报告题目：Piezoelectric Polymers and Ceramic-Polymer Nanocomposites
报告人：Prof. Qing Wang (Department of Materials Science and Engineering, The Pennsylvania State University, University Park )
Flexible piezoelectric materials are pivotal to a variety of emerging applications ranging from wearable electronic devices, sensors to biomedical devices. In this talk, I will present our latest results on the scalable ferroelectric ceramic-polymer composites based on three-dimensional (3-D) interconnected microfoams. The 3-D polymer composite exhibits exceptional piezoelectric characteristics under multiple loading conditions (i.e., compression, stretching, and bending) and high mechanical durability under thousands of cycles. The 3-D polymer composite also displays excellent pyroelectricity, thereby enabling concurrent thermal and mechanical energy scavenging. In addition, I will present our efforts on the development of the ferroelectric polymers exhibiting the state-of-the-art piezoelectric coefficient based on the concept of morphotropic phase boundary (MPB). Our work represents the discovery of MPB in the ferroelectric polymers and provides a unique molecular engineering approach to MPB. We have also successfully addressed the controversies in the fundamental understandings of the origin of piezoelectricity in ferroelectric polymers, which has plagued the field despite extensive studies during the past decades.