Synthesis and Performance Characterization of Pyroelectric Lithium Tantalate Coatings

[Background]: The operation of marine reactors and floating nuclear power plants is challenged by the thermal fluctuation of heat transfer surfaces caused by oceanic motion. The pyroelectric effect of lithium tantalate (LT), a material that changes its spontaneous polarization with temperature variations, has the potential to influence the wettability of surfaces, thereby improving heat transfer performance. [Purpose]: This study aims to prepare LT coatings with controlled pyroelectric properties and to investigate the mechanism by which these properties can regulate the wettability of surfaces, thereby enhancing heat transfer efficiency in two-phase systems. [Methods]: The sol-gel method was used to achieve the controlled synthesis of LT, and the pyroelectric effect and mechanism of wettability modulation were investigated by the change of hydroxyl radical. [Results]: The results indicate that the crystallinity, particle size, and thickness of the coatings can be regulated by adjusting the synthesis parameters and the particle size of LT increases with increasing annealing temperature. The pyroelectric characteristics are significantly influenced by the thickness and particle size of the coatings, with increased thickness and decreased particle size both contributing to enhanced pyroelectric performance. Fluorescence spectroscopy analysis shows that the hydroxyl radical concentration of LT increases during the heating process, and it also confirms that LT has the ability to regulate the hydroxyl radical concentration when undergoing heating and cooling cycles. [Conclusions]: In conclusion, LT coatings have temperature-dependent wettability in two-phase system with variable temperature.