Study On The Preparation And Properties Of Bismuth Layered Photoelectric Multi-functional Ceramics

Bismuth layered photoelectric multifunctional ceramics?BLSFs?have received significant attention and became a hot topic for researchersat home and abroad for their promising applications in high temperature and high frequency photoelectric field because of their high Curie temperature,low dielectric constant,good temperature stability and excellent photoluminescence properties.In this paper,rare earth luminescent ions doped bismuth layered lead-free piezoelectric ceramics were prepared by a conventional solid-state reaction method and investigated their structure and photoelectric properties.This study lay a foundation for the high performance bismuth layered photoelectric functional ceramics.The main research content is as follows:?1?.The rare earth(RE³⁺)ions,such as Eu³⁺?Ho³⁺?Sm³⁺?Pr³⁺?Er³⁺,modified the Bi³⁺ions of the SrBi₄Ti₄O₁₅?SBT?system.Results show that,all SBT ceramics formed a typical bismuth layer structure and a dense microstructure with the plate-like gain morphology.Meanwhile,the SBT ceramics doped with RE³⁺ions can improve the ceramic samples of electrical properties and temperature stability,and make ceramics exhibit different photoluminescence properties.Upon the excitation of 465 nm light,the Eu³⁺doping make the ceramic samples present bright orange light,and the optimum electric properties can be obtained at the doping amount of 0.004:T_c=524^oC,tan?=0.90%,d₃₃=21pC/N,2P_r=22.29?C/cm² and high temperatures resistivity and good temperature stability.Under the 451 nm light excitation,the Ho³⁺doping make the ceramic samples present bright green light,and the optimum electric properties can be obtained at x=0.008:d₃₃=22pC/N,2P_r=28.31?C/cm²,tan?=0.87%and the excellent temperature stability.Under the 407 nm light excitation,the Sm³⁺doping make the ceramic samples present bright orange light,and the optimum electric properties can be obtained at x=0.006:d₃₃=19pC/N,2P_r=22.23?C/cm².Under the 450 nm light excitation,the Pr³⁺doping make the ceramic samples present bright orange red light,and the optimum electric properties can be obtained at x=0.002:d₃₃=20pC/N,2P_r=22.78?C/cm² and high temperatures resistivity and good temperature stability.Under the NIR 980 nm excitation,the Er³⁺doping make the ceramic samples present bright green up-conversion light,and the optimum electric properties can be obtained at x=0.008:d₃₃=17pC/N,2P_r=14.92?C/cm².?2?.The rare earth(RE³⁺)ions Ho³⁺and Eu³⁺modified the Sr²⁺ions of the SrBi₂Ti₂O₉?SBN?system.Results show that,a small amount of Ho³⁺make the main diffraction peak?115?of the SBN ceramic shift to the higher angle,and all SBN ceramics formed a dense microstructure with the plate-like gain morphology.At 0.004,samples exhibit optimal electrical properties with T_c=441^oC,2P_r=15.54?C/cm²,d₃₃=19pC/N,?_rd=93.60%and high temperatures resistivity and good temperature stability.At the same time,the ceramic samples appear bright green photoluminescence light under the 451 nm excitation.Althought the phase structure and microstructure have a little influence by Eu³⁺doping,the relative density of the ceramic continued to increase.At x=0.006,samples exhibit excellent performance:?_rd=92.07%,d₃₃=14pC/N,2P_r=11.97?C/cm²,together with good thermal stabilities and high resistivity.At the same time,samples obtained excellent photoluminescence properties by Eu³⁺doping.?3?.The?Pr,Ce?co-modified Bi³⁺ions of the NBT piezoelectric ceramics.After?Pr,Ce?doping,the phase structure and microstructure have no obvious changes.And the Curie temperature and ferroelectric properties of ceramics have been enhanced.Additionally,NBT ceramics exhibited bright photoluminescence properties by Pr³⁺doping.Samples possess bright red luminescent properties under the 492 nm excitation.