Structural and electrical properties of NixMn3 (-) O-x(4) system ceramics for infrared sensors

Abstract

In this study, NixMn3-xO4 ceramics were prepared using a conventional mixed oxide method for application in infrared sensors, and the dried powder was calcined at 900 degrees C for 2 h. All specimens were sintered in air at 1200 degrees C for 12 h and annealed at a rate of 2 degrees C/min to 800 degrees C, subsequently quenching to room temperature. It has been shown that all specimens showed the formation of a cubic spinel phase without any second phase. From the surface micrographs and density results, all specimens showed a high density and low porosity. In terms of the temperature coefficient of resistance (TCR = 1/R*dR/dT), all specimens showed values -4%/degrees C above and the typical NTCR (negative temperature coefficient of resistance) properties, displaying decreased electrical resistance with an increase in temperature. The resistivity of the Ni0.79Mn2.21O4 specimen at room temperature was approximately 2602 Omega.cm. The responsivity and detectivity of the Ni0.79Mn2.21O4 ceramics sintered at 1200 degrees C were 4.56 * 10(-3) V/W and 2010 cm Hz(1/2)/W, respectively. (C) 2015 Elsevier B.V. All rights reserved.