LEAD-FREE PIEZOELECTRIC MATERIALS: A STUDY ON SILK FIBROIN-ZnO HYBRID FILMS FOR FLEXIBLE SENSING APPLICATIONS

Abstract

The widespread use of lead and its derivatives as piezoelectric materials has been causing immense environmental and notable public health issues. Herein, we are principally going to review lead-free piezoelectric materials. It is well known that Lead zirconate titanate (PZT) is prominent for its dominating piezoelectric qualities, but the primary cause of lead's extended environmental persistence is its non-biodegradable nature. Presently, several materials are being explored as potentially appealing PZT substitutes for particular uses. This study examines recent advances in lead-free materials, including ZnO nanostructures, inorganic ceramics such as barium titanate (BT), sodium potassium niobate (KNN), sodium bismuth titanate (BNT), bismuth layer-structured ferroelectrics (BLSFs), and polymers like PVDF and PVDF-TrFE. It focuses on their biocompatibility, high electromechanical coupling factor, and stable electrical properties, focusing on preparation, structure–property correlation, and finding promising applications in bioengineering, military, optoelectronic information, and energy. Lastly, the difficulties and viewpoints surrounding lead-free piezoelectric materials and devices are discussed.