Effects of silica coating on the microstructures and energy storage properties of BaTiO3 ceramics. (July 2015)

• Record Type: Journal Article
• Authors: Zhang, Yiming; Cao, Minghe; Yao, Zhonghua; Wang, Zhijian; Song, Zhe; Ullah, Atta; Hao, Hua; Liu, Hanxing
• Is Part Of: Materials research bulletin. Volume 67(2015:Jul.)
• Page Start: 70
• Page End: 76
• Publication Date: 2015-07
• Subjects: Ceramics -- Dielectric properties -- Electrical properties -- Energy storage; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2015.01.056
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: BaTiO3 cores remained up to the original grain size after sintering. The homogeneity of silica coating dominates contribution to breakdown strength. Energy storage density of BaTiO3 ceramics increases sharply by silica coating. Abstract: We investigated microstructures and energy storage properties of SiO2 -coated BaTiO3 ceramics that were prepared by the so-called Stöber process. The thickness of coating layer of BaTiO3 powders could be effectively controlled by the silica content. It could be observed that the secondary phases Ba2 TiSi2 O8 appeared in the coated BaTiO3 ceramics due to the interdiffusion reactions between SiO2 and BaTiO3 components under sintering. BaTiO3 cores in the coated ceramics remained up to the original grain size indicating the coating layer as an inhibitor. The results showed that both breakdown strength and energy density were improved apparently. The homogeneity of silica coating in the ceramics should dominate contribution to breakdown strength, which can reduce the weak-point breakdown under high electric field. The optimized composition for BaTiO3 ceramic coated with 2.0 wt% SiO2 showed the maximum energy storage density of 1.2 J/cm 3 with energy storage efficiency of 53.8%, which is about three times higher than that of pure BaTiO3 (0.37 J/cm 3 ).