Canted antiferromagnetism in copper oxide nanoparticles synthesized by the reverse-micellar route

Copper oxide nanoparticles were synthesized by water-in-oil microemulsions with two different apolar solvents (isooctane and n-octane). Our studies on the samples show that the grain size is highly dependent on the nature of non-polar solvent, 25-30 and 80-90 nm sized nanoparticles with isooctane and n-octane, respectively. The Neel temperature of CuO nanoparticles obtained from isooctane is about 80 K. For the larger particles obtained from n-octane, the transition temperature shifts to higher temperature (similar to 220 K) near that of the bulk. (c) 2005 Elsevier SAS. All rights reserved.