A novel method for fabrication of highly porous barium strontium titanate (BST) ceramic foams based on particle-stabilized foaming method was developed for the first time, in which propyl gallate (PG) was employed as BST particle modifier. The results showed that the stability of wet BST foams closely depends on the pH value and PG concentration, which could be explained by the adsorption behavior of PG on BST particle surface. BST ceramic foams with dense, uniform, and closed pore and defect-free wall were obtained. The pore size and porosity can be well controlled by adjusting solid loading and sintering temperature. It was revealed that not only sintering temperature but also solid loading significantly influenced the growth of BST grain. The BST ceramic foams exhibited high porosity in the range of 81%-95%, low dielectric constant in the range of 47-150, and low dielectric loss below 0.0025. The BST ceramic foams with higher porosity presented a tendency of lower dielectric constant and the fitting results indicated that the natural logarithm of dielectric constant was linear correlated with porosity.

中文翻译：

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粒子稳定泡沫产生的介电常数低的高孔隙度钛酸锶钡（BST）陶瓷泡沫

首次开发了一种基于颗粒稳定发泡法的高孔隙度钛酸锶钡（BST）陶瓷泡沫的新型制备方法，该方法采用没食子酸丙酯（PG）作为BST颗粒改性剂。结果表明，湿式BST泡沫的稳定性与pH值和PG浓度密切相关，这可以用PG在BST颗粒表面的吸附行为来解释。获得了具有致密，均匀，封闭的孔和无缺陷壁的BST陶瓷泡沫。孔径和孔隙率可以通过调节固体负载和烧结温度来很好地控制。结果表明，不仅烧结温度，而且固含量也显着影响BST晶粒的生长。BST陶瓷泡沫在81％-95％的范围内显示出高孔隙率，介电常数在47-150范围内，介电损耗在0.0025以下。孔隙率较高的BST陶瓷泡沫呈现出较低的介电常数趋势，拟合结果表明介电常数的自然对数与孔隙率呈线性关系。