Energy conversion with Zr-rich lead zirconate/titanate ceramics

The conversion efficiency and power output to convert thermal energy to electrical energy by means of a ferroelectric–ferroelectric phase transition has been investigated. The material used was the ceramic mixed system lead zirconate/titanate (PZT) with a very Zr-enriched composition (Zr/Ti=97/3%). We have studied the performance dependence on sample thickness and working frequency, the main relevant parameters for a given PZT composition. The observed optimum values of efficiency and power output are analyzed in terms of the two main characteristic relaxation times of the process, the thermal time (sample thickness dependent) and the electric time (thickness independent). Possible ways of improving the overall performance are discussed.