A novel environmentally friendly linear thermistor in the xAl₂O₃-(1-x)ZnO composite

The negative temperature coefficient (NTC) thermistor, known for its high sensitivity and rapid response, plays a crucial role in various sectors such as the national economy, military, and aerospace. Linear NTC thermistors can simplify circuit design, but most linear NTC thermistors used today use expensive, heavy, and harmful metals. As such, researching environmentally friendly NTC thermistors with linear temperature resistance characteristics is crucial for environmental protection and advancement of high-performance electronic ceramics. This paper discusses the synthesis of environmentally friendly linear thermistor materials in the xAl₂O₃-(1-x)ZnO composite using the solid-phase reaction method. By introducing the high-resistance phase Al₂O₃, a three-dimensional conductive composite of ZnAl₂O₄ and ZnO was formed. This composite exhibited excellent linear negative temperature coefficient resistance–temperature characteristics spanning from 343 to 513 K. The highest linearity (R² = 0.9984) was observed when x = 0.05.