Research Progress on High Curie Point BaTiO₃ Based Lead-Free Positive Temperature Coefficient Thermosensitive Ceramics

The positive temperature coefficient (PTC) thermosensitive material is a semiconductor material that is very sensitive to temperatures, among which the BaTiO₃ based PTC thermosensitive ceramic is the most widely used. In order to meat the needs of high temperature use and lead-free green environmental protection requirements, the high Curie point BaTiO₃ based lead-free PTC thermosensitive ceramics has received great attention. Several common high Curie BaTiO₃ based lead-free PTC thermosensitive ceramics are introduced, and the modification methods, including donor doping, acceptor doping and process improvement, are reviewed. The current shortcomings of the materials are described, and the future development direction is prospected.