Enhanced Electrical Transport and Magnetic Properties in La _0.67 Ca _0.33 Mn _0.97 Ni _0.03 O ₃ : Ag _x Ceramic Mediated by Ag Addition

ABSTRACT Perovskite material La 1‐ x Ca x MnO 3 exhibits broad application prospects in functional ceramics due to its distinctive physical properties, such as metal–insulator transitions and colossal magnetoresistance. However, its relatively low resistivity and magnetoresistance values near room temperature have limited its practical applications in devices including uncooled infrared detectors and magnetic storage systems. To address this, the introduction of highly conductive metals has been proposed as an effective approach to enhance both electrical and magnetic performance. In this study, La 0.67 Ca 0.33 Mn 0.97 Ni 0.03 O 3 : Ag x ( x = 0.05, 0.1, 0.15, 0.2, 0.25) composite ceramics were synthesized using a combined sol‐gel and solid‐state reaction method. The effects of Ag incorporation on the microstructure, electrical transport, and magnetoresistive properties were systematically investigated. Results demonstrate that Ag compositing significantly improves the temperature coefficient of resistance (TCR) and magnetoresistance (MR). The sample with x = 0.05 achieves a peak TCR of 56.7%·K −1 and a maximum MR of 78.1%. These findings underscore the efficacy of Ag compositing in enhancing the functional properties of manganite ceramics, showing considerable promise for applications in radiometric and magnetic sensing devices.