Enhanced thermistor performance of LaCrO3 through high-entropy strategy

Abstract

Lanthanum chromite (LaCrO3) based perovskites are crucial in advanced electronics for their stability, but efforts to enhance their density and structural stability remain vastly lacking. Here, we introduced high-entropy concept to enhance the microstructure and electrical properties of LaCrO3 for thermistor applications. The obtained La(Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)O3-δ and (La0.2Nd0.2Sm0.2Gd0.2Y0.2)(Cr0.2Mn0.2Fe0.2Co0.2Ni0.2)O3-δ ceramics showed high relative densities of up to 89.48 % and 99.57 %, respectively. The shear strain due to significant lattice distortions caused by differences in elemental size, mass and electronegativity increased resistivity through enhancing phonon scattering. Meanwhile, this strain effect and native defects changed the charge conduction mode, thus resulting in a significant linearity at critical temperatures exceeding 163 K. Our results reveal that the high-entropy enhances the performance of LaCrO3 materials for thermistor applications, especially in terms of improving the ceramic density, reducing the resistivity and enhancing the temperature sensing accuracy. This high-entropy approach is expected to be widely applicable for the development of high-performance low-temperature thermistors.