Transparent Cr-doped SnO 2 thin films: ferromagnetism beyond room temperature with a giant magnetic moment

Waczyński

Materials Science-Poland

et al. 2014

SnO 2 nanocrystalline thin films have been deposited on oxidized silicon substrates by spin-coating from a precursor solution, followed by slow thermal annealing in oxygen atmosphere at different temperatures (500 to 900°C). The precursor solution consisted of 1.0 to 2.0 M SnCl 4 ·5H 2 O in isopropanol. It was shown that the concentration of the precursor solution, annealing temperature and heating rate had a significant effect on the structural, optical and electrical properties of the studied thin films. The topography of SnO 2 thin films was examined by scanning electron microscopy (SEM). Furthermore, as-deposited films were characterized by X-ray diffraction (XRD), UV-Vis and impedance spectroscopy.

Section: Introductionmentioning

confidence: 99%

Electrical and optical properties of spin-coated SnO2 nanofilms

Waczyński

Materials Science-Poland

et al. 2014

Journal of Applied Physics

“…6 Hence, SnO 2 has gained attraction for applications in solar cells, heat mirrors, catalysis, and gas sensing applications. Recent experimental reports on transition metal (TM)-doped (V, 7 Cr, 8 Mn, 9 Fe, 10 Co, 11 Ni, 12 Cu, 13 and Zn 14 ) SnO 2 have shown promising application on the high temperature ferromagnetic semiconductors. Theoretical and computational studies on the TM-doped (Co, 15 Mn, 16 Ni, 17 Cu, 18 and Zn 19,20 ) SnO 2 have also been performed to understand the induced magnetism.…”

mentioning

confidence: 99%

Magnetism of Zn-doped SnO2: Role of surfaces

Pushpa

Ramanujam

2014

Surface effects on the magnetization of Zn-doped SnO2 are investigated using first principles method. Magnetic behavior of Zn-doped bulk and highest and lowest energy surfaces—(001) and (110), respectively, are investigated in presence and absence of other intrinsic defects. The Zn-doped (110) and (001) surfaces of SnO2 show appreciable increase in the magnetic moment (MM) compared to Zn-doped bulk SnO2. Formation energies of Zn defects on both the surfaces are found to be lower than those in bulk SnO2. Zn doping favors the formation of oxygen vacancies. The density of states analysis on the Zn-doped (110) surface reveals that the spin polarization of the host band occurs primarily from p-orbitals of bridging oxygen atoms and the Zn atom itself contributes minimally. The present work provides a key understanding on the role played by the surfaces in inducing the magnetism of doped nanoparticles and thin films.

Applied Physics Letters

“…Among these high T C compounds, a promising but less studied material is TM doped-SnO 2 , which evoked a lot of attention when S. B. Ogale et al 4 found a giant magnetic moment ͑GMM͒ in Co-doped SnO 2 . Following this discovery, TM doped-SnO 2 has been extensively studied experimentally [5][6][7] and theoretically. [8][9][10][11] Very recently, 12 we investigated the origin of GMM in doped SnO 2 .…”

mentioning

confidence: 99%

Surface-induced magnetism in C-doped SnO2

Rahman

García‐Suárez

2010

The magnetism of C-doped SnO2 (001) surfaces is studied using first-principles calculations. It is found that carbon does not induce magnetism in bulk SnO2 when located at the oxygen site, but shows a large magnetic moment at the SnO2 (001) surface. The magnetic moment is mainly contributed by the carbon atoms due to empty minority spins of p orbitals and is localized at the surface and subsurface atoms. No magnetism is observed when the carbon atom is located at the subsurface oxygen sites. The origin of magnetism is discussed in the context of surface bonding.