Enhanced pyroelectric properties of porous Ba0.67Sr0.33TiO3 ceramics fabricated with carbon nanotubes

Pyroelectric performance of porous Ba0.85Sr0.15TiO3 ceramics

“…22,23 Since the heat capacity of pores is much lower than that of BST ceramic, the heat capacity c v of porous ceramics is lower than that of dense ones. c v is determined by the eq.1 as shown 11 :…”

“…In this context, as their replacement, these three well‐known ferroelectrics based on BaTiO 3 , KNbO 3 , and Na 1/2 Bi 1/2 TiO 3 in pure and modified forms have been explored with renewed interest in the last decade. In this direction, few lead‐free porous ceramics based on modified BaTiO 3 (BT) have been recently reported such as Ba 0.5 Sr 0.5 TiO 3 and Ba 0.67 Sr 0.33 TiO 3 for their excellent pyroelectric properties, figure of merits (FOMs), and superior device performance . Moreover, air inclusions in the materials can help in reducing the effective acoustical impedance, thereby improving the acoustic matching between the component and the media through which signals could be transmitted/received which could improve the mismatch of acoustic impedances at the interfaces of medical ultrasonic imaging devices or underwater sonar detectors .…”

“…8,9 The composites seem to be another solution to tune all physical properties as per requirements. In this direction, porous ceramics have generated scientific interest since they can be promising materials for pyroelectric device applications where density and dielectric constant decrease drastically due to the incorporation of pores which are of scientific interest for many pyroelectric applications [10][11][12] . Significant amount of efforts have been put in by many academic groups/researchers to look for innovative processing technologies of porous ceramics, which ultimately can result in better control of the porous structures and substantial enhancements of the properties.…”

“…In this direction, few lead-free porous ceramics based on modified BaTiO 3 (BT) have been recently reported such as Ba 0.5 Sr 0.5 TiO 3 and Ba 0.67 Sr 0.33 TiO 3 for their excellent pyroelectric properties, figure of merits (FOMs), and superior device performance. 7,11,12 Moreover, air inclusions in the materials can help in reducing the effective acoustical impedance, thereby improving the acoustic matching between the component and the media through which signals could be transmitted/received which could improve the mismatch of acoustic impedances at the interfaces of medical ultrasonic imaging devices or underwater sonar detectors. 19 The Ba x Sr 1-x TiO 3 ceramics have been documented in literature for excellent pyroelectric and piezoelectric properties.…”

Intrinsic pyroelectric properties of thick, coarse grained Ba 1−x Sr x TiO 3 ceramics

“…Among pyroelectric materials, barium strontium titanate (Ba 1-x Sr x TiO 3 , BST) is intensively studied for several reasons: Sr is an effective solute for decreasing the paraelectricferroelectric phase transition temperature in a wide temperature range [12][13][14][15], leading to enhanced pyroelectric properties around room temperature; BST compositions are environmentally-friendly materials, which might represent viable alternatives to replace Pbbased oxides; the total pyroelectric coefficient can be very large in materials like BST, as shown in previous literature, especially due to the contribution of the induced part [16][17][18][19][20][21].…”