Ferroelectric composites are prepared by sol-gel derived procedures. The present invention utilizes a sol-gel process to form a gel in a mold of the desired size and shape ([1]-[4]), to dry the gel using a supercritical fluid extraction ([5]-[7]), to sinter the dried gel to a crystalline ceramic ([8]), and finally to impregnate the pores with a low loss polymer ([9]). The aerogel composition may be a barium titanate-based composition such as barium strontium titanate (BST). Making a ferroelectric aerogel composite provides a unique and novel means of fully exploiting the voltage- and/or frequency-tunable properties of certain compositions by maximizing their desirable properties and minimizing their undesirable characteristics such as loss at operational frequencies (Fig. 2).
铁电复合材料是通过溶胶-凝胶衍生工艺制备的。本发明利用溶胶-凝胶法在所需尺寸和形状的模具中形成凝胶([1]-[4]),使用超临界流体萃取法干燥凝胶([5]-[7]),将干燥的凝胶烧结成结晶陶瓷([8]),最后用低损耗聚合物浸渍孔隙([9])。气凝胶成分可以是
钛酸钡基成分,如
钛酸锶钡(BST)。制作
铁电气凝胶复合材料为充分利用某些成分的电压和/或频率可调特性提供了一种独特而新颖的方法,即最大限度地提高其理想特性,同时最大限度地降低其不良特性,如工作频率下的损耗(图 2)。