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

PTCR（正温度电阻系数）和执行器以及传感器器件的大多数材料都是基于含铅陶瓷。其主要缺点是铅和含铅化合物有毒，对人体和环境有害。在加工过程中，氧化铅（PbO）由于其高挥发性而释放，随着对这类功能材料的需求不断增加，可持续处理成为一个重要问题。世界各地的政府立法都推动了对可持续无铅功能材料的探索。这已成为工程科学中最具挑战性的课题之一。其中，钛酸钡基陶瓷和钛酸铋钠基陶瓷作为可能的替代品引起了科学界的广泛兴趣。尽管有广泛的研究和法规，含铅成分仍然是PTCR，执行器和传感器应用中最常见的材料。该项目的目的是了解供体掺杂对bt基无铅替代功能材料的PTCR和压电性能的影响，并为这类新材料的开发和实施提供指导。重点将是定义缺陷的化学性质和应变机制。

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.