Materials Chemistry and Physics, Vol.148, No.1-2, 305-310, 2014
Nickel oxide coated carbon nanoparticles as temperature sensing materials
In this research, carbon black nanoparticles were coated with nickel oxide chemically to prepare composite materials with a large temperature coefficient of resistance (TCR) and low resistivity for thermistor applications. Carbon black (CB) nanoparticles were first suspended in aqueous nickel chloride solution. After titrating with sodium hydroxide, nickel hydroxide was chemically depositing onto carbon black nanoparticles. The precipitates were filtered, collected, and calcined at 300 degrees C to generate NiO/CB composites. The XRD results for the NiO/CB composites showed distinct NiO crystalline structures with an average grain size of 12 nm. Surface morphology of prepared elements was also examined with SEM to show that the CB particles were coated by NiO. The electrical resistivity of the composite NiO/CB material follows Arrhenius relation with activation energy of 0.38 eV in the range of 50-200 degrees C and possesses a high temperature sensitivity with B-values more than 4000 K. (C) 2014 Elsevier B.V. All rights reserved.