High room-temperature pyroelectric property in lead-free BNT-BZT ferroelectric ceramics for thermal energy harvesting. Issue 5 (May 2019)

• Record Type: Journal Article
• Authors: Shen, Meng; Li, Wenru; Li, Ming-Yu; Liu, Huan; Xu, Jianmei; Qiu, Shiyong; Zhang, Guangzu; Lu, Zixiao; Li, Honglang; Jiang, Shenglin
• Is Part Of: Journal of the European Ceramic Society. Volume 39:Issue 5(2019)
• Page Start: 1810
• Page End: 1818
• Publication Date: 2019-05
• Subjects: BNT-BZT ceramics -- Phase transition -- Room temperature pyroelectric property -- Energy harvesting; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2019.01.012
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: Pyroelectrics are attracting increasing attention because they enable pyroelectric generators to extract energy from low-gradient-temperature heat for portable electronic devices. High pyroelectric coefficient around room temperature is essential for high-performance energy harvesters, which, unfortunately, is only commonly achieved in lead-based ferroelectrics. Herein we report a high room temperature pyroelectric response of 27.2 × 10 −4 C m -2 K -1 in 0.94(Bi0.5 Na0.5 )TiO3 -0.06Ba(Ti0.75 Zr0.25 )O3 lead-free ceramics by modulating the Zr 4+ /Ti 4+ ratio to tune the ferroelectric-relaxor antiferroelectric-like phase transition point to around ambient temperature, whose pyroelectric response is one order of magnitude higher than that of the sample without Zr and even comparable to those of lead-containing pyroelectrics. The theoretical analysis revealed that introduced Zr 4+ could incorporate into the TiO6 octahedral lattices and break the long-range translational symmetry of BaTiO3 lattices, resulting in the reduction of B-site ion displacement activation energy and transition point of ferroelectric-relaxor antiferroelectric-like phase, giving rise to a pronounced room-temperature pyroelectric effect in BNT-BZT.