A novel (Sm0.2Eu0.2Gd0.2Ho0.2Yb0.2)CrO3 high-entropy ceramic nanofiber as a negative temperature coefficient thermistor

The electrical properties of high-entropy ceramics (HECs) have been extensively studied in recent years due to their unique structural characteristics and fascinating functional properties induced by entropy engineering. Novel high-entropy (Sm0.2Eu0.2Gd0.2Ho0.2Yb0.2)CrO3 (HE-RECrO3) nanofibers were prepared by electrospinning. This work demonstrates that HE-RECrO3 nanofibers were successfully synthesized at a low temperature (800 °C), which is approximately 400 °C lower than the temperatures at which chromate ceramics were synthesized via the sol–gel method and the solid–state reaction method. The resistivity of HE-RECrO3 nanofibers decreases exponentially with increasing temperature from 25 to 600 °C. The logarithm of the resistivity is linearly related to the inverse of the temperature, confirming the negative temperature coefficient property of HE-RECrO3 nanofibers. The B25/50 value of the HE-RECrO3 nanofibers reaches 4072 K. In conclusion, HE-RECrO3 nanofibers are expected to be potential candidates for negative-temperature-coefficient (NTC) thermistors.