Electrical and thermal conductivities of rare-earth A2Zr2O7 (A = Pr, Nd, Sm, Gd, and Er)


  • A. Quiroz Universidad Tecnológica de Xicotepec de Juárez, Área Mantenimiento Industrial y Petróleo. Av. Universidad Tecnológica No. 1000, Col. Tierra Negra, C.P. 73080, Cd. Xicotepec de Juárez, Pue., Mexico
  • V. Garcia-Vazquez Instituto de Física Luis Rivera Terrazas, Benemérita Universidad Autónoma de Puebla, Apartado Postal J-48, Puebla, Pue., 72570, Mexico
  • C. Guarneros Aguilar CONACYT- Instituto Politécnico Nacional, Materiales y Tecnologías para Energía Salud y Medio Ambiente (GESMAT), CICATA Altamira, Km 14.5 Carretera Tampico-Puerto Industrial Altamira, 89600, Altamira, Tamaulipas, Mexico
  • R. Agustin-Serrano Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Av. San Claudio y 18 Sur, Ciudad Universitaria, Puebla, Pue. 72570 Mexico,
  • E. Chavira Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apartado Postal 70-360 Ciudad de Mexico, 04510 Mexico,
  • M. Abatal Facultad de Ingeniería Universidad Auto ́noma del Carmen, Av. Central S/N Esq. con Fracc. Mundo Maya, Ciudad del Carmen, Campeche, 24115 Mexico




Solid state chemistry, Thermal analysis, X-ray diffraction and scattering, Thermoelectrics, Zirconates


Structural and thermoelectric properties of rare-earth zirconates A2Zr2O7, with A = Pr, Nd, Sm, Gd, and Er, were studied. Samples were prepared by solid-state reaction at ambient pressure with temperatures between 1000 and 1400 °C. The resulting compounds were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM/EDS). The XRD analyses showed the formation of polycrystalline Pr2Zr2O7, Nd2Zr2O7, Sm2Zr2O7, Gd2Zr2O7 and Er2Zr2O7 phases, with a cubic cell (space group Fm3m) and traces of the raw used materials. The micrographs obtained by SEM show the formation of heterogeneous grains with a size that ranges from 0.7 to 4.7 μm. All A2Zr2O7 samples present porous surfaces. Thermal conductivities were measured at different temperatures, from 300 to 900 K. In most of the samples, the thermal conductivity monotonically decreases with temperature, from 0.40 – 1.17 W/mK at 300 K to 0.27 – 0.77 W/mK at 773.15 K. At a fixed temperature, the thermal conductivity decreases almost monotonically with the ionic radius (IR) of the rare-earth elements (where IR (Er3+) = 0.890 Å < IR (Gd3+) = 0.938 Å < IR (Sm3+) = 0.958 Å < IR (Nd3+) = 0.983 Å < IR (Pr3+) = 0.99 Å).


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How to Cite

A. Quiroz, V. Garcia-Vazquez, C. Guarneros Aguilar, R. Agustin-Serrano, E. Chavira, and M. Abatal, “Electrical and thermal conductivities of rare-earth A2Zr2O7 (A = Pr, Nd, Sm, Gd, and Er)”, Rev. Mex. Fís., vol. 67, no. 2 Mar-Apr, pp. 255–262, Jul. 2021.