JENG-WEI CHEN2018-09-102018-09-10201100255408http://www.scopus.com/inward/record.url?eid=2-s2.0-79960994797&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/363860The dielectric properties and impedance spectroscopy (IS) of perovskite SmFeO3 ceramics were studied in the frequency range of 100 Hz-1 MHz in the temperature range from 80 K to 300 K. These materials exhibited colossal dielectric constant of ∼104 at room temperature. The response is similar to that observed for relaxor-ferroelectrics. IS data analysis indicates the ceramic to be electrically heterogeneous semiconductor consisting of semiconducting grains with dielectric constant 20 and more resistive grain boundaries. We conclude, therefore that grain boundary effect is the primary source for the high effective dielectric constant in SmFeO3 ceramics. © 2011 Elsevier Ltd. All rights reserved.A. Ceramics; B. Sol-gel chemistry; C. Impedance spectroscopy; D. Dielectric propertiesA. Ceramics; B. Sol-gel chemistry; C. Impedance spectroscopy; Colossal dielectric constant; D. Dielectric properties; Effective dielectric constants; Frequency ranges; Grain boundary effects; High dielectric constants; Impedance spectroscopy; Primary sources; Room temperature; Semiconducting grains; Temperature range; Ceramic materials; Data reduction; Dielectric properties; Grain boundaries; Grain size and shape; Perovskite; Semiconductor insulator boundaries; Dielectric materialsjournal article10.1016/j.materresbull.2011.06.0012-s2.0-79960994797WOS:000294520500024