Barium titanate crystal is a dielectric ceramic with high dielectric constant and low dielectric loss, which is widely used in electronic and energy harvesting fields because of its excellent iron, thermal, optical and piezoelectric properties. HoweverBTOThe brittleness of crystal limits its application in the field of flexible electronics,Therefore, the development of flexible processingBTOEffective methods for blocks or films are of great interest. An effective way to make flexible crystals is to construct fiber structures with high aspect ratios,Since chipping and fracture easily occur at grain boundaries, the crystal size should be refined to enlarge these grain boundaries.

Whencrystal fiberWhen bent, complex grain boundaries can reduce crack propagation and prevent fiber breakage, which is often referred to as the pinning effect. Methods of preparing crystalline fibers include laser cutting,Vapor deposition, electrospinning, etc.,In these methods, electrospinning due to its versatility of the raw material of the fiber,High strain tolerance and particle size controllability are widely used. Especially when the diameter of the crystal fiber is reduced from the micron level to the nanometer level, the size effect brought by the diameter thinning will give the nanofiber material many unique mechanical, thermal and electrical properties. However, it is very challenging to process flexible multicomponent oxide ceramic crystal nanofibers.,due to the presence of many inconsistent grain boundaries. Therefore, the controlled preparation of flexible ternary.BTOcrystal fiberIt will be a breakthrough in the field of ceramic crystallography.

Recently, the Institute reported a sol-based-A simple and inexpensive polymer template synthesis method for gel electrospinning and high-temperature calcination processes to obtain flexibleBTOcrystal fiber. Based on the properties of spinning solution, the parameters of electrospinning and the control of calcination conditions, the dynamic evolution of colloidal particles in the calcination process andBTOCrystal transformation, grain growth and pore structure evolution process, a comprehensive study of the grain size and grain boundary is closely related to the flexible deformation mechanism. The deformation mechanism of single fiber and fiber membrane in the process of bending force is discussed, the microstructure theory affecting the flexibility of ceramic nanofibers is proposed, and the flexible mechanism of ceramic nanofibers is revealed. PreparedBTOCrystalline fibers have polymer-like lightness, silky softness, and a large Young's modulus. In addition, the crystal fibers also showed0.9%of the elastic strain. FlexibleBTOThe ceramic crystal film can effectively reduce the vibration to adapt to the risk of cracking during large deformation. In this way, a high sensitivity piezoelectric sensor can be designed.100 SMAunder pressure, can be provided80 msFast response time,1.05Vhigh output voltage and4.8 Naof the current.

In summary, the researchers through the sol-Flexible barium titanate nanoparticles were prepared by gel electrospinning and high temperature calcinationcrystal fiberFilm. Perovskite-type barium titanate crystals with complex grain boundaries can be formed at lower temperatures by growth in polymer templates. The Young's modulus of the ceramic membrane is61 MPa, softness is50 mNand the elastic strain is0.9%. In addition, their density is as low28milligram centimeter-3It will not break after deformation. Piezoelectric sensors based on these films are used in100under pressure of kPa1.05Volt output voltage and80Millisecond sensitivity,The method allows large-scale fabrication of flexible barium titanate crystalsNFFilm.