A Brief introduction of the Speaker
Dr Haixue Yan works on high temperature piezoelectric, Spark Plasma Sintering (SPS), phase transitions in ferroelectrics. He reported for the first-time ferroelectricity and piezoelectricity in layer-structured A2B2O7 ceramics with super-high Curie points (>1450 ℃). This work has produced a step-change in the operating temperature of piezoelectric sensors. His work on SPS has demonstrated that nano particles can work as building blocks during fast sintering. His work on ferroelectric characterization has provided evidences to answer open questions on phase transitions in lead-free ferroelectrics including Bi0.5Na0.5TiO3, NaNbO3 and AgNbO3-based dielectrics. Recently his research has focused on high entropy ferroelectric ceramics for dielectric and/or piezoelectric applications. His recent work also covers THz probing dielectrics and high entropy ceramics.
He is on the editorial board of Scientific Reports, Advance in Applied Ceramics, Material Research Bulletin and Journal of Advanced Ceramics. Dr. Yan is an FIMMM and FRSC. He has 9 patents and >250 publications in peer-reviewed journals with an H-index of 59. He regularly gives invited/keynote talks in international conferences.
Abstract
Due to the worldwide concerns of environmental protection and sustainable development, lead-free ferroelectric materials are greatly desired to replace lead-based PZT ferroelectrics for dielectric and piezoelectric applications. Bi0.5Na0.5TiO3 (BNT) system shows promising dielectric and piezoelectric properties and the properties are related to phase transitions under applied electrical field. There are different models in literature to explain the transition mechanism. In this talk, we will review the reported phase transitions models and explain their links to improved dielectric and piezoelectric properties. Specifically, we will focus on dielectrics for high power energy storage, piezoelectric sensors with increased thermal stability and piezoelectric actuators with high field-induced strain.
