BNT-BT as the future lead-free functional material for PTCR, actuator and sensor applications

• Applicant: Dr.-Ing. Jan Manuel Hinterstein
• Subject Area: Synthesis and Properties of Functional Materials
• Term: from 2015 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 276699501

Most of the materials for PTCR (positive temperature coefficient of resistance) and actuator as well as sensor devices are based on lead containing ceramics. The main drawback is that lead and lead-containing compounds are toxic and harmful to the human body and the environment. During processing, lead-oxide (PbO) is released due to its high volatility and, with increasing demand for such functional materials, sustainable disposal is becoming a significant issue. Governmental legislations all over the world have driven the search for sustainable lead-free functional materials. This has become one of the most challenging topics in engineering science. Amongst the promising systems, barium titanate based and bismuth sodium titanate based ceramics attracted wide interest in the scientific community as possible alternatives. Despite extensive studies and regulations, Pb-containing compositions are still the most common materials for PTCR, actuator and sensor applications. The aims of this project are to understand the influence of donor doping on the PTCR and piezoelectric properties of BT-based lead free alternative functional materials and to derive guidelines for the development and implementation of this new class of materials. The key focus will be to define the defect chemistry and strain mechanisms.

• DFG Programme: Independent Junior Research Groups