Porous PZT Ceramics with Aligned Pore Channels for Energy Harvesting Applications

Abstract

In this study, aligned porous lead zirconate titanate (PZT) ceramics with high pyroelectric figures-of-merit were successfully manufactured by freeze casting using water-based suspensions. The introduction of aligned pores was demonstrated to have a strong influence on the resultant porous ceramics, in terms of mechanical, dielectric, and pyroelectric properties. As the level of porosity was increased, the relative permittivity decreased, whereas the Curie temperature and dielectric loss increased. The aligned porous structure exhibited improvement in the compressive strength ranging from 19 to 35 MPa, leading to easier handling, better processability and wider applications for such type of porous material. Both types of pyroelectric harvesting figures-of-merit (F E and F 0 E ) of the PZT ceramics with a porosity level of 25-45 vol% increased in all porous ceramics, for example, from 11.41 to 12.43 pJ/m 3 / K 2 and 1.94 to 6.57 pm 3 /J, respectively, at 25°C, which were shown to be higher than the dense PZT counterpart.

Biomolecular Piezoelectric Materials: From Amino Acids to Living Tissues

“…In addition, it has been reported that certain biological piezoelectric materials exhibit strong piezoelectricity that is comparable to that of conventional piezoelectric materials ( Table 1 ). Another main advantage of using biological piezoelectric materials for piezoelectric applications is their relatively low dielectric constant compared to the conventional piezoelectric materials because the piezoelectric voltage constant ( g ij ) is inversely proportional to the dielectric constant according to the following equation168–170 where d is the piezoelectric strain constant, g is the piezoelectric voltage constant, and ε is the dielectric constant. Although the discovered bio‐piezoelectric materials exhibit strong piezoelectric property, research on the piezoelectric properties of biomolecules still require further studies that accurately analyze the piezoelectric mechanism.…”

Structural phase transition and electrical properties of Sr2+ substituted porous PMN‐PZT ceramics

“…As can be seen from the transverse section of the specimen, there was a uniform pore size distribution with an average pore diameter of 130 μm and a thin pore wall of approximately 40 μm, smaller than that of samples produced utilizing CaCl 2 as the gelling agent, which was deduced to be caused by the decreasing rate constants of exchange with sodium alginate for the ascending ionic radii and atomic mass of Sr 2+ ion . As shown in Figure (B), the unidirectional pore channels along the diffusion direction of strontium cations extended to several millimeters with no obvious distortion or defects, which is more ideal than those prepared by many other methods in previous reports . Besides that, the detailed grain interconnectivity of pore walls in Figure (C) demonstrated that PMN‐PZT particles were joined together tightly with a smaller quantity of void space compared with our previous investigation …”

Diesel Exhaust Emission Soot Coated Pyroelectric Materials for Improved Thermal Energy Harvesting

“…This technique seems to have better efficiency than the known other sister techniques such as thermoelectric energy harvesting. Various concepts have been demonstrated for pyroelectric energy harvesting . Although results are promising, still these materials are only sufficient for low power electronic devices.…”