Abstract. Copper nanoparticles with a mean carbon coating of about 1 nm were continuously produced at up to 10 g h⁻¹ using a modified flame spray synthesis unit under highly reducing conditions. Raman spectroscopy and solid state ¹³C magic angle spinning nuclear magnetic resonance spectroscopy revealed that the thin carbon layer consisted of a sp²-hybridized carbon modification in the form of graphene stacks. The carbon layer protected the copper nanoparticles from oxidation in air. Bulk pills of pressed carbon/copper nanoparticles displayed a highly pressure- and temperature-dependent electrical conductivity with sensitivity at least comparable to commercial materials. These properties suggest the use of thin carbon/copper nanocomposites as novel, low-cost sensor materials and offer a metal-based alternative to the currently used brittle oxidic spinels or perovskites.

Print publication: Issue 6 (28 March 2006)
Received 9 January 2006, in final form 30 January 2006
Published 27 February 2006