Dr. Chen Xiaogang of Southeast University reported for the first time the two-dimensional layered perovskite ferroelectrics with super large piezoelectric voltage coefficient

Recently, Chen Xiaogang, Ph.D student of International Institute of molecular ferroelectric science and application and Jiangsu Provincial Key Laboratory of molecular ferroelectric science and application, School of chemistry and chemical engineering, Southeast University, published "two dimensional layered perovskite ferroelectric with giant piezoelectric voltage" on the top journal of the American Chemical Society Coefficent It is the first time to report the two-dimensional layered perovskite ferroelectrics with large piezoelectric voltage coefficient, which represents another important stage of molecular ferroelectrics in piezoelectric field High performance intelligent sensor which can adapt to various environmental conditions is one of the core researches in the field of information technology Among them, piezoelectric sensor has been widely concerned because of its advantages of fast response time, wide working temperature range, high stability, regeneration and insensitivity to electric and magnetic fields From the practical point of view, the key performance parameters of the piezoelectric sensor include the piezoelectric voltage coefficient g 33 as the material quality factor and the Curie temperature Tc which determines the use temperature range Since piezoelectricity was discovered in 1880, the traditional inorganic Perovskite Ferroelectric Ceramics with higher electrical strain coefficient D 33, such as BaTiO3 (BTO), lead zirconate titanate (Pb (Zr, Ti) O3, PZT) have been the mainstream of research and application, but its G33 is usually limited to 40 × 10-3 vn-1 or below This is due to the fact that in addition to the high D 33, the dielectric constant of the material is relatively low It has been found that the G 33 of ferroelectric polymer PVDF (polyvinylidene fluoride) can reach 286.7 × 10-3 vn-1, but its application is hindered by its low melting point, low crystallinity and high coercive field As a beneficial supplement to inorganic ferroelectrics and ferroelectric polymers, molecular ferroelectrics have the advantages of light weight, flexibility, easy preparation, environmental protection, and outstanding structural controllability, which also provides a theoretical material design platform for obtaining and modulating various properties through molecular modification and self-assembly strategies After many years of development, molecular ferroelectrics have caught up with or even surpassed inorganic ferroelectrics in terms of large spontaneous polarization, high Tc, high D 33 and other properties But the study of molecular ferroelectrics with larger g 33 is still a blank before Based on this, with the efforts of the research team of Southeast University, two-dimensional organic-inorganic hybrid perovskite ferroelectrics have been successfully designed and synthesized: [4-aminotetrahydropyran] 2 pbbr 4 Its G 33 is as high as 660.3 × 10-3 vn-1, more than twice as high as PVDF, and far beyond pzt In addition, the TC value of 503K (much higher than that of 393k of BTO) further guarantees that it can adapt to a wider application range This work shows the great application potential of molecular ferroelectrics in the field of new generation intelligent piezoelectric sensors The first author of this paper is Chen Xiaogang, Ph.D student, School of chemistry and chemical engineering, Southeast University, which is the first communication unit The research results are supported by the "top ten scientific and technological issues of Southeast University" start-up cultivation fund.