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SrCu3Ti4O12, La2/3Cu3Ti4O12, and Bi2/3Cu3Ti4O12 ceramics were representatively investigated to obtain a systematical understanding about the dielectric behaviors of the compositionally and structurally CaCu3Ti4O12‐like oxides and the underlying related mechanism. In opposite to the literature results, giant dielectric‐permittivity phenomena with low‐frequency ɛ′ larger than 1.5 × 104 have been observed in all of these ceramics. Furthermore, the existence of CuO secondary phase has been confirmed in them. In general, the results can be explained by the similar mechanism of internal barrier layer capacitance effect formerly proposed for CaCu3Ti4O12 ceramics and indicate that the giant‐ɛ′ phenomena should be quite common in the large family of compositionally and structurally CaCu3Ti4O12‐like oxide ceramics.

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Inspired by the hierarchical structure of nacre, lots of functional nanocomposite films have been fabricated through finely tuning the composition and structure. To broaden their application in biological and biomedical research, it is highly demanded to develop a new strategy to fabricate nanocomposite films that are both biocompatible and functional. Herein, hyperbranched poly(amido amine)s (HPAMAMs) have been assembled with clay nanosheets. The obtained nanocomposite films show good mechanical performance and fluorescence properties. Analysis of the structure of the nanocomposite films indicates that the HPAMAMs and the clay nanosheets are stacked together in an orderly manner. The clay nanosheets align in the direction parallel to the film surface. Because of the inherent biocompatibility and autofluorescence property of the HPAMAMs, such composite films are thought to be very promising in applications requiring biocompatibility, fluorescence, and good mechanical performance. The method should provide a new route to the fabrication of functional nacrelike composite materials.[a] Prof.