600 and 900 °C) as the precursors. The behaviors of the ERFs were evaluated via a rotational rheometer fixed with electric field generator. The results showed that electro rheological effect was related to the pore volume and specific surface area of BaTiO 3 . Due to the distinct advantage of sol–gel method for preparing nanoporous BaTiO 3 without contamination of the materials, the markedly low current destiny of the ERFs was obtained. The yield stress of ERFs with large specific surface area of BaTiO 3 reached the maximum of 3 kPa, which is higher than that of ERFs using traditional pure BaTiO 3 crystallites (lower than 1 kPa).