Growth Mechanism and Magnetic Properties of Highly Crystalline NiO Nanocubes and Nanorods Fabricated by Evaporation

• Published in: Crystal growth & design Vol. 12; no. 6; pp. 2842 - 2849
• Main Authors: Chen, Da-Peng, Wang, Xiao-Lin, Du, Yi, Ni, Song, Chen, Zi-Bin, Liao, Xiaozhou
• Format: Journal Article
• Language: English
• Published: Washington,DC American Chemical Society 06.06.2012
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Methods of crystal growth; physics of crystal growth; Methods of nanofabrication; Nanoscale materials and structures: fabrication and characterization; Other topics in nanoscale materials and structures; Physics; Quantum wires; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Theoretical study; Ferromagnetic materials; Evaporation; Melting points; Heat treatments; Surface states; Morphology; Growth mechanism; Nanorod; Nanostructured materials; Nanocrystal; Nickel oxide; Nanomaterial synthesis; Magnetic properties
• ISSN: 1528-7483; 1528-7505
• DOI: 10.1021/cg201676u

A new approach to the preparation of regularly shaped NiO nanocubes and nanorods by an infrared heating evaporation method is presented. The growth model is proposed to be a vapor–solid mechanism. The morphology of the nanocrystals can be tuned by the carrier gas flow rate. The samples consist of nanocrystals that are highly crystallized with atomic-scale smooth surfaces. This novel method could be extended to nanocrystal growth of other oxides with low volatility or high melting points. The results of magnetic characterization indicate that the NiO nanorods and nanocubes grown from a mixed target both show weak ferromagnetic states at low and room temperature due to uncompensated spins at the surfaces of the nanocrystals.