Influence of Annealing Temperature on Berthelot-Type Hopping Conduction Mechanism in Carbon-Nickel Composite Films. (May 2016)

• Record Type: Journal Article
• Authors: Dalouji, V.; Elahi, S. M.; Ghaderi, A.; Solaymani, S.
• Is Part Of: Chinese physics letters. Volume 33:Number 5(2016:May)
• Publication Date: 2016-05
• Subjects: 72.15.Eb -- 66.70.Df; Physics -- Periodicals; Electronic journals; 530.05
• DOI: 10.1088/0256-307X/33/5/057203
• Languages: English
• ISSNs: 0256-307X

Abstract

Abstract : Electrical conductivity of carbon-nickel composite films annealed at temperatures 300, 500 and 800°C is studied over a temperature range of 50–300 K. While the conductivity data above room temperature show extended state conduction, lowering the temperature from 150 to 50 K leads to the Berthelot-type conduction mechanism. It can be seen that the films annealed at 500°C have the maximum conductivity. The extent of the carrier wave function at 500°C has the minima 2.87 × 10 −7 cm and 2.45 × 10 −7 cm in octahedral-metal stretching vibrations and intrinsic stretching vibrations of the metal at the tetrahedral site, respectively. The average distances between two vibration octahedral and tetrahedral sites at 500°C also have the minima 1.13 × 10 −7 cm and 0.97 × 10 −7 cm, respectively. The Berthelot temperature for films annealed at 800°C has the minimum of 94.3 K.