Effect of dispersant sodium dodecylbenzene sulfonate content on electrical transport properties of La0.67Ca0.33MnO3 ceramics

Perovskite manganite La 1 − x Ca x MnO 3 holds promising for uncooling infrared bolometers and magnetic sensors applications due to its unique properties such as metal insulator transition and colossal magnetoresistance. However, obtaining large temperature coefficient of resistance (TCR) value and magnetoresistance (MR) value in the temperature range close to room temperature remains a huge challenge. The dispersant can improve the agglomeration of particles in the precursor during the preparation of such ceramic materials, so that the uniformity of the samples is higher. In this study, we compare the effects of dispersants sodium dodecylbenzene sulfonate (SDBS) content on the structure, morphology, and electrical transport properties of La 0.67 Ca 0.33 MnO 3 (LCMO). We found that the ceramics with appropriate addition of SDBS possess higher density and larger grain size. Appropriate addition of SDBS can significantly improve the TCR and MR of the ceramics. The peak TCR reached 28.8%·K −1 ( x  = 2%), and the peak MR reached 57.6% ( x  = 4%). Our findings can promote the potential application of this material in infrared detect and magnetic sensors.