Abstract
Room temperature ferromagnetism (RTF) is observed in pure copper oxide (CuO) nanoparticles which were prepared by precipitation method with the post-annealing in air without any ferromagnetic dopant. X-ray photoelectron spectroscopy (XPS) result indicates that the mixture valence states of Cu1+ and Cu2+ ions exist at the surface of the particles. Vacuum annealing enhances the ferromagnetism (FM) of CuO nanoparticles, while oxygen atmosphere annealing reduces it. The origin of FM is suggested to the oxygen vacancies at the surface/or interface of the particles. Such a ferromagnet without the presence of any transition metal could be a very good option for a class of spintronics.
Highlights
Integration of semiconductor with ferromagnetic function has been focused on in spintronics because of the difficulties associated with the injection of spins from magnetic metal into nonmagnetic semiconductors in conventional spintronic devices
Room temperature ferromagnetism (RTF) is observed in pure copper oxide (CuO) nanoparticles which were prepared by precipitation method with the postannealing in air without any ferromagnetic dopant
X-ray photoelectron spectroscopy (XPS) result indicates that the mixture valence states of Cu1? and Cu2? ions exist at the surface of the particles
Summary
Integration of semiconductor with ferromagnetic function has been focused on in spintronics because of the difficulties associated with the injection of spins from magnetic metal into nonmagnetic semiconductors in conventional spintronic devices. CuO, as a narrow band gap p-type semiconductor, has been recognized as an industrially important material for a variety of practical applications, such as catalysis, batteries, solar energy conversion, gas sensing, and field emission [12–14]. The synthesis and study of CuO nanostructures should be of practical and fundamental importance. Xiao et al and Shang et al [17, 18] reported the observation of RTF in CuO nanostructures. The FM in CuO remains controversial because most groups suggested that Cu atoms have no clustering tendency and Cu-based oxides are not ferromagnetic [19, 20]. We synthesize CuO nanoparticles by a simple co-precipitation method to avoid the influences of substrate and the interface between film and substrate [21]. We found the CuO nanoparticles show RTF, and the origin of the FM is discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
