New Potassium–Sodium Niobate Ceramics with a Giant d₃₃

Abstract

For potassium-sodium niobate, poor piezoelectric properties always perplex most researchers, and then it becomes important to attain a giant piezoelectricity. Here we reported a giant piezoelectric constant in (1-x)(K0.48Na0.52)(Nb0.95Sb0.05)O3-xBi0.5Ag0.5ZrO3 lead-free ceramics. The rhombohedral-tetragonal phase boundary was shown in the ceramics with 0.04<x≤0.05, and then the ceramic with x=0.0425 possesses a giant d33 of ∼490 pC/N. We also discussed the physical mechanisms of enhanced piezoelectricity. As a result, such a research can benefit the sustainable development of (K,Na)NbO3 materials.

Characteristics of giant piezoelectricity around the rhombohedral-tetragonal phase boundary in (K,Na)NbO3-based ceramics with different additives

“…10 To confirm this special relationship, the ε r P r values of KNNS-BNKZ ceramics with different additives were plotted, as shown in Fig. 7.…”

“…L. E. Cross thought that this result is a symbol of "lead-free at last" in the near future [8]. Recently, in our group, we reported some KNN -based material systems with a giant piezoelectricity (d 33~4 90 pC/N) using the new ideas of constructing R-T phase boundary [9][10]. As a result, it can be believed that the modifications of phase boundaries will become a powerful tool to promote piezoelectric properties in a material [11].…”

Structure and electrical properties of K0.5Na0.5Nb0.94−Sb0.06Sn O3 lead-free piezoelectric ceramics

“…Therefore, it is necessary to develop lead-free piezoelectric ceramics with excellent piezoelectric properties for replacing the lead-based ceramics in various devices. Alkali metal niobate-based ferroelectric ceramics have been paid much attention because of their excellent dielectric, piezoelectric and ferroelectric properties, and became one of the most promising candidates for replacing PZT-based ceramics [7][8][9][10][11].…”

High‐Performance Lead‐Free Piezoceramics with High Curie Temperatures

“…[1][2][3] Lead-free piezoelectric materials have been studied to replace the commonly used lead zirconate titanate (PZT) because of environmental and health issues. [ 2,[4][5][6][7] Piezoelectric properties are usually inversely proportional to the phase transition Curie temperature ( T C ), [5][6][7][8][9][10] but PZT is an exception that has good piezoelectric properties with a high T C . Here, we show that a bismuth ferrite (BF) and barium titanate (BT) solid solution system can achieve good piezoelectric properties with a high T C when fabricated with low-temperature sintering followed by a water-quenching process, with no complicated grain alignment processes performed.…”

“…[ 11 ] For sodium potassium niobate (NKN)-based ceramics, polymorphic phase transition (PPT) has been used for the same purpose. [7][8][9] Therefore, fabricating piezoceramics with chemical compositions around their MPB or PPT is an effective method for obtaining good piezoelectric properties. [7][8][9][10][11][12][13] For the NKN-based system, the best performance ( d 33 = 490 pC N −1 , T C = 227 °C) was exhibited in 0.96(Na 0.52 K 0.48 )-(Nb 0.95 Sb 0.05 )O 3 -0.04Bi 0.5 (Na 0.92 K 0.18 ) 0.5 ZrO 3 (NKNSb) ceramic.…”