Superior Energy Storage Capability and Fluorescence Negative Thermal Expansion of NaNbO₃‐Based Transparent Ceramics by Synergistic Optimization

Abstract

Transparent dielectric ceramics are splendid candidates for transparent pulse capacitors (TPCs) due to splendid cycle stability and large power density. However, the performance and service life of TPCs at present are threatened by overheating damage caused by dielectric loss. Here, a cooperative optimization strategy of microstructure control and superparaelectric regional regulation is proposed to simultaneously achieve excellent energy storage performance and real‐time temperature monitoring function in NaNbO3‐based ceramics. By introducing aliovalent ions and oxides with large bandgap energy, the size of polar nanoregions is continuously reduced. Due to the combined effect of increased relaxor behavior and fine grains, excellent comprehensive performances are obtained through doping appropriate amounts of Bi, Yb, Tm, and Zr, Ta, Hf in A‐ and B‐sites of the NaNbO3 matrix, including recoverable energy storage density (5.39 J cm−3), extremely high energy storage efficiency (91.97%), ultra‐fast discharge time (29 ns), and superior optical transmittance (≈47.5% at 736 nm). Additionally, the phenomenon of abnormal fluorescent negative thermal expansion is realized due to activation mechanism of surface phonon at high temperatures that can promote the formation of [Yb···O]‐Tm3+ pairs, showing great potential in real‐time temperature monitoring of TPCs. This research provides ideas for developing electronic devices with multiple functionalities.

High energy storage density achieved in BNT‐based ferroelectric translucent ceramics under low electric fields

“…Furthermore, as electronic components continue to miniaturize and integrate, the development of ceramic dielectric capacitors with both energy storage capabilities and transparency could potentially broaden their applications in various fields, such as high-power laser windows and security monitors. 17 However, reports on leadfree transparent ferroelectric ceramics primarily focus on KNN-based materials. [18][19][20] While the excellent energy storage performance of lead-free BNT-based ceramics has been widely reported, its narrow optical bandgap has received little attention regarding its transparency.…”