CuS and Cu1.8S have been investigated respectively as anodes of lithium-ion batteries because of their abundant resources, no environment pollution, good electrical conductivity, and a stable discharge voltage plateau. In this work, CuS/Cu1.8S nanocomposites were firstly prepared simultaneously by the one-pot synthesis method at a relatively higher reaction temperature 200 °C. The CuS/Cu1.8S nanocomposites anodes exhibited a high initial discharge capacity, an excellent reversible rate capability, and remarkable cycle stability at a high current density, which could be due to the nano-size of the CuS/Cu1.8S nanocomposites and the assistance of Cu1.8S. The high electrochemical performance of the CuS/Cu1.8S nanocomposites indicated that the CuxS nanomaterials will be a potential lithium-ion battery anode.

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Due to the high theoretical capability, copper-based oxides were widely investigated. A facile water bath method was used to synthesis CuO nanowires and CuO/Cu2O/Cu nanocomposites. Owing to the synergetic effect, the CuO/Cu2O/Cu nanocomposites exhibit superior electrochemical performance compared to the CuO nanowires. The initial discharge and charge capacities are 2,660.4 mAh/g and 2,107.8 mAh/g, and the reversible capacity is 1,265.7 mAh/g after 200 cycles at 200 mA/g. Moreover, the reversible capacity is 1,180 mAh/g at 800 mA/g and 1,750 mAh/g when back to 100 mA/g, indicating the excellent rate capability. The CuO/Cu2O/Cu nanocomposites also exhibit relatively high electric conductivity and lithium-ion diffusion coefficient, especially after cycling. For the energy storage mechanism, the capacitive controlled mechanism is predominance at the high scan rates, which is consistent with the excellent rate capability. The outstanding electrochemical performance of the CuO/Cu2O/Cu nanocomposites indicates the potential application of copper-based oxides nanomaterials in future lithium-ion batteries.

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The spin-torque induced magnetization precession dynamics are studied in a spin-valve with a tilted spin polarizer. Macrospin simulations demonstrate that the frequency of precession state depends both on the external DC current and the intrinsic parameters of devices such as the tilted angle of spin polarizer, the damping factor and saturation magnetization of the free layer. The dependence role of those parameters is characterized by phase diagrams. An analytical model is presented, which can successfully interpret the features of precession frequency.

Homogeneous amorphous MnxGe1−x:H films were synthesized under thermal nonequilibrium condition by magnetron co-sputtering technology with hydrogen in Ar atmosphere. Compared to the MnxGe1−x films without hydrogen, the MnxGe1−x:H films with hydrogen show higher concentration of hole carriers, larger conductivity, and higher saturation magnetization. Moreover, it was found that the anomalous Hall resistivity is proportional to the perpendicular magnetization. These electrical and magnetic properties indicate that the ferromagnetism of the MnxGe1−x:H films is intrinsic ferromagnetism mediated by the spin-polarized hole carriers.

Co2MnSi thin films are made by magnetron sputtering onto MgO (001) substrates. The crystalline quality is improved by increasing depositing temperature and/or annealing temperature. The sample deposited at 550 ∘ C and subsequently annealed at 550 ∘ C (sample I) exhibits a pseudo-epitaxial growth with partially ordered 𝐿21 phase. Sample I shows a four-fold magnetic anisotropy, in addition to a relatively weak uniaxial anisotropy. The Gilbert damping factor of sample I is smaller than 0.001, much smaller than reported ones. The possible reasons responsible for the small Gilbert damping factor are discussed, including weak spin-orbit coupling, small density of states at Fermi level, and so on.

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