College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China.
Dalton Trans. 2018 Jul 17;47(28):9257-9266. doi: 10.1039/c8dt01628c.
In this study, (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 (BCTZ) lead-free ceramics with enhanced energy density were prepared by two-step sintering. All ceramics fall into the rhombohedral-orthorhombic-tetragonal (R-O-T) phase boundary near room temperature, and a dense microstructure with an intermediate grain size was observed. The enhanced piezoelectric and energy harvesting properties were attained over a wide grain size range of 10-15 μm, benefiting from the construction of the R-O-T phase boundary. Most interestingly, the maximum values of d33 and d33 × g33 (530 pC N-1 and 9720 × 10-15 m2 N-1) can be achieved at 1500/1350 °C with a grain size of 13.7 μm. The interpretation of the underlying mechanism related to domain and defect engineering has been investigated systematically. Furthermore, a high output power of 99 μW and an energy conversion efficiency of 10% were obtained at a simple cantilever energy harvester fabricated from a 1500/1350 °C specimen under an acceleration of 1.0g, making the current system very promising for piezoelectric energy harvesting applications.
本研究采用两步烧结法制备了具有高储能密度的（Ba0.85Ca0.15）（Ti0.9Zr0.1）O3（BCTZ）无铅陶瓷。所有陶瓷均落入室温附近的三方-正交-四方（R-O-T）相变区，观察到具有中等晶粒尺寸的致密微观结构。在 10-15μm 的宽晶粒尺寸范围内，获得了增强的压电和能量收集性能，这得益于 R-O-T 相变区的构建。最有趣的是，在晶粒尺寸为 13.7μm 时，在 1500/1350℃下可获得最大的 d33 和 d33×g33（530pC N-1 和 9720×10-15m2 N-1）值。系统研究了与畴和缺陷工程相关的基础机制的解释。此外，在 1.0g 加速度下，由 1500/1350℃样品制成的简单悬臂式能量收集器可获得 99μW 的高输出功率和 10%的能量转换效率，这使得电流系统非常有前途用于压电能量收集应用。
