Enhanced dielectric breakdown strength and energy storage density in lead-free relaxor ferroelectric ceramics prepared using transition liquid phase sintering. Issue 41 (7th April 2016)

• Record Type: Journal Article
• Authors: Qu, Bingyue; Du, Hongliang; Yang, Zetian; Liu, Qinghui; Liu, Tonghao
• Is Part Of: RSC advances. Volume 6:Issue 41(2016)
• Page Start: 34381
• Page End: 34389
• Publication Date: 2016-04-07
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra01919f
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Lead-free relaxor ferroelectric ceramics have been widely explored for high power energy storage applications because of their high polarization saturation and low remnant polarization. Abstract : Lead-free relaxor ferroelectric ceramics have been widely explored for high power energy storage applications because of their high polarization saturation and low remnant polarization. However, lead-free relaxor ceramics with the bulk form exhibit low recoverable energy storage density ( W rec < 2 J cm −3 ) owing to low dielectric breakdown strength (DBS <200 kV cm −1 ). Here we use a strategy (the transition liquid phase sintering) to decrease the porosity and increase DBS of lead-free relaxor ferroelectric ceramics. This is achieved by introducing ZnO into 0.8(K0.5 Na0.5 )NbO3 –0.2Sr(Sc0.5 Nb0.5 )O3 (0.8KNN–0.2SSN) ceramics. A dense microstructure (a low porosity) and submicron sized grains were found for 0.8KNN–0.2SSN– x mol%ZnO ceramics, which is responsible for a large DBS (400 kV cm −1 ). Both a large W rec (2.6 J cm −3 ) and high energy storage efficiency (73.2%) were achieved for 0.8KNN–0.2SSN–0.5 mol%ZnO ceramics. The W rec of 2.6 J cm −3 exceeds all the other reported results of lead-free bulk ceramics. The 0.8KNN–0.2SSN–0.5%ZnO ceramics are believed to be an attractive material for high power energy storage applications.