We prepared Co-doped ZnO films by the electrochemical deposition. X-ray diffraction (XRD), high resolution transmission microscopy (HRTEM), x-ray photoelectron spectroscopy (XPS), atomic force microscope (AFM), x-ray absorption near-edge structure (XANES), vibrating sample magnetometer (VSM), optical absorption, and photoluminescence (PL) measurements were carried out on the samples. The results showed Co atoms substituted Zn atoms in the ZnO lattice without the formation of the impurity phase. VSM measurements showed the ferromagnetic properties for the Co-doped ZnO samples. When the Co doping concentration increased, the band gaps were widened and the PL peak positions shifted towards the short wavelength direction.
This work demonstrats a convenient and effective approach to synthesize WSe 2 nanorods at only 600 °C in argon atmosphere after ball milling. The friction and wear properties of WSe 2 nanorods as additives in two kinds of base oil, GyT130 oil and 60N oil were systematically investigated. Compared to base oil, the friction coefficient of the base oil containing WSe 2 nanorods was obviously reduced and the wear behaviour was improved. The nanorods in the 60N base oil showed better tribological properties than that in the GYT130 oil. The friction-and-wear mechanism of the WSe 2 nanorods as lubrication additive was discussed.
Mn-doped ZnO were synthesized by solid state reaction and sol-gel method respectively. It was found that samples synthesized by solid state reaction containing Mn 2 O 3 and MnO 2 are a mixture of ferromagnetic and paramagnetic phases. Contrary, samples without second phases were found to be paramagnetic at room temperature. According to previous report, interface effects between Zn-rich Mn 2 O 3 and MnO 2 interfaces may be the origin of the ferromagnetic behavior observed in our samples prepared by solid reaction, so the alloy of Zn 1−x Mn x O may be paramagnetic at room temperature. Prepared by sol-gel technique, the samples without second phases in the XRD patterns are also room-temperature paramagnetic. Therefore we believe that the magnetism of Zn 1−x Mn x O is paramagnetic at room temperature.
The magnetic NiO/Fe19Ni81 nanostructure bilayer is deposited onto the colloidal spheres grown on a Si wafer by the self-assembly technology. The nanocap and the nanodot arrays form on the spherical surface and the Si substrate, respectively, which are confirmed by scanning electron microscopy and transmission electron microscopy measurements. Compared to the flat bilayer with the same composition deposited on the Si substrate, the exchange bias field HE from the nanocap is twice as large. The enhancement of HE in the nanocap is ascribed to the decreased thickness of the ferromagnetic layer induced by the sphere surface. The size and space of the biased caps are estimated based on the thickness variations induced by the sphere surfaces.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.